Many people are used to thinking that it is customary to build flat roofs only on multi-storey buildings and industrial buildings. However, recently this type of roofing has been increasingly used in the construction of private houses. A flat roof in a private house is built without difficulty, given modern technology and a variety of building materials.
There are 4 types of them:
- Exploited. The main feature of this type is a fairly powerful base, otherwise there is a possibility of damage to the waterproofing layer. Decking or concrete screed, acting as a base, allow you to create the necessary slope for arranging a drain. Thermal insulation on such a roof must be resistant to serious loads. All this is done in order to use the roof of the house in any capacity, whether it be a work site or a recreation area.
- Unexploited. Here, the rigidity of the base of the flat roof structure is not as important as in the above embodiment. And the strength of the insulation also does not play a significant role. This roof is cheaper than the exploited one, but it will also last a shorter period.
- Traditional. A feature of their device is the periodicity of the layers - waterproofing goes above thermal insulation. Here, there is a reinforced concrete slab at the base, and an inclined expanded clay concrete screed is used for the drain.
- Inversion. The device of a flat roof in this embodiment has practically no problems with water leaks. Here, the thermal insulation is above the waterproofing, which gives the latter protection from ultraviolet rays and the effects of temperature fluctuations. Such a roofing device turns out to be the most durable and functional, which opens up a lot of opportunities for using the roof space.
Important! Angles in the range of 3 to 5 degrees are considered optimal for the slope of the inversion type of a flat roof.
Advantages and disadvantages of this design
A flat roof in a private house, like other types of roofs, has a number of pros and cons. It is worth considering the advantages that determine its popularity in modern construction:
- Smaller area than other types of roofing - and this saves effort and money;
- Convenience and safety of work - it is quite difficult to fall from a straight horizontal surface, and all the necessary tools are at hand;
- Rapid construction - as a consequence of the first two advantages, such work is done much faster;
- Ease of maintenance and replacement of roofing - the dismantling of worn parts is usually not carried out, but a new cake is laid directly on the old one;
- The use of additional territory - the arrangement of an exploited roof opens up great prospects;
- It is possible to install transparent roof elements - the view of the open sky on the ceiling is extremely tempting for many;
- Giving your home clear geometric shapes - if the drawing of the house allows, then you can give it a unique look with the help of such a design, especially considering that minimalism is now extremely popular.
It is also worth mentioning the disadvantages of this design:
- Snow and leaves accumulate periodically - sometimes mechanical cleaning of the roof is required;
- A more complex structure - the presence of gutters suggests their inevitable blockages, especially in bad weather;
- Regular control - the humidity of the insulation and the general condition of the roof must be constantly checked;
Not surprisingly, some people may have doubts about the reliability of this type of structure. But judging by the experience of the owners of private houses with a similar roof both in Russia and abroad, this type of roof functions successfully and pleases its owners.
Do-it-yourself flat roof installation
Now on the Internet you can find a lot of photos of houses with flat roofs of a wide variety of designs. Interested in the question of how to make a flat roof with your own hands? Before you build a roof, you must first familiarize yourself with the drawing of the house and make sure of its technical characteristics.
The design features of a flat roof depend on many factors. If this is an unheated room and the roof is being built with your own hands, then it is enough to install support beams, on which the base is then laid from uncut boards fastened with screws or nails. When installing a flat roof on a garage, roofing material often acts as a waterproofing due to its cheapness. Strips of roofing material are applied in the direction of the slope of the roof, fixing them with wooden or steel slats. A do-it-yourself flat roof for an unheated room is created quite easily - here all the work can be done by one person without anyone's help.
When installing a flat roof on a private house that is planned to be heated, the following procedure is usual:
- Installation of floor beams. Strict observance of the horizontal is required. Here and in subsequent stages, the participation of several workers will be required.
- Flooring installation. Usually an uncut board with a thickness of no more than 5 cm is taken.
Important! The size of the lumber section increases in proportion to the distance between the support beams.
- Waterproofing installation.
- Thermal insulation laying. In this case, the filling insulation is reinforced with a concrete screed, which dries for a couple of days.
- After the screed dries, a bitumen-based primer is applied to it, then roofing material is laid and glued.
The structure of the roofing pie
In order to make the roof reliably protected from moisture, it is necessary to place materials in layers one above the other - this arrangement is extremely important. The standard base is made of concrete slabs or profiled metal. It is able to support the weight of the entire structure above, transferring it to the load-bearing partitions, which, in turn, transfer it to the foundation of the house.
Important! The operated roof should have the most solid foundation.
Then come the standard layers: vapor barrier, thermal insulation and waterproofing. When choosing a flat roof, you should be guided by the preferences of the owner and the capabilities of the building itself. From a huge cottage to a small cozy house built many years ago, flat-roofed houses will be reliably protected from various environmental influences for many years to come.
A still unusual decoration of country cottages is a flat roof. It is believed that flat roofs are intended only for urban development or for industrial buildings. But it's not. The roofs of houses in historic neighborhoods are often pitched. And at a private house you can make a flat roof.
Now we will look at what it is, what are the advantages / disadvantages and how to make a flat roof with your own hands.
Types of flat roof
Structurally, flat roofs are divided into two main types: on beams and those with a concrete slab at the base.
Flat roofs are never completely flat, there is still a small angle (within a few degrees). This is necessary for the flow of water. Otherwise, it will stagnate on the roof.
Most often, internal drains are arranged on flat roofs: funnels are mounted in the roof, risers from them pass through the interior. Funnels are placed on the lower part of the roof, at the rate of one riser per 150-200 squares.
The waterproofing around the funnels is reinforced, cable heating is also recommended (so that the water in the riser does not freeze). If the flat roof is without a parapet, and the angle is decent (from 6 degrees), the drainage system can be standard external, as for pitched roofs: gutter and pipes.
Roofs are subdivided according to functionality, the device of the roofing pie and the type of coating. Here are some of the main varieties:
- The unexploited roof is flat. It is built solely for the sake of originality and economy of material. It does not need to strengthen the structure.
- Operating flat roof. It can be used for any purpose, from the placement of an outdoor pool and ending with a parking lot.
The type of overlap depends on the intended purpose: it is obvious that with high expected loads, the base should be a concrete slab. But this does not mean that the entire building should be brick or concrete. For example, a flat roof in a wooden house can also be exploited. Of course, it cannot be used as a heliport, but it is quite possible to arrange a solarium, set up a garden or put up a gazebo for tea drinking. Of course, a sparse crate cannot be made, only a solid one.
- traditional roofing. The classic version of the roofing cake: a waterproofing layer on top of the insulation, the base is concrete, for the outflow of water - expanded clay concrete (sloping screed).
- Inversion roof. Here, the insulation lies on top of the waterproofing and protects it from damage. The floor can be finished with paving or ceramic tiles, you can also plant a lawn here. A mandatory requirement for an inversion design is an angle of 3-5 degrees.
Roofs are attic and non-attic. Both types have their advantages: the presence of an attic allows you to place all the necessary communications on it (ventilation pipes, an expansion tank for heating, etc.), a barren roof can be made exploitable.
One of the options for a non-attic design is a flat combined roof: the attic floor is combined with the roof, the lower side is the ceiling in the living room.
note
According to the device, these roofs differ from simple non-attic ones; it is impossible to make them exploitable.With a house height of ten meters or more, as well as on exploited roofs, a parapet must be installed without fail. For exploited - not less than 1.2 meters.
If the roof is not in use, and the cottage is low, you can make a flat roof without a parapet or install fencing bars instead, or even do without them.
General arrangement of a flat roof
It is obvious that the devices used for roofs for various purposes will differ:
The most common coating is flat roofing. This is cheapness, simplicity and high laying speed, excellent waterproofing. The cheapest material that can be used to cover a flat roof is roofing material.
The disadvantages of rolled materials (and roofing material in particular) are low durability, low mechanical strength. For exploited roofs "with high traffic" tiles are preferable.
A flat roof made of corrugated board and a flat roof made of corrugated board can only be made in a non-exploited version and with the necessary slope. When choosing a material, you need to read the instructions for the model: some types of profiled sheets and metal tiles can be laid on roofs with a slope of less than 11 degrees.
Some brands of corrugated board can also be used as a base for an unexploited roof, instead of plywood or concrete slab.
There are other coating materials for unused roofs:
- Polycarbonate;
Pros and cons of flat roofs
Advantages:
- Original look. Flat roofs in cottages are rare.
- Possibility of exploitation.
- Flat roof - easy installation and savings on materials. But it depends on how you plan to operate the roof. And that construction will cost even more than an expensive pitched roof made of ceramic tiles.
- Laying, maintenance, repair on a flat roof is easier than on a slope.
- Flat roofs are windproof, pitched roofs have windage.
Minuses:
- A flat roof leaks more often than a pitched one. It is necessary to constantly monitor the condition of the waterproofing layer.
- The need to clear the roof of snow.
- Flat rolled roofing requires more frequent repairs and resurfacing than metal profiled, tiled and other pitched roofs.
So which roof is better, flat or pitched? Exclusively a matter of taste.
Building a flat roof
Consider the option when the profiled sheet is used as the basis of the roof:
1. Sheets are laid on the beams (rafters). The step between the rafters depends on the profile. For example, for load-bearing profiles with a corrugation height of 6-7.5 centimeters (H60, H75), the step between the beams is 3-4 meters.
2. Laying a vapor barrier film. The film is laid with an overlap, the joints must be sealed with mounting tape.
3. Thermal insulation. Mineral wool boards are usually used for this purpose. Please note that the corrugation depressions also need to be filled with insulation.
4. Waterproofing. For this purpose, a polymer film is suitable. If the insulation is mineral wool, you can also use built-up waterproofing, because. cotton wool is a non-combustible material.
5. Finishing coat. You can also use fused. A roll is slowly rolled out over the roof, heating it with a burner along its entire length. The deposited coating is pressed against the roof and smoothed out.
6. On flat roofs it is possible to lay the built-up roof in several layers.
In other cases, a flat roof on wooden beams is arranged more traditionally: a solid sheathing of plywood or OSB is nailed onto the beams, a roofing cake is laid (vapor barrier + basalt wool), a waterproofing layer and a rolled roof are directed.
If you are interested in a flat roof with a more complex device, please contact us: we will perform a roof of any complexity quickly and at an affordable price.
Flat roofs in our time are undeservedly forgotten and are not spoiled by the attention of developers. In private housing construction, they are found mainly in the southern regions, where heavy rains and snowfalls are rare. Hip roofs, on the other hand, have become firmly established in the designs and minds of homeowners.
This state of affairs is explained simply: until recently, builders did not have reliable and durable waterproofing.
Standard roofing material - cardboard impregnated with bitumen, cannot resist moisture and temperature changes for a long time. Even a thick 4-layer coating of it has to be changed after 6-8 years.
Today, interest in flat roofs is starting to grow.
There are several reasons for this:
- Economic benefit. The cost of arrangement is lower than that of a hipped roof (simpler design and smaller area);
- Additional usable area. There is the possibility of its rational use (flower garden, playground, recreation area, swimming pool);
- Availability for maintenance and operation (cleaning drains, installation of air conditioners, antennas, inspection of coatings, ventilation and smoke channels);
- The layer of snow plays the role of additional thermal insulation, reducing heating costs.
- The original appearance of the building.
Types of flat roofs
Strictly speaking, you will not see a completely flat roof on a building. Any of them has a minimum slope of 1 to 4%, which is necessary for the runoff of precipitation.
There are four types of flat roofs:
- unexploited;
- exploited;
- green (lawn);
- combined.
Unexploited roofs are found on industrial buildings.
Exploited roofs have found application in public and private construction. They equip recreation areas, place cafes and restaurants, use them as parking lots and helipads.
Green (lawn) coatings are made to decorate buildings, as well as when there is a shortage of space on the site. In addition to the aesthetic function, they perform an important practical task. A layer of vegetable turf is an excellent heat and sound insulator.
Combined roofs with a flat surface are the most common option. Everyone likes a comfortable outdoor recreation surrounded by green grass and flowering plants.
According to the method of drainage, houses with a flat roof are divided into two types:
- With internal drain;
- With external water discharge (along the perimeter of the roof).
Internal drainage is cheaper than external drainage, since it does not require a large number of gutters, pipes, funnels and high-altitude installation work. In execution it is more difficult. Errors in creating a slope, poor-quality sealing of joints lead to leaks and a violation of the integrity of the protective layer of waterproofing.
In operation, flat coatings with internal drainage are more profitable. In winter, icicles do not grow on the overhangs near such a roof. Downspouts run inside the building and therefore do not freeze. Cleaning funnels from debris is easier and easier than hanging gutters.
Device Features
According to the method of arrangement and the location of the structural layers, experts distinguish two types of flat roofs:
- Classic;
- Inversion.
The classic roofing "pie" is equipped according to the following technology:
- on reinforced concrete floor slabs, they make a ramp out of a cement-sand mortar;
- lay vapor barrier and insulation;
- lay a waterproofing membrane or roofing felt carpet;
- if the coating is to be used, then the waterproofing is protected with ceramic tiles.
Classic flat roof structure
The main disadvantage of the traditional design is the vulnerability of the outer insulating layer to solar ultraviolet radiation and temperature changes.
Working on a solution to this problem, engineers came up with the idea of inversion coating. In it, the main structural elements (insulation and waterproof membrane) are interchanged. Waterproofing is hidden under the foam, which is protected from external influences by a ballast layer of gravel or tile trim.
Inversion coating design
Accordingly, the technology of work is changing. A waterproof carpet made of roofing felt or an EPDM membrane is glued onto the slab or spread on it, fixing it at the junction with the parapet.
The slope in this case is created in one of two ways:
- Mortar screed on the plate;
- Insulation, changing the thickness of its installation.
Installation of thermal insulation on a flat roof
Water intake funnels and pipes are installed at the lowest points of the slope. In addition to them, ventilation is installed to remove water vapor that accumulates in the zone of contact between the vapor barrier and the insulation.
When arranging a coating designed for planting plants, the construct is supplemented with an upper layer of waterproofing. Drainage layers of gravel are poured along it, geotextiles are laid and a fertile layer of earth is poured.
In addition to roofing laid on reinforced concrete slabs, projects have been developed for houses with a flat roof on wooden beams.
Construction technology in this case may include the following operations:
- Beams are mounted on the walls in increments of 50-100 cm, fixing them to the masonry with anchor studs. The cross section of the beams depends on the width of the span, the design load and can range from 10x20 cm to 15x25 cm;
- OSB boards are laid along the beams, tightly joining them together;
- Spread the waterproofing membrane in 2 layers, gluing the joints of the canvases with high quality.
- They make thermal insulation from durable (extruded) foam plastic, gluing it to the membrane. A slope for water flow is created by laying the insulation in layers of different thicknesses;
- From above, the heat insulator is protected with a cement screed, reinforced mesh or tiled.
Examples of private houses
Among the developers there are many supporters of flat roofs. They are attracted by the ease of construction, the low cost of work and the possibility of placing a site for summer recreation.
A thick layer of snow on a flat roof is not a problem, but additional insulation
The design of buildings with such a roof fits perfectly into the style of minimalism, providing project developers with a wide field for creativity.
Spacious, comfortable and nothing more - the motto of everyone who chooses a house with such a roof. A pitched roof visually makes the building heavier, while a flat one, on the contrary, makes it light and airy.
The appearance of the facade of a one-story house with a flat roof compares favorably with the fairly boring variations of the "teremkovo" character.
On it, most often you will not see gutters and pipes, the water from which gets on the walls and spoils the appearance of the finish. Internal drainage is effective, practical and invisible.
When building your home, building a roof is one of the most important tasks. We propose to discuss how a flat roof is made in a private house with your own hands from corrugated board, its installation, insulation and drainage, as well as the advantages and disadvantages of this type of roofing.
Design features of a flat roof
Modern private builders rarely use flat roofs to cover private buildings, dwellings, mainly these are surfaces that can be covered with a gazebo, the surface of a garage, a bathhouse and other utility rooms. Mainly a flat roof is used for multi-storey residential buildings, where, due to design features, it is impossible to build a gable roof.
Photo - Flat roof roofing pie
Projects of houses and cottages with a flat roof are distinguished by originality and eclecticism. In addition, you can equip a special roofing cake, thanks to which the lack of attic (inter-roofing) space will play into your hands. There are such types of flat roofs:
Photo - Flat roof waterproofing There is also a flat combined roof - when the roof combines several of the listed types. For example, inversion and traditional.
pros flat roof:
- Very simple design, there are no special principles for installing rafters, frames and other beams;
- Easy calculation of roofing materials;
- You can use the surface of such a roof as a foundation for installing various systems directly on the roof: satellite dishes, winter gardens, solar panels, etc.;
- Smaller area, unlike a shed or attic (no need for wide overhangs).
But minuses flat non-attic roof are more significant:
- Due to the lack of an angle of inclination, it often leaks. Shed, gable and other sloping types of roofs do an excellent job of independently draining water, but for a flat one you need to build a special drain;
- Several times a year, a country house will need to be cleaned from the accumulation of foliage and snow on the roof;
- Often the funnels of the internal drain freeze due to the lack of an attic.
But still, in view of economy, the disadvantages that a flat roof has are not very significant compared to its advantages.
Video: flat roof
How to choose a material for a flat roof
Properly selected roofing materials for a flat roof are half the success of the entire construction of a house. Of course, you can stop at a profiled sheet, but it is worth noting that in this case it is necessary to think about how snow removal and drainage will be carried out. The fact is that from the constant exposure to atmospheric precipitation, the metal coating can rust and go out of service earlier than the period declared by the manufacturers.
The roof covering must be perfectly resistant to moisture. Here will serve well:
- Decking with a polymer coating;
- Polycarbonate;
- Slate;
- Mastics.
Let's consider what material for a flat roof is more often used. Construction mastics most commonly used on residential buildings. These are special liquid coatings that are applied to the surface of the roof with a brush, and then solidify, forming an airtight solid substance that looks like rolled materials. They perfectly resist high temperatures - up to 70 degrees, but can crack at low temperatures - up to 25.
Photo - Flat roof Polycarbonate is more reliable and beautiful than mastics, but it is much more expensive. Its main advantage is its external similarity with glass, so it can be used to create a stylish roof that will emphasize your financial condition. In addition, it is polycarbonate that is chosen for the design of residential buildings.
Slate previously used for any type of roof, regardless of its slopes. It is very heavy, so to install it, you need to carefully consider the frame and foundation of the building - so that the house does not “settle”. The load that slate puts on the rafters is perfectly compensated by its durability indicators: it can last up to 50 years in medium-aggressive environments with strong pressure and temperature drops. Now it can be replaced by aerated concrete, which is lighter.
Decking polymer coated is an almost ideal material for covering a flat roof. A dacha, a greenhouse and a house with such a surface may not be afraid of temperature changes, ultra-low degree indicators, but a snow cushion is fatal for them. It is necessary to ensure that the metal is periodically cleaned of precipitation, so work out natural cleaning systems.
Photo - Flat roof made of corrugated board More rarely, but still, a wooden flat roof is used. Its durability indicators are relatively low, but the tree will help protect the roofing material or the same mastics. Timber roofs are mainly used in complex design projects.
Flat roof installation
Consider how a flat exploited roof is installed on square houses, as well as how to insulate this type of coating.
A flat roof is a universal type of construction, it has an excellent combination of price and quality, but there are significant drawbacks in the form of a complex gutter system. When choosing such a roof, weigh all the advantages and disadvantages very well.
A flat roof in a private house provides many different possibilities. With such a simple design, you can save on roofing materials and work, and installation is carried out in a shorter time. It is also easier to place various systems on its surface: antennas, hoods, solar panels and others. In addition to all this, additional space can be used by arranging a garden, a recreation area or a greenhouse on it.
However, despite the cheaper installation, many nuances must be taken into account so that such a roof does not become a “headache” for the owner of the house.
Flat roof construction
A flat roof, like any other, must fully fulfill all its functions: protection from water and its removal and thermal insulation. In addition, it must have sufficient strength to withstand external loads.
This is what determines the structure of the roofing pie, which consists of the following mandatory elements.
- Base. All the main loads fall on this part. The overlap must be very strong, but it all depends on whether the roof will be used or not. Most often, the base is a reinforced concrete slab laid on load-bearing walls, less often on non-residential buildings - a layer of profiled sheet.
- Vapor barrier layer. Performs a protective function, which consists in preserving materials from steam penetrating from the inside of the room.
- Thermal insulation. Reduces heat consumption from the house.
- Waterproofing. A flat roof does not completely remove all the water, like gable counterparts, as a result, high-quality protection against the penetration of moisture in the room is needed.
For normal removal of moisture, a ramp is used. Most often, it is a screed, which forms the angles of inclination along which water can flow into the prepared system of trays to remove it from the roof plane.
Saving on any details of a flat roof is unacceptable, otherwise it will lead to leaks, freezing and other negative phenomena of a poorly mounted roof pie.
Types of flat roofs
The presence, order and sequence of individual elements of the roofing pie determine the type of roof. There are such designs of flat ceilings:
- Unexploited. These designs can be seen on multi-storey buildings. It is believed that their surface is not intended for use and is designed for a short stay of people. In this embodiment, on non-residential buildings, a profiled sheet can be used as a base.
- Exploited. In this case, it is necessary to have a concrete base capable of withstanding heavy loads. Surfaces can be used as a garden, recreation area or even car parking. In addition to a solid foundation, it is important to observe the angle of inclination, which should not exceed 3 degrees.
- Inversion. The design provides for a change in the order of the layers of the cake. Waterproofing is placed under the insulation, which allows you to save it from damage. Quite often, this type of roof is used in the construction of private residential buildings.
- Ventilated. These types of roofs have a ventilation system (built-in aerators) that evaporate excess moisture from the thickness of the roofing pie. Can be combined with other types of roofs.
In addition, the type of roof depends on other factors, for example, whether the room is heated or not.
Installation of a flat roof on different types of buildings
Depending on whether the room will have a heating system or not, the roof assembly technology may differ during installation.
Roofs on unheated premises
Usually, garages, sheds, gazebos, and various pavilions act as unheated buildings.
- The required slope of 3 degrees, on such buildings, is formed due to the load-bearing roof beams. The height difference is about 30 millimeters, per 1 meter of the beam length.
- After laying the beams, a flooring is made, which will serve as the base. It can be boards or profiled sheet. They are fixed with self-tapping screws or other suitable fasteners.
- If the room is unheated, you can miss such a layer as thermal insulation. A waterproofing material is laid on the base. Roofing material is used as a waterproof coating. It is spread out in overlapping strips (about 150 mm) and additionally fixed with slats, which are placed along the slope of the roof.
This is the simplest version of a flat roof, which can be mounted on an unheated utility room with your own hands at a minimum cost of money and time.
Flat roof assembly on heated buildings
In residential buildings with a heating system, the roofing pie of a flat roof will be different. It will definitely require the presence of a thermal insulation layer, high-quality hydro and vapor barrier. The presence of the latter is no less important, since water vapor can gradually spoil the entire roofing cake.
- The ceiling under the base is assembled from wooden beams, which are placed every 900-1000 mm.
- They are covered with flooring from boards with a section of 40-50 millimeters. The thickness of the lumber is selected depending on the distance between the beams. The larger it is, the thicker the boards are needed.
- A roofing material is laid on the flooring, it is cut and straightened in advance. Waterproofing sheets are overlapped by about 100-150 mm.
- The thermal insulation layer can be made by bulk method. To do this, expanded clay is poured onto the resulting base with a layer of up to 300 mm and leveled.
- Next, a cement-sand screed (at least 30 mm thick) is poured onto a layer of thermal insulation backfill.
- After the cement has hardened, the surface is covered with a bitumen-based primer and covered with a layer of roofing material.
It is also possible to mount a more solid roof made of monolithic concrete.
Monolithic concrete flat roof
In this embodiment, a solid concrete base is made by hand.
- As support beams, an I-beam is used, which is laid in level without forming a slope.
- For pouring, it will be necessary to prepare concrete of a grade of at least M250, it is prepared in a concrete mixer, maintaining a ratio of 4: 1.5: 1: 1, where the ingredients are crushed stone (20-25 mm), cement (m400), water and sand, respectively.
- For pouring, a base is made of boards, which are mounted on the lower shelves of I-beams and covered with roofing material.
- Small crushed stone is poured on top of the waterproofing, which is poured with the resulting concrete. Filling must be done at a time, otherwise the structure of the roof will not be the same.
- Next, expanded clay is poured and a ramp is made.
razuklonka
Razklonka is the formation of slight slopes on the surface of a flat roof, which allows you to remove water from its surface. The drainage system is assembled in two versions: external and internal. That is, the trays can be fixed to the end of the roof or on its surface.
With the internal location of the gutters, the presence of water collectors is planned in advance, the number of which is calculated as follows - 1 funnel per 25 square meters of roof area.