ROOFS AND ROOFS OF MULTI-STOREY RESIDENTIAL BUILDINGS.
- Roof classification, requirements for them.
- Construction of prefabricated reinforced concrete roofs.
- Exploited roofs, their design.
- Roofing of multi-storey buildings.
In modern capital housing and civil construction, low-slope attic roofs with an internal drain, load-bearing and enclosing structures made of reinforced concrete are mainly used.
The structural element enclosing the building from above is called the roof. Their main types are attic, non-attic, operated roofs, large-span flat and spatial coatings.
Based on the main purpose of roofs - to protect the building from precipitation in the form of rain and snow, as well as from heat loss in winter and overheating in summer, it consists of load-bearing structures that perceive the transmitted loads from overlying elements. cops, and the enclosing part.
The following basic requirements are imposed on roofs. The roof structure must provide for the perception of a constant load (from its own weight), as well as temporary loads (from snow, wind and coatings that arise during the operation of the coating). The enclosing part of the roof (roof), which serves to remove precipitation, must be waterproof, moisture resistant, resistant to aggressive chemicals contained in the atmospheric air and falling in the form of precipitation on the coating, solar radiation and frost, not exposed to warping, cracking and melting. Coating structures must have a degree of durability consistent with the standards and class of the building.
Important requirements for roofs are the cost-effectiveness of their installation and ensuring the expenditure of minimum funds for their operation. Of particular importance is the use of industrial methods in the installation of coatings, which reduces labor costs at the construction site and improves the quality of construction and installation works.
To ensure the removal of precipitation, the coatings are arranged with a slope. The slope depends on the material of the roof, as well as the climatic conditions of the construction area. So, in areas with heavy snowfalls, the slope is determined by the conditions of snow deposition and snow removal; in areas with heavy rains, the slope of the roof should ensure rapid drainage of water; in the southern regions, the slope of the coating, as well as the choice of roofing material, are determined taking into account solar radiation.
Reinforced concrete prefabricated roof structures design with a slope of up to 5%. Three types of roof structures are used: attic, non-attic and exploited.
attic roof - the main option for covering in residential buildings of mass construction with an increased number of storeys.
roofless roof - the main type of coverage in low-rise mass public buildings. A non-attic roof is also used in residential buildings up to four floors high during construction in a temperate climate, as well as on areas of multi-storey buildings that are limited in area: above the engine rooms of elevators, above loggias and bay windows, attached shops, lobbies, vestibules, etc. In turn, attic roofs are also used in multi-storey public buildings, when their planning parameters coincide with the parameters of residential buildings, which makes it possible to use the corresponding prefabricated roof products.
exploited roof it is arranged both over attic and non-attic coverings. It can be arranged over the entire building or part of it and used for recreational purposes, both for the population (or employees) in the building, or independently, for example, for setting up an outdoor cafe.
The final choice of a roof drainage system during design is carried out depending on the purpose of the object, its number of storeys and placement in the building. In residential buildings of medium and high-rise buildings, an internal drainage system is accepted, in low-rise buildings - an external organized one, and in low-rise buildings located inside a block - an external unorganized one.
With internal drainage in residential buildings, one water intake funnel per planning section, but at least two per building, is provided. With an external organized drain, the distance between the drainpipes along the facade should be no more than 20 m, and their cross section should be at least 1.5 cm 2 per 1 m 2 of the roof area.
waterproofing reinforced concrete roofs are designed depending on the type of roof. For non-attic roofs (with the exception of roofs of a separate structure), multi-layer waterproofing roll coatings are used. Waterproofing of attic and separate non-attic roofs is carried out in one of the following three ways.
The first (traditional) is the installation of a multi-layer rolled carpet, the second is painting with waterproofing mastics (for example, organosilicon), which, together with the waterproof concrete of the roof panel, provide the protective functions of the coating, the third is the use of prestressed roof panels molded from high-grade concrete for strength and grades for water resistance, providing waterproofing of the roof. This version of waterproofing is experimental.
According to the adopted method of waterproofing, the requirements for the physical and technical characteristics of concrete for roofing panels change (Table 1).
Table 1. Minimum allowable values for concrete properties of roof panels
According to the method of removing air from the exhaust ventilation system through the roof structure, roofs with a cold, warm and open attic are distinguished. For each of these structures, any of the above hydro-isolation methods can be applied.
Attic roof structures are used in construction in the following six main options (Fig. 1):
A - with a cold attic and a rolled roof;
B - the same, with a rollless roof;
B - with a warm attic and a rolled roof;
G - the same, with a rollless roof;
D - with an open attic and a rolled roof;
E - the same, with rollless.
Bare roof structures are used in construction in the following five options (Fig. 2):
Zh - separate (with a roofing panel, attic floor, insulation and ventilated space) with a roll-free coating;
And - the same, with a rolled coating;
K - combined single-layer panel structure;
L - combined three-layer panel construction;
M - combined multilayer building production.
When designing, the type of coating structure is chosen in accordance with the purpose of the building, its number of storeys and the climatic conditions of the construction area according to the recommendations of Table. 2.
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Table 2. Structures of reinforced concrete roofs and their slopes depending on the type of building and climatic conditions of the construction area
Rice. 1. Schemes of structures of attic roofs: A, B - with a cold attic with a rolled (A) and non-rolled (B) roof; C, D - with a warm attic with a rolled (B) and non-rolled (G) roof; D, E - with an open attic with a rolled (D) and non-rolled (E) roof;
1 - supporting element; 2 - attic floor slab; 3 - insulation; 4 - non-insulated roofing slab; 5 - roll carpet; 6 - drainage tray; 7 - support frame; 8 - protective layer; 9 - vapor barrier layer; 10 - a strip of roofing material; 11 - supporting element of the frieze panel; 12 - roofing plate of a rollless roof; 13 - waterproofing layer of mastic or paint compositions; 14 - U-shaped plate - flashing; 15 - drain funnel; 16 - ventilation unit (mine); 17 - head of the ventilation unit; 18 - lightweight concrete single-layer roofing slab; 19 - machine compartment of the elevator; 20 - lightweight concrete tray slab; 21 - two-layer roofing plate; 22 - non-insulated frieze panel; 23 - insulated frieze panel
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Rice. 2. Schematic diagrams of the structures of non-attic reinforced concrete roofs:
Zh - a separate design with a rolled roof;
And - a separate design (with a roll-free roof);
K - combined panel single-layer construction;
L - the same, three-layer;
M - the same, building construction;
1 - attic floor panel;
2 - insulation; 3 - frieze panel;
4 - roofing panel of a rollless roof;
5 - supporting element; 6 - single-layer lightweight concrete roofing panel;
7 - roll carpet; 8 - three-layer roofing panel; 9 - cement screed;
10 - layer ceram-site slope;
11 - a layer of laying roofing material on mastic.
Attic roofs are made up of roofing panels (roofing panels and trays, attic flooring, supporting structures for trays and roofing panels, external frieze elements. The height of the through passage in the attic space should be at least 1.6 m. Local reductions of up to 1.2 m are allowed outside the through passage.
attic roofs with a cold and open attic (structure types A, B, D, E) contain an insulated attic coating, non-insulated thin-walled ribbed reinforced concrete roofing, tray and frieze panels, in which holes are provided for ventilation of the attic space. The area of ventilation openings on each longitudinal side of the facade is assigned in climatic regions I and II at 1/500 of the attic area, in regions III and IV - at 1/50.
The dimensions of the supply and exhaust openings in the frieze panels of open attics are taken to be significantly larger according to the results of thermal engineering calculations, according to winter and summer operating conditions.
Ventilation ducts cross roofs with a cold attic, which should be taken into account when laying out attic floor panels and roofing.
Roof structures with a warm attic (types C and D) are made up of insulated roof, tray and frieze panels, non-insulated attic floor and supporting structures of roof and tray panels. Since the warm attic serves as an air-collecting chamber of the building's exhaust ventilation system, the ventilation blocks of the lower floors are completed in the attic space with a 0.6 m high head without crossing the roof. Fascia panels are designed deaf (without ventilation holes). These panels in some areas can be solved translucent (for natural lighting of the attic), but not hinged. In the central zone of the warm attic, a common exhaust shaft is arranged (one per planning section) 4.5 m high from the upper plane of the attic floor.
Roof structures with an open attic (types D and E) are similar in composition of structural elements to structures with a cold attic, but the ventilation structures do not cross it, breaking off at a height of 0.6 m from the surface of the attic floor, as in roofs with a warm attic .
Exhaust air removal along with a common shaft is facilitated by intensive horizontal ventilation through enlarged ventilation openings in the frieze panels.
Roofs with inclined frieze panels and gable-shaped vertical frieze panels, echoing the traditional forms of mansard roofs, became a peculiar architectural variant of the structures of reinforced concrete attic roofs of multi-storey buildings. This option can be applied to both cold and warm attic roofs (Fig. 10.3). The facade finishing layer of steeply sloped frieze panels can be similar to that used for external walls ( decorative concrete or facing tiles) or made of roofing materials - clay, cement or metal tiles.
The design of a separate non-attic roof (type I) contains the same structural elements as an attic roof with a cold attic, but due to the fact that its airspace has a low height (up to 0.6 m), the solution of supporting structures simplified.
The roof panels of rollless roofs with a cold and open attic, as well as separate non-attic roofs, are solved in the same way. These are thin-walled (slab thickness 40 mm) ribbed reinforced concrete slabs. The butt edges of the panels and their junctions to the vertical structures crossing the roof (elevator shafts, ventilation units, etc.) are equipped with ribs 100 mm high. The joints are protected by flashings (or overlapped) and sealed.
Drainage trough-shaped trays are made of waterproof concrete with a bottom thickness of 80 mm and a rib height of 350 mm, a width of at least 900 mm.
Roof panels and roof trays with a warm attic are designed with two or three layers. The top layer is made of frost-resistant concrete with a thickness of at least 40 mm. For the insulating layer of two-layer panels, lightweight concretes with a density of 800-1200 kg / m 3 of class B 3.5-B7.5 are used, for three-layer panels - effective heaters with a density of less than 300 kg / m 3.
With rollless roofs, insulated roof panels have longitudinal edge ribs for overlapping or flashing mates.
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Rice. 3. Attic reinforced concrete roofs:
A - diagrams of a cross-section of roofs with a warm attic with a vertical frieze (a); with a steep frieze (b); B - details of the inclined frieze device; c, d - with a cold attic; d - the same, with heat; 1 - cold frieze panel; 2 - the same, roofing; 3 - jelly concrete beam; 4 - jelly concrete frame; 5 - insulated frieze panel; 6 - the same, roofing; 7 - supporting structure of the frieze panel
Rice. 4. Attic roof construction with a cold attic and a roof made of rolled materials (type A):
A - scheme-plan of the roof; 1 - ventilation unit; 2 - drain funnel; 3 - attic floor panel; 4 - frieze panel; 5 - supporting element of the frieze panel; 6 - insulation; 7 - support frame; 8 - tray panel; 9 - ribbed reinforced concrete roofing panel; 10 - main roof; 11 - additional layers of roofing material on bituminous mastic; 12 - protective apron made of galvanized roofing steel; 13 - mineral wool mats
Fig.5. Knots 2-4 mates of roll roof structures with a cold attic (type A):
A - an option for solving a cornice assembly with a lattice fence; B - the same, with a parapet; 1 - frieze panel; 2 cement-sand mortar; 3 - anchor release; 4 - roofing crutches after 600 mm are shot with dowels; 5 - galvanized roofing steel; 6 - fence post; 7 - additional two layers of roofing material on bituminous mastic; 8 - main roof; 9 - ribbed reinforced concrete roofing panel; 10 - concrete side stone; 11 - protective apron made of galvanized roofing steel; 12 - sliding strip of rolled material; 13 - mineral wool mats; 14 - a strip of rolled material with one-sided gluing to a width of 50 mm; 15 - support frame; 16 - embedded part; 17 - mounting connecting element; 18 - tray panel; 19 - drain funnel; 20 - filling with sealing mastic; 21 - drain pipe of the drain funnel
Atticless combined roofs a single-layer structure is designed as a panel of lightweight concrete or autoclaved cellular concrete (type K construction). Lightweight concrete roofing panels with a density of up to 1200 kg / m 2, cellular concrete - 800 kg / m 2. The panels provide cylindrical ventilation ducts in the subroofing layer. The roof is a four-layer roll, and the first layer of waterproofing is carried out at the factory to avoid wetting the structure during transportation, storage and installation.
Three-layer panels of combined bare roofs (type L) are manufactured in a single technological cycle or are assembled at the factory from two thin-walled ribbed plates and insulation between them.
Combined building-made roofs (type M) are erected by successively laying a vapor barrier layer on the upper floor of the building, filling along the slope, a heat-insulating layer, a leveling screed and a multi-layer waterproofing rolled carpet. Design M is the most time-consuming and has the worst performance. Its use should be limited as far as possible.
Rice. 6. Rollless roof with a cold attic (type B):
A, B - cross-sectional diagrams of the attic with internal and external drainage; B - prefabricated element of the catchment tray; G - the same, roofing panels for roofs with internal; D - the same, with an external unorganized drainage system; 1 - frieze panel; 2 - supporting element of the frieze panel; 3 - lattice fence of the roof; 4 - frieze panel of the end wall; 5 - roofing panel; 6 - flashing; 7 - drainage tray; 8 - catchment funnel; 9 - support beam; 10 - attic floor; 11 - support column; 12 - supporting element of the tray; 13 - drain hole; 14 - mounting loops
When constructing a roof from a 3-, 4-layer carpet, a set of constructive measures is taken to increase its durability and reliability. Apply a dot (or strip) sticker of the lower layer and armored ruberoid- for the top layer. The dot sticker promotes uniform distribution of water vapor pressure under the carpet, eliminating the formation of blisters and tears; armoring the coating with light-colored gravel increases the light reflection of the roof, reduces its radiation overheating, which prevents aging and leakage of mastic.
The places where the roof mates with protruding vertical structures (parapets, etc.) are isolated by laying a carpet on these surfaces with the protection of its upper edge with water-removing metal or plastic aprons. The transition of the carpet to the vertical plane is designed smoothly with the installation of slopes at the base of the carpet from a monolithic screed or the installation of prefabricated bars of a trapezoidal section.
An additional insurance for the isolation of these places is the mandatory installation of two additional layers of roofing material in the places where the carpet passes to the vertical plane.
Rice. 7. Rollless roof with a cold attic and internal drainage (type B):
A - scheme-plan of the roof; 1 - roofing panel; 2 - drain funnel; 3 - ventilation unit; 4 - attic floor panel; 5 - supporting element of the frieze panel; 6 - tray panel; 7 - U-shaped plate - flashing; 8 - insulation; 9 - reinforced concrete support frame; 10 - cement-sand mortar; 11 - sealant; 12 - head of the ventilation unit
Rice. 8. Nodes of mates of a rollless roof with a cold attic (type B):
A - options for conjugating the roof with the end of the outer wall; B - options for longitudinal joints of roofing panels; B - design options for coupling ventilation shafts with a roof; 1 - outer wall panel; 2 - frieze panel of the end wall; 3 - parapet slab; 4 - apron made of galvanized steel; 5 - roofing panel; 6 - supporting element of the frieze panel; 7 - strip of roofing material; 8 - insulation; 9 - attic floor slab; Yu - L-shaped parapet element; I - ventilation shaft; 12 - flashing; 13 - sealant; 14 - cement mortar; 15 - drainage tray; 16 - supporting element of the tray
Rice. 9. Variants of junctions of roll-free roof structures with a cold attic (type B):
A, B - options for the design of the roof fencing; C, D, - options for the design of an expansion joint; 1 - roofing panel; 2 - anchor release; 3 - fence post; 4 - U-shaped plate - flashing; 5 - waterproofing with mastic or paint compositions; 6 - cement-sand mortar; 7 - frieze panel; 8 - sealant; 9 - roofing crutches with a step of 600 mm; 10 - galvanized roofing steel; 11 - protective apron made of galvanized steel;
12 - embedded part; 13 - steel connecting element; 14 - tray panel; 15 - drain funnel; 16 - sealing gasket made of porous rubber; 17 - clamping ho-mute of the funnel; 18 - pierced mineral wool mats; 19 - downpipe drain funnel; 20 - insulating bitumen-rubber suit; 21 - hairpin; 22 - metal washer; 23 - steel strip; 24 - compensator made of galvanized roofing steel; 25 - interior panels of the attic.
Rice. 10. Roll-up roof with a warm attic (type B):
A - scheme-plan of the roof, 2 - drain funnel; 3 - supporting element of the frieze panel; 4 - frieze panel; 5 - roofing panel; 6 - tray panel; 7 - support frame; 8 - ventilation pipe; 9 - insulating insert; 10 - main roof; 11 - sliding strip of rolled material; 12 - cement-sand mortar
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Rice. 10.11. Joint nodes of roll roof structures with a warm attic (consumer goods B):
A, B - options for the design of the roof fencing; 1 - frieze panel; 2 - warming insert; 3 - anchor release; 4 - roof crutches with a step of 600 mm; 5 - galvanized roofing steel; 6 - stop-ka fences; 7 - three additional layers of rube-roid; 8 - main roof; 9 - concrete side stone; 10 - cement-sand mortar; 11 - protective apron made of galvanized steel roofing; 12 - roofing panel; 13 - sliding strip of rolled material;
14 - support frame; 15 - tray panel; 16 - two additional layers of roofing from mastics reinforced with glass mesh or fiberglass; 17 - filling with bituminous mastic; 18 - a bowl of a drain funnel; 19 - jet straightener; 20 - sleeve made of asbestos-cement pipe d = 150 mm; 21 - rubber gasket; 22 - clamping clamp; 23 - downpipe drain funnel; 24 - filling with sealing mastic; 25 - ventilation shaft; 26 - tow soaked in hot bitumen to a depth of 50 mm; 27 - an umbrella made of galvanized roofing steel; 28 - steel pipe with a flange; 29 - attic floor slab
Rice. 12. Rollless roof with a warm attic (type D):
A - scheme-plan, roofs: 1 - two-layer warm non-rolled roofing panel; 2 - exhaust shaft; 3 - protective umbrella; 4 - two-layer tray panel; 5 - frieze panel; 6 - head of the ventilation shaft: 7 - supporting element of the tray panel; 8 - riser of the internal drain; 9 - drainage tray; 10 - three-layer roofing panel; 11 - the same, tray panel; 12 - attic floor panel; 13 - concrete flashing; 14 - sealing mastic; 15 - insulation; 16 - concrete key.
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Fig.13. Joint nodes of roll-top roof structures with a warm attic (type G):
1- frieze panel; 2 - gernite; 3 - sealing mastic; 4 - concrete parapet; 5 - insulation; 6 - three-layer roofing panel; 7 - cement-sand mortar; 8 - two-layer roofing panel; 9 - U-shaped concrete flashing; 10 - tray three-layer panel; 11 - tray double-layer panel
Rice. 14. Schemes of plans for non-attic roofs of types "I", "K", "M". Knots of a non-attic ventilated roof of type "I":
a - with internal drainage; b - the same, with an external drainage system; B - parapet nodes of the roof; node I-1a - adjoining the roof and ceiling to the outer load-bearing wall; I-1b - the same, to the outer curtain wall; I-2a - to the brickwork wall; I-2b - to the wall of large blocks; 1 - multi-hollow floor panel; 2 - a layer of cushioning roofing felt on bituminous mastic; 3 - slab insulation; 4 - lime-sand crust; 5 - ventilated air gap; 6 - roofing panel; 7 - three layers of laying roofing material; 8 - a layer of roofing roofing material;
9 - protective layer of fine gravel 20-25 mm; 10 - cement-sand mortar; And - the outer wall of brickwork; 12 - external non-bearing wall; 13 - ventilation air; 14 - concrete parapet slab; 15 - concrete side stone; 16 - two additional layers of roofing material; 17 - protective painting with a waterproofing composition; 18 - mineral wool felt; 19 - lifting loop, bent and welded to the embedded part of the parapet block; 20 - blocks of the outer load-bearing wall; 21 - roofing galvanized steel; 22 - ventilation air grille; 23 - activated wooden cork; 24 - anchor pipe fencing; 25 - fence post; 26 - antiseptic wooden lath 66x80 mm
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Rice. 15. Non-attic ventilated roof type "G":
Nodes I-3, I-4 and I-5: 1 - outer wall; 2 - cement-sand mortar; 3 - ventilation air grille; 4 - eaves plate; 5 - roofing crutch; 6 - roofing galvanized steel; 7 - two additional layers of roofing material; 8 - flat asbestos-cement slab; 9 - multi-hollow floor panel; 10 - layer of cushioning roofing material; 11 - slab insulation; 12 - lime-sand crust; 13 - ventilated air gap; 14 - roofing panel; 15 - three layers of cushioning roofing material;
16 - a layer of roofing roofing material; 17 - protective layer of gravel 20 - 25 mm; 18 - brick wall; 19 - mineral wool felt; 20 - apron made of galvanized steel roofing; 21 - antiseptic wooden cork; 22 - antiseptic wooden board with a section of 120x50 mm; 23 - upper compensator made of galvanized steel roofing; 24 - internal transverse walls; 25 - lower compensator made of galvanized steel roofing, adjusted with dowels through 300 mm; 26 - dowels; 27 - parapet slab; 28 - concrete side stone; 29 - protective painting with waterproofing compound
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Rice. 16. Non-attic roof made of light-weight concrete panels of type "K":
Nodes K-1, K-2, K-3, K-4 and K-5; 1 - lightweight concrete cover panel; 2 - outer wall; 3 - mineral wool felt; 4 - side concrete stone; 5 - three layers of cushioning roofing material; 6 - a layer of armored ruberoid; 7 - two additional layers of roofing material; 8 - parapet plate; 9 - protective layer of fine gravel 20-25 mm; 10 - apron made of galvanized steel roofing; 11 - upper compensator made of galvanized steel roofing; 12 - antiseptic wooden board; 13 - antiseptic wooden cork; 14 - brick wall; 15 - internal walls; 16 - lower compensator made of galvanized steel roofing; 17 - ventilation duct; 18 - roofing crutch; 19 - roofing galvanized steel.
Rice. 10.19. Non-attic non-ventilated roof type M:
nodes M-5a - M-8; 1 - brick wall; 2 - cement-sand mortar; 3 - multi-hollow reinforced concrete panel; 4 - a layer of cushioning roofing material on bituminous mastic; 5 - a layer of expanded clay crushed stone or slag to create a roof slope; 6 - slab insulation; 7 - cement-sand screed; 8 - three layers of cushioning roofing felt on bituminous mastic; 9 - layer of armored roofing material; 10 - protective layer of fine gravel 20-25 mm; 11 - mastic waterproofing carpet reinforced with fiberglass;
12 - three additional layers of roofing material; 13 - three additional mastic layers reinforced with two layers of fiberglass; 14 - apron made of galvanized steel roofing; 15 - antiseptic rail along the entire length; 16 - mineral wool felt; 17 - window sill; 18 - antiseptic wooden cork; 19 - mastic; 20 - compensator made of galvanized steel roofing; 21 - antiseptic wooden board 19x150 mm along the entire length; 22 - roofing galvanized steel; 23 - dowels.
In some cases (for example, if a metal tile system is being installed on top of an old soft tile), this is possible. However, it must be understood that a damaged base may begin to rot and, thereby, provoke the failure of a new layer. That is why we would not recommend laying new materials on top of old ones. It is better to remove the damaged building material and complete the required work, as required by the technology.
As practice shows, the vast majority of roofs in ordinary private houses are built in such a way that it is not necessary to dismantle the roof base to install an additional insulating layer. If we talk about multi-apartment buildings, then the situation is different: since in multi-storey buildings, built-up coatings are used, insulation becomes impossible.
If there is damage to individual structural elements, then only these parts can be replaced. In this case, the area of damage should not exceed 35%. For larger problems, it is worth making a complete replacement of the truss system.
Urgent repair is required in case of a serious violation of the tightness of the coating: it may be required when part of the roof is torn off, water flows during precipitation, peeling, tearing or swelling of the roofing material.
We provide the following warranty periods:
- soft roof: 5 years
- metal roofing: 3 years
- roll and bituminous coatings: 3 years
- polymer tile and seam covering: 6 years.
Any leak is a problem that requires careful and timely repair. First, it is important to correctly determine the cause of the leak. Secondly, with self-repair, there is a risk of damaging serviceable elements that are nearby. If you are not a roofing specialist, we recommend calling a master who will not only fix the problem, but also provide a guarantee for their services.
In order to accurately determine the cause of the appearance of water, an examination is necessary, which will be carried out by a specialist. You can independently determine what is the cause of the appearance of moisture by the following signs:
- in the event of a leak in the roof, water begins to drip in the warm season after rain, and in the cold season in sunny weather and sudden warming.
- with the accumulation of condensate, moisture appears constantly and practically does not depend on weather conditions.
Flat roofs are often used in the construction of modern high-rise buildings, administrative and industrial buildings, and in suburban construction. In the latter case, they are most popular when creating low-rise buildings or outbuildings.
Basic requirements for flat roofs
The increased strength of the roof is very important for regions with heavy snowfalls. During winter periods, it will have to withstand a significant load as a result of the formation of a thick layer of ice and snow. This indicator is very important in the case of creating an exploitable roof.
A flat roof must perform the functions of reliable protection against rain and melt water and have a sufficient slope so that precipitation does not linger on it.
The design should not deteriorate under the influence of severe frosts and the scorching rays of the sun, sudden temperature changes and strong hail.
It should perfectly cope with the heat-insulating function.
All materials used in the construction of the roof must be fire resistant.
Pros and cons of flat roofs
Pros:
- Flat structures have a much smaller area than pitched ones, which allows significant savings on materials and during construction and installation work.
- The smaller footprint helps to optimize costs.
- It is possible to cope with the construction of such roofs in a shorter time than with the installation of pitched ones, since all the required materials can be located in close proximity - literally at your feet.
- Due to the same feature, maintenance and repair work is simplified: their implementation on a flat horizontal surface is greatly simplified.
- On flat roofs, it is convenient to carry out installation and necessary maintenance work that requires the use of special equipment: solar panels, air conditioning systems, antennas, etc.
- When creating a flat design, you can get additional meters of usable area and use them as a recreation area, sports ground or arrange a flower garden, garden. Currently, it is possible to cover the roof with paving stones or paving slabs through the use of special technologies. A roof paved with high-quality tiles, combined with garden furniture, a green area, a gazebo, will be an ideal place for a family holiday.
Minuses:
- with heavy snowfalls, snow mass will accumulate on the surface, which, with the onset of melting, often leads to the formation of leaks;
- often there is a need for the use of drains;
- in the cold season there is a risk of freezing of the internal drain;
- the drainage system is often clogged;
- a mandatory requirement is the mechanical cleaning of the surface from the snow mass;
- need periodic monitoring of the state of the insulation to prevent its moisture;
- From time to time it is necessary to check the safety of the tightness of the coating.
Types of flat roofs
There are four main types of flat structures:
Exploited roofs
Their peculiarity is the need to create a rigid base - otherwise it will not be possible to maintain the integrity of the waterproofing layer. The base is a screed based on concrete or corrugated board, which is necessary to create a certain slope for water flow. The heat-insulating material used in the installation of the operated roof will be subjected to significant static and dynamic loads and must have a sufficient level of compressive strength. With a small stiffness of the insulation on top, a cement screed device will be required.
Unexploited roofs
When arranging this variety, there is no need to create a rigid base in order to lay the material for waterproofing. You don't need a hard core either. For further maintenance of the roof, bridges or ladders are arranged, the function of which is to evenly distribute the loads over the roof surface. The construction of unused flat roofs will cost much less, but they will not last as long as exploited ones.
traditional roofs
The structure of traditional types of roofs provides for the location of a layer of waterproofing material over heat-insulating. The basis for the roof is a reinforced concrete slab, and water is drained from the roof surface by creating an inclined screed of expanded clay concrete.
Inverted roofs
Roofs of the inversion type practically solved the problem of leaks - the main drawback of flat structures. In them, the thermal insulation is located above the waterproofing carpet, and not under it. This technique helps protect the layer of waterproofing material from the damaging effects of solar ultraviolet radiation, sharp temperature fluctuations, the freezing process and subsequent thawing.
Compared to other types of roofs, inversion is more durable.
In addition, it is distinguished by increased functionality: you can arrange a lawn on it, make tiled masonry. The optimal angle of inclination of such roofs is considered to be from 3 to 5 degrees.
Device Features
The main subtleties of the construction of flat roofs are as follows:
- Vapor barrier is arranged by means of a bitumen-polymer membrane reinforced with fiberglass. Another option is to lay a vapor barrier film over the screed.
- Along the edges of the roof, a layer of vapor barrier material is wound vertically so that its height is greater than the height of the insulation layer, after which the seams are sealed.
- Above the vapor barrier, insulation is laid (in the case of a traditional roof).
- A protective carpet is laid over the insulation, which is made of waterproofing materials with a bituminous base.
- If expanded clay is used as a heater, a cement screed must be made under it. Waterproofing is laid in two layers on it.
- When installing light structures for which significant loads are not provided, it is necessary to glue the waterproofing sheet along the entire roofing perimeter.
Mounting
A flat roof cannot be laid strictly horizontally - a minimum slope of at least 5 degrees must be observed. This requirement is due to the need to ensure the descent of rainwater and snow from the roofing surface. Another important point: it is necessary that the slope is created not only by the coating, but mainly due to the correct implementation of expanded clay or slag backfill. Even if the slope angle reaches 10 degrees, this will not interfere with the uniform laying of the heat-insulating material.
Lightweight flat roofs
In the construction of such roofs, the work is divided into several stages.
As a result of the work done, a warm and fairly reliable flat-type roof is obtained: in the context, it resembles a multilayer cake based on several components.
Hard roof device
When creating floors of this variety, expanded clay is best suited as a heat-insulating material. The minimum thickness of its layer should be 10 cm. Above the laid expanded clay, it is necessary to make a cement-sand screed with a thickness of 40 to 50 mm. To ensure greater strength, a reinforcing mesh is placed in its middle layer. Such a measure is necessary to maintain the integrity of the coating while people are on it during repairs, maintenance, etc. In addition, it is these roofs that are optimally suited as the basis for a pool or recreation area.
The manufacture of beams of such structures is most often carried out on the basis of a metal channel, since parts made of wood will not withstand significant loads.
Another requirement for the installation of operated roofs is the sufficient thickness and strength of the walls of the house.
Methods for arranging flat structures
There are several basic ways to create flat roofs:
- Through the installation of concrete floor slabs. Such work can be done in a fairly short time, but special lifting equipment is required. The use of this method involves the implementation of insulation. The material can be laid both inside and outside.
- Using metal channels or I-beams, on top of which it is necessary to lay boards: their thickness should be 25-40 mm. A layer of expanded clay is poured on top, then a concrete screed is created.
- The creation of the overlap is carried out by means of monolithic concreting. This requires a high-strength formwork with thick supports. The supports are fastened together with jumpers. This type of overlap also needs to be insulated.
- With the help of large ceramic blocks: they are laid on top of metal beams. Such blocks replace wooden flooring. The main advantage of this method is the use of ceramics, which are characterized by increased mechanical strength, resistance to moisture and excellent sound and heat insulating properties. Large-sized ceramic blocks do not need additional insulation: when using them, you can limit yourself to such a measure as creating a concrete screed.
FINDINGS:
- Flat roofs are often used in the construction of modern high-rise buildings, administrative and industrial buildings, and in suburban construction.
- Flat structures must have increased strength - especially when a large amount of precipitation falls.
- Flat roofs have a much smaller area than pitched ones, which allows significant savings on materials and during construction and installation work.
- The main disadvantage of such roofs is that during heavy snowfalls, snow mass accumulates on the surface, often leading to the formation of leaks.
- Flat roofs can be exploited, non-exploited, traditional and inversion.
- Roofs of the inversion type practically solved the problem of leaks - the main drawback of flat structures.
- A flat roof cannot be arranged strictly horizontally - a minimum slope of at least 5 degrees must be observed for atmospheric precipitation to drain.
- Lightweight flat roofing is fundamentally different from hard roofing.
- Flat roofs can be created in several ways.
In the video you can see how to drain a flat roof using a non-combustible Rockwool insulation system.
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Perhaps, many residents of apartment buildings faced such a problem as leakage, as well as an insufficiently reliable condition of the roof. In one row here are such disadvantages as poor-quality coating, roof collapse in an old house, etc. That is why the overhaul of the roof of an apartment building is one of the most pressing issues for many residents.
Very often, many citizens, seeking help from various authorities involved in house maintenance, are faced with their complete inaction, as a result of which the collection of funds for roof repairs in an apartment building is carried out independently.
However, before contacting such bodies and paying for the services of roofing specialists, it is necessary to understand the very reason. Next, we will talk about what types of roofs exist in apartment buildings, as well as the problems that arise in connection with them and ways to solve them.
Types of roofing in apartment buildings
Since there are several types of roofs in multi-storey buildings, it is important to understand the features of each of them, since repair work can vary greatly.
According to the design and shape of the roof are divided into:
- single-pitched (with a different inclined angle);
- gable;
- multi-slope;
- pitchless (standard flat roofs);
- complex (more typical for modern buildings than for old houses).
The roof structure includes an external covering and a support located from the inside (this can be a rafter system or a reinforced concrete slab). Also mandatory elements are the drainage system, as well as layers of insulation and waterproofing. One way or another, when performing a major overhaul of the roof of an apartment building, it is imperative to take into account all the design features of the roof.
Roof repair methods
Works on the restoration of the roofs of buildings with many apartments are usually divided into two large groups: current, or temporary, and capital, or complete.
Thus, the current repair of the roof of an apartment building is carried out if any defects in the roof system are found. Very often, all work comes down to replacing the old and damaged roofing, which is usually roofing material, with a new one, eliminating the cracks and crevices that have appeared. Based on the need, the new coating can be laid in one or two layers. Upon completion of the repair work, all seams and joints of the roof sheet are completely sealed with special substances.
Regarding finances, this type of repair is not too expensive, so it is more common. However, there is another type of current repair, when it is not necessary to lay a new roofing sheet. In the place of the defect, after a preliminary incision, the edges are bent, and the internal space is carefully cleaned. Then it is dried with the help and treated with a layer of building mastic, both the coating and its base. The edges are returned to their place, after which they must be pressed tightly against each other, waiting for complete adhesion.
Places with manifested rot are completely cut out, the roof is cleaned. All defective places are filled with the same mastic, and then a new piece is glued to the treated place close to the old material. Of course, this method of repair is far from the highest quality, but in our time it is quite common, especially on the roofs of old houses.
A major overhaul of the roof of an apartment building is a complete alteration of the roof. The old coating is removed from it, after which a fresh screed is poured and a new roofing carpet is laid in two layers. Such repairs should be entrusted only to specialists, since during the work the interior decoration of the apartments located on the upper floors may be damaged.
If the roof is leaking in an apartment building, then this may be the result of improperly performed work. The main work during the overhaul is to fuse the roofing material with a special gas burner (read: ""). The underside of the roofing carpet is heated from below, after which the material is gently pressed against the base of the roof. It is very important to control the temperature of the fire, as its incorrect value can lead to the destruction of the material. It is necessary to lay the coating according to the principle of overlap, and all seams must be treated with building sealant.
Factors causing roof leaks in apartment buildings
There is only one way to avoid leaks - by performing a major overhaul of the roof. The causes of these unpleasant defects can be very different, but most often they appear after heavy rains or during the period of mass melting of the snow cover.
So, the reasons for roof leaks in apartment buildings can be the following:
Roof leak detection
Before applying for a major repair, you need to clearly identify the place that is damaged. Most often, for this, the place of leakage is compared and already along it there is a source of damage on the roof. On soft bituminous roofs, this is very easy to do - air bubbles form at the site of the defect.
In this case, the carpet should be completely replaced, and the necessary place should be dried well. It is not worth doing this work on your own, it is better to entrust the work to specialists. But if there is a desire, detailed descriptions of the entire progress of work with videos and photos can always be found in our articles on roofs and their repair.
Sometimes it happens that the problem of leaks on pitched roofs can also be complicated by rotting wooden rafter legs. With this outcome, not only the roofing is usually replaced, but also individual structural elements.
Roofs according to the principle of fusing
As it has already become clear, the essence of the overhaul comes down to the installation of welded materials. According to existing standards, scheduled repairs with the replacement (if necessary) of individual sections of the coating should be carried out by special services twice a year.
The whole process consists in fusing roofing material and other overlapped materials with a gas burner. Such repairs should be carried out for flat roofs, which are the majority today (read: ""). Such material is resistant to moisture, temperature extremes, as well as direct ultraviolet rays.
What to do if the roof leaks, in detail on the video:
Pitched roof repair process
Pitched roofs are usually covered with a different material. Often these are sheets of metal treated with zinc or simply painted. Repair work in this case consists in finding damaged elements of the coating, replacing them competently and monitoring the condition of the roof base under the coating. To do this, the material must be removed and the necessary work carried out to restore the system of rafters and battens, as well as directly to the base located under the coating.
Sometimes it is impossible not to perform such an important part of the work as replacing the waterproofing layer and installing additional high-quality insulation. If the damage is minor, you can simply patch and seal all joints with sealant.
Any cracks and gaps should be filled with polyurethane-based sealant and covered with special polyurethane plasters. It is important that the damaged area to be repaired be degreased and treated with a primer before all work. After the completion of the restoration, it is customary to cover the roof with a paint specially designed for a particular roof, the functions of which are to give the coating greater strength and increase the service life.
When we talk about "types of roofs" and "types of roofs of houses", we do not always clearly understand the difference between these two concepts. Therefore, before talking about what roofs are, let's find out the differences in the concepts of "roof" and "roof".
The roof (in the traditional sense) is a part of the building structure, which provides protection from all types of precipitation, retains heat or protects against overheating. That is, this is the entire upper structure of the structure. For a modern stone building with a flat design, these are floor slabs, heat and waterproofing. Exit, fences, ventilation ducts and their protection, antenna attachment elements, funnels for storm drains are also roof elements. There is no consensus regarding the ownership of the hatch with a lock, which is hung by the ZhES so that they do not climb on the roof. For a house with an inclined (pitched) structure, this concept includes a supporting truss system or trusses, insulation, hydro and wind insulation, pipes, weather vanes and roofing.
In fact, from the point of view of Soviet building science, the roof is a pre-revolutionary and illiterate concept, and only the progressive term “covering” should be used. But in life, even professional designers and builders rarely use it. Perhaps due to the possibility of a dual interpretation. In part, the definition of “covering” has taken root in relation to structures with a supporting reinforced concrete or metal base, mainly flat ones. And to call the upper part of St. Basil's Cathedral or the roof of a village hut a “covering” would never occur to any architect, even though they were taught “correctly”.
The roof is only a shell that protects the coating from atmospheric influences. The roof does not perform load-bearing functions. That is, floor slabs, truss system, beams, insulation do not apply to the roof. Often, it includes a load-bearing roof preparation: lathing, flooring, screed. The material laid on the prepared surface: Soviet roofing material and slate, folk Russian-French ondulin, fabulous German tiles and New Russian copper are called roofing.
Flat and pitched designs
Roofs are flat and pitched. In accordance with SNiP, roofs with a slope of up to 12 ° are flat, with a large slope - pitched. On flat roofs, the slope is arranged to remove precipitation, 1.5-3 ° is enough.
The flat roof provides a lot of room for imagination in terms of design.
The pitched roof can be very original.
Attic and non-attic roofs
As the name implies, an attic roof has an attic, a non-attic one does not. The Russian hut, and indeed most types of traditional dwellings of all countries and peoples, have a ventilated attic. With the exception of mobile housing: yurts, tents, wigwams. It's hard to do there. Also, there are no attics among the tribes living in the equatorial jungle, they do not need them. Attics (technical floors) are in modern multi-storey residential buildings. Therefore, if the roof leaks, the tenants will not know about it immediately.
Atticless (synonymous - combined) coatings can be pitched (mansard) and flat. We are familiar with flat combined structures from panel "Khrushchev". The attic device allows you to use the attic as a full-fledged living space. Non-attic and mansard roofs require good thermal insulation of the upper floor. The roof of a one-story building can also be combined.
The combined gable roof in a one-story house creates the impression of spaciousness
Types of flat coverings
In terms of layout, flat roofs are quite similar, differing mainly in design. According to the mutual arrangement of the layers of insulation and waterproofing, in addition to the usual type, inversion roofs are also distinguished, in this case, a hygroscopic (waterproof) insulation is located above the waterproofing layer. As load-bearing structures in flat roofs, prefabricated or monolithic reinforced concrete, metal profiles with metal beams, wooden beams with solid flooring can be used.
The structure of the roof of a flat roof over a reinforced concrete slab is multi-layer
The area of flat roofs can be used by laying a covering that can be walked on: ceramic or paving slabs, boardwalk, or arranging a lawn on the roof.
In New York, a program has been adopted to turn the roofs of public buildings into gardens and lawns.
In fact, arranging a lawn on the roof of a house is not as difficult as you might think. Perhaps the only thing that is relatively expensive is a waterproofing polymer membrane. Everything else is quite simple, and grass care is standard: it needs to be mowed and watered in a drought. A layer of earth additionally protects the premises from cold in winter and from overheating in summer.
The design of the lawn on the roof is quite simple. It is necessary to use reliable waterproofing - a roofing polymer membrane
Pitched construction details
Before talking about what roof shapes are, let's define the main details of pitched roofs and terms. Main elements: ridge, inclined rib, valley (groove). Overhangs are divided into cornice (lower) and gable (end or gable). For most types of roofing, in addition to the base material, there are separate additional elements for protecting and decorating roof details.
The main elements of pitched roofs are standard.
Consider what are the roofs of houses, depending on the configuration. The forms of pitched roofs are very diverse. More often, the most simple in design and rational single-pitched, gable and hip types and roof structures are used.
The first eight types shown in the illustration are available to a private developer of average income. The rest are quite complex and expensive to implement.
Consider the individual types of roofs and their properties in more detail.
Shed cover
A roof with one slope is as simple as possible structurally, has a minimum number of parts. There is no ridge, for non-ventilated roofing (eg flexible tiles, seam roofing) there is no need for special ventilation elements. It is enough to provide a ventilation layer above the insulation, and ventilation holes can be placed in the filing. A shed roof does not have valleys, ribs and ridges, which are most exposed to atmospheric influences. The maximum wear of roofing in cold climates occurs in the valley, as snow and ice lie there longer. A simple roof with a slope in one direction is exposed to uniform rainfall, ultraviolet radiation and wind. The snow load is also distributed evenly. Ceteris paribus, a shed roof will last a little longer. And it will cost less: the truss system is simpler, the minimum number of not always cheap additional elements.
Russian project of a typical house with a shed roof. A high slope with living rooms should be oriented to the sunny side
Shed roofs are quite popular in developed countries. More often they are used for inexpensive, or, conversely, prestigious housing. For a house with an attic, one slope allows you to rationally organize the layout, bringing living quarters under a high slope, and stairs, bathrooms, and wardrobes under a low slope. In a premium-class home, such a roof makes it possible to create a magnificent interior.
For the construction of this country house, simple materials were used: wood, galvanized metal profiles and a lot of glass. Large roof overhangs protect the walls from precipitation, and the premises from overheating. Athermal stained glass windows fill the house with light, open up the landscape and protect people from the cold
The roof with one barrel-shaped slope looks quite interesting.
Gable design
The most common form in the world. A gable (gable) roof is traditional in almost all countries where at least some precipitation occurs. It is not much more difficult to build a supporting structure for two slopes than for one. It is very durable, especially if it is possible to build a closed truss system using a puff.
The tightening (2) tightens the rafter legs (1). From the closed triangular contour, only the vertical load is transferred to the Mauerlat (3) and the wall.
For large spans, additional supports must be used.
The gable roof is simple in execution, economical in materials, it is not difficult to build it yourself. Gables serve as a better place than slopes for placing windows; it is easy to equip an attic.
The gable roof fits perfectly into the design of the frame house, allows you to rationally use the space of the upper floor
The slopes do not have to have the same slope; the shape of the roof may be asymmetrical. The slope of the roof is determined mainly by the layout of the second floor.
The peaked roofs of the half-timbered houses traditionally concealed attics, where the inhabitants stored part of the supplies. In this reconstructed house, the attic is adapted for living quarters.
The Swiss chalet has a gable roof with a slight slope.
The minimal slope and open space of the upper floor create a wonderful, spacious interior.
A gable roof can have many options. With a house plan more complex than a simple rectangle, more complex roof shapes are inevitable.
Gable roof with additional gable. With a stretch, it can be called multi-forceps
A gable (as, indeed, a shed) roof is perfect for landscaping.
Green roof slope must not exceed 25°
hip view
A hipped or hipped roof is more complicated than a gable roof. Both the rafter system and the roofing will cost more. But you do not have to build masonry gables. With an inexpensive roofing (asbestos slate, ondulin), a hip roof, taking into account the absence of gables, will cost less than a gable roof. At more expensive - hardly. Of the positive properties of the hip structure, one can name the optimal aerodynamic resistance of such a structure, which in general can increase its service life (slightly). The slopes on all sides of the house allow you to make large canopies around the perimeter of the entire structure, providing the walls with the best protection from precipitation. But in the organization of the attic space, the hipped roof loses.
Simple four-pitched attic roof
There are varieties of hip roofs: semi-hip (an intermediate type of roof between a gable and hip), hip with a visor, or their varieties.
The main part of the roof of a rather complex shape is half-hip. On the right, a bay window with a multi-pitched roof is attached, a pediment is arranged.
The windows in the hip roof have to be built into the slopes, into the roofing. This complicates their construction and operation and often costs more than placing a window in a pediment.
Skylights of this type are called "bull's eye"
Multi-slope variety
A hipped roof is called a hipped roof. But if the house does not have four outer corners, but more, there will also be more slopes. A roof with more than four slopes is called a multi-pitched roof.
Multi-pitched roof is difficult to install
A hipped roof is called a hipped roof, all the faces (slopes) and edges of which converge at one upper point. Such a roof does not have a horizontal ridge.
Shed roof. Three types of skylights are placed on it at once
Mansard construction
Mansard roofs are called roofs of various shapes and types, which are united by one common feature: the shape of the slope is broken in order to increase the height of the attic rooms. Thus, it is possible to avoid the installation of sloping ceilings, to arrange full-fledged rooms at the top. The broken contour of the rafters can be used for any type of roof: gable, hip, semi-hip and so on.
The truss construction of a gable mansard roof was assembled.
The design of the mansard roof allows you to connect the upper and lower beams (puff), racks, rafters into a single truss, which provides it with extreme strength and allows you to somewhat reduce the cross section of the frame elements.
The load from the mansard roof truss is transferred vertically
Mounting the load-bearing structures of mansard roofs is more difficult than for prototypes with a straight slope. Slightly larger roof area. Accordingly, the cost is higher. However, these costs are paid off by increasing the area of \u200b\u200bnormal height on the attic floor.
Mansard roof based on a gable roof. Additional fractures in the eaves area allow creating large overhangs, making the roof vaguely reminiscent of Chinese pagodas
Pleasant to the eye hip mansard roof. Slopes divided into different volumes, the lower part has a curvilinear shape
Roofs of complex shape
All kinds of domed, conical and closed roofs are complex in execution and were invented by architects to decorate important public buildings. After the period of “crimson jackets” and “locks on the ruble”, complex roofs in the architecture of individual residential buildings are not common.
Residential building with a complex domed roof
Sometimes complex roofs are made up of known elements and are "hybrids" of different types.
This roof combines the features of a gable, hip, semi-hip, pyramidal and conical roofs.
But people tend to decorate their home, make it unusual. Sometimes there are "hybrid" types of roofs, which are difficult to unambiguously define.
The natural slate roof is definitely not flat. Germany
Simple in form, but unusual roof. To be more precise, this house has two of them, downstairs and upstairs.
The roof of this "dugout" would have been designed for sledding in winter, if palm trees were not reflected in the windows. And what type is it?
The choice of roofing material for a pitched roof
Types of roofing are determined by the material of the roofing. The roof can be tiled, metal, shingled, copper and so on. The choice of roofing is primarily determined by the financial capabilities of the developer, the aesthetic tastes of the spouse and himself, and secondly by the shape of the roof and its slope. Roofs of curved shapes are covered with small-piece or flexible coatings, sheet materials are more suitable for simple shed and gable roofs. In the presence of fractures (inclined ribs, valleys), cutting sheets is less rational.
The table shows the minimum roof slopes for different types of roofing.
For roofs of simple shapes, you can use any roofing material without restrictions. Roofs of complex curvilinear shape can only be decorated with small-piece (natural tiles, slate slate, shingles, shingles), flexible (bituminous tiles) coating. A roof made of galvanized steel, copper, steel with a titanium-zinc coating is also suitable, provided that the elements are individually cut and the fold is made on site.
So, we found out what types of roofs are. What to choose for yourself? First of all, the roof must fit the budget. The more complex the form, the more money you have to spend. Any builder will cope with a gable roof. In Germany, there are 80 percent of such roofs. And why are we worse? If you have the funds, you can think of something more original, but simple things can be done beautifully.