Metal tiles - light, durable, effective roofing material, perfect problem solver low-rise construction. Its steel endurance is perfectly combined with undeniable technological advantages. Laying large-sized sheets is done tens of times faster compared to piece-meal competitors. It lasts a long time and does not require a powerful base.
You can install the roof and build a simple frame for installation with your own hands. There will be no difficulties in your work if you know how a gable roof works - rafter system under metal tiles and the installation process must take into account technical and technological features coverings.
Metal tiles belong to the class of rolled products. In essence, it is the old familiar sheet steel, profiled in two mutually perpendicular directions. The longitudinal and transverse waves formed as a result of profiling give the sheets a similarity to the ceramic roofing prototype. Outside equipped with a colored polymer film that performs protective and decorative functions.
Disadvantages of the material and ways to eliminate them
The ability to imitate roofing ceramics did not rid the material of the standard disadvantages of metal. Thin sheets quickly heat up under the sun's rays and quickly say goodbye to the heat at the slightest drop in ambient temperature. There is no insulation: heat and sound waves easily penetrate inside the steel roof and go outside unhindered. The list of disadvantages is significantly supplemented by the ability to collect condensate due to the difference in the thermal properties of the coating itself and the rafter frame elements in contact with it.
Low insulation performance and condensation are two “scourges” of a metal roof. You can get rid of them by arming yourself with information about the proper construction of a frame with a correctly laid roofing pie. If the installation of the rafter system for metal tiles is carried out in accordance with all technological requirements, complications with laying the material and operating the structure will not arise.
To ensure that the traditional behavior of a steel roof does not bother owners and does not cause premature wear, it is necessary to correctly distribute the layers roofing pie. Responsibility for distribution lies with the rafter system, the list of responsibilities of which includes:
- Retention of the components of the roofing pie, which are laid on top, below and between the rafters.
- Formation of air channels that eliminate condensation, and often the possibility of its occurrence.
- Preparation of a number of supports aligned in one plane for the installation of future slopes by laying profiled sheets.
If we figuratively compare the roofing system with a living organism, then let’s say this: the “patient” will live and function normally only with a healthy supporting apparatus. In our case with a rafter frame. The method of dealing with the shortcomings of a steel coating lies precisely in choosing and strictly following an impeccably suitable installation scheme for the rafter system for the subsequent installation of metal tiles.
Types of rafter systems for metal roofing
Roofs with metal tile covering are erected over permanent and temporary residences. Gazebos, verandas, and bathhouses covered with metal “scales” look interesting. Depending on the purpose of the structure and the conditions of its operation, roofs with metal tiles are installed with or without insulation. The presence of thermal insulation is closely related to the structure of the rafter frame:
- For insulated roofs, a system is constructed that includes three insulating layers and one or two ventilation circuits.
- For cold roofs, a system with one insulating layer and one ventilation circuit is installed.
Insulated roof structures are erected if planned all year round actively use the attic. Rafter frames warm roofs calculated so that they are located in the space between the rafters. Analogs without insulation are installed on small dachas and buildings intended for temporary residence.
A roof without thermal insulation is also constructed in the case of insulation attic floor. For example, above a bathhouse or residential building with a low attic space that is clearly not intended for use, it is more reasonable to lay insulation between ceiling beams or above them.
In the construction of rafter frames, rolled metal and lumber are used for laying profiled sheets. Hardware properties are closer to coatings, but wood is more suitable for the tasks of private construction. It is easier to work with it for an independent owner who has decided to build and cover the roof with his own hands.
It’s easy to make all the frame elements yourself from lumber, assemble and connect them into a rafter system. Wood is warmer and more attractive in terms of environmental aspects.
Advantages of a gable design
The most simple option In the construction of a rafter system for laying metal tiles, a design with two slopes is rightfully recognized. Her rectangular planes ideal for laying sheets of similar shape. The hip or one will require much more effort with diligence. Many owners are depressed by the increased consumption of large-sheet material for roofing structures with full-length and shortened hips, and are not happy with the complexity of cutting.
Manufacturers claim that the optimal design for laying metal tiles will be a design with a slope angle of 12 to 15º. Structures of lesser steepness must be equipped with a reinforced waterproofing carpet. On steeper roofs, the number of fasteners increases and the installation step decreases. In both situations, the budget for the arrangement will be increased due to the purchase of additional insulating materials and hardware products.
Depending on the size of the metal tile and the dimensions of the structure being installed, the sheets are laid in one, two or more rows. Laying in one row is a priority, because transverse seams reduce insulation parameters and are potentially dangerous for leaks. Manufacturers consider the best sheet length for arranging the roofs of private houses to be 4-4.5 m. Among the offers of most metal tile suppliers there is a very popular service for cutting sheets to size, which is incredibly convenient for laying on slopes with custom sizes. The length of the sheet is equal to the sum of the length of the slope and the length of the overhang, which is 0.4-0.6 m, depending on the architectural solution.
The metal tiles are mounted on the sheathing, which in turn is attached to the rafter system. The lines of all structural parts of a gable roof are strictly vertical and horizontal, which significantly facilitates the process of laying profiled sheets with similar edges. If the rafter system is built without flaws, then there will be no problems with installing the sheathing and roofing.
Construction of the rafter system
We found out that the rafter system works in tandem with the roofing pie. The layout of the rafter frame is directly related to the number of “cake” layers. Let's analyze the most complex insulated design option and find out which components we do not need to build a cold roof.
The rafter structure of a gable roof is a series of alternately installed pairs rafter legs, design features which depend on the architectural data of the box being equipped. Manufactured and produced in accordance with the rules regulated by:
- Layered technology, requiring two specific supports for the top and bottom of each rafter leg. It is used if the building has an internal load-bearing wall or rather powerful columns are installed instead. The use of the layered method is allowed if the ridge girder racks can be installed on the floor beams with a high bearing capacity or if the ceiling is made of reinforced concrete slabs.
- Hanging technology, requiring support only for the bottom of the rafter legs. The top of the elements of the hanging rafter system rests against each other in pairs. It is used if the box does not have an internal load-bearing wall and the ability to install supports under the ridge girder.
Option #1 - rafter frame for a warm roof
The use of insulation forces one to resort to technological tricks, thanks to which the layer important for the structure can retain its insulating qualities. And they will inevitably shrink when wet, because... The water that appears in the body of the material will facilitate the passage of heat waves.
Water appears in thermal insulation in three situations:
- Penetration of household fumes attacking thermal insulation from inside the structure being used.
- Formation of condensation due to the difference in temperature outside the building and in the attic.
- Leaks observed during snowmelt and heavy precipitation, resulting from non-compliance with technology and operational errors.
A properly laid roofing pie, correctly distributed and securely fixed by the rafter system, is simply required to eliminate the listed misfortunes. In addition, the responsibilities of the rafter structure include the formation of ventilation channels through which air flows wash the thermal insulation and the inner surface of the metal tiles.
Ventilation channels created by installing lathing and counter-lattice create conditions for regular ventilation and removal of condensate from the space under the roof, thereby prolonging life cycle the roof itself and wooden parts rafter system.
If we imagine a conventional cut of a warm roofing pie with a rafter system from the inside of an already finished structure, then the sequence of layers and ventilation ducts will be as follows:
- Lining, plasterboard panels or similar material used for interior decoration attic space.
- Internal lathing designed to secure the vapor barrier layer to the rafters.
- Vapor barrier that prevents household fumes from penetrating into the insulation.
- Rafters between which insulation is laid. The width of the rafter leg should be 3-4 cm greater than the thickness of the thermal insulation. In other words, the specified gap for ventilation must remain between the upper plane formed by adjacent rafters and the outer surface of the insulation. If the thickness of the insulation is equal to the width of the rafters, i.e. The thermal insulation lies flush with the conventional plane of the slope; a lathing made of timber with a side of 30 or 40 mm is nailed to the rafter legs. This will create the required gap.
- Waterproofing, which is laid either on the rafters, if there was no need to install a counter-lattice, or on a counter-lattice. Classic polyethylene waterproofing film It is forbidden to come into contact with the insulation so that moisture does not appear in the body. Waterproofing materials of the class of polymer diffuse membranes are allowed to lie directly on the insulation, because they are able to let excess moisture out without letting it in. Therefore, when using polymer membranes, there is no need to create a ventilation channel between the hydro- and thermal insulation.
- External sheathing that simultaneously performs three significant functions. It is used for fastening waterproofing, to form another vent between the waterproofing and the metal covering and serves as the basis for installing sheets of metal tiles.
- Finish coating.
Bitumen varieties of rolled materials cannot be used as waterproofing of roofing systems under metal tiles and corrugated sheets. When heated, the insulation and roofing will release substances that destroy each other's structure.
Let's summarize. A standard roofing pie for an insulated roof has three layers and two ventilation circuits, if classic waterproofing was used in construction. There are three layers and one ventilation channel in a cake with polymer diffuse waterproofing. All components are attached to the rafter system, which must withstand the weight of the materials and the snow load. For domestic middle zone the total load is approximately 200 kg/m².
Most often, rafter legs for metal roofs are made from boards with a cross-section of 50×100 or 50×150 mm, if the rafter installation step recommended by the material manufacturer has been followed. If the distances between the rafter legs are greater than the recommended value, the cross-section of the outer sheathing should be increased.
The diagram of a roof structure without insulation clearly confirms that it does not contain a heat-insulating layer. This means that there is also no need to install all types of insulation protection from getting wet. However, waterproofing is still needed to protect the wooden rafter system in case of leaks. And ventilation between the water-repellent material and metal coatings should also be built.
A cross-section of a cold roofing cake for metal tiles looks like this:
- Rafter legs, the cross-section of which is calculated without taking into account the weight of the insulation and related components.
- A waterproofing layer laid over the rafters.
- Lathing designed to provide a ventilation gap, fix waterproofing and fasten sheets of metal tiles.
The sheathing for both types of rafter systems is laid in a special way. The step of its installation is determined by the distance between adjacent transverse steps of the metal tile sheet. The distance depends on the brand of roofing, on average it is 300, 350 and 400mm.
The dimensions of the starting lath should be different from the subsequent ordinary bars. For example, if all ordinary laths are made of a block with a cross-section of 30x50mm, then to make the very first element from the eaves line you need to take a block of 50x50mm. The distance between the starting block and the cornice line is always less than the step between the row laths. So it is necessary that the first transverse step of the sheet lies exactly on the base.
Video instructions for installation work
The video will clearly introduce you to the process of constructing a rafter system and installing metal tiles:
The diagrams for the construction of rafter systems with insulated and cold roofing pies, disassembled “on the shelves,” represent a general guide to the actions of an independent roofer. In fact, designs are modernized and adapted to the real conditions of a particular facility. However, they may well serve as the basis for your own development.
Rafters, or otherwise rafter legs, are the skeleton of the roof.
Its basis.
And therefore, the viability of the roof depends on how correctly the parameters of the rafter system are calculated, how correctly its calculation and installation are carried out.
Depending on what one of the roof functions is planned: an attic or a cold attic, what roofing material is to be used, the rafter system may change.
If you have to lay it on a residential building natural tiles, then the rafter system must be reinforced.
And if you need to lay corrugated sheeting on a shed, then a lightweight system will do.
From a geometric point of view, the truss structure is a set of triangles.
In order to make a rafter system the right size need to know:
- slope angle;
- section of the board from which the rafter legs are made;
- their length;
- sizes of different supporting elements.
One of the most important indicators, which has a great influence on the strength of the system and its stability, is .
That is, the distance at which they are located from each other.
For private residential buildings, this value is usually taken from 60 to 100 centimeters.
The distance between them is greatly influenced by a large number of all sorts of factors.
Therefore, an accurate calculation of this parameter is required.
The calculations are made in the following sequence:
- Measure the length of the roof slope. Then you should divide the resulting value by the approximate foot.
- One should be added to the resulting value and rounded to big side the resulting number to the nearest integer. In this way, the number of rafters for one roof slope of a certain length is calculated.
- Now the existing length of the slope should be divided by the resulting number of rafter legs. We get the exact distance between them.
Which is usually called a step.
- The axis always runs through the center of the rafter.
You should know that the gap between the rafters for different types roof covering may vary.
Even if the length of the slope is the same.
Pitch for different roofing materials
Under metal tiles
Metal roofing is one of the most common roofing solutions for private houses today.
This material, which is an imitation of natural ceramic tiles, has many advantages over its original:
- metal tiles are lightweight and do not require a reinforced rafter system;
- the low weight greatly simplifies the installation of metal tiles and the installation process is much faster.
The small mass of metal tile sheets made it possible to make more simple compliance most frame parameters.
For example, you can significantly reduce the thickness of the base material, reduce the cross-section of the beams on the sheathing, and make the installation step of the rafter legs larger.
If you are going to use metal tiles as a roofing material, then the installation interval of the rafters can be in the range of 0.65 - 0.90 cm.
Just enter the parameters of your roof into certain fields and you're done!
But you should know that programs and online calculators There are both free and requiring payment!
Video about installation of the rafter system.
Sergey Novozhilov is an expert in roofing materials with 9 years of practical experience in the field engineering solutions in construction.
The gable roof design for private houses is most often chosen, since it is the best option in terms of ease of installation and ease of use, strength and reliability, as well as style solutions. A gable roof is also called a gable roof and has two slopes, which can be located in relation to each other at the same or different angles, that is, the front can be an isosceles or scalene triangle. The latter option can increasingly be found among new buildings, as it is becoming a fashionable style solution. And, in addition to originality, such a roof has some positive features, which simplify its operation.
This type of rafter system can be used for all types of roofing materials, but the sheathing attached to the rafters has its own parameters for each covering.
Gable roof: the rafter system for metal tiles, which has its own characteristics, must be carefully studied and calculated in advance, before purchasing materials and installing it. Let's try to understand these issues.
Types of gable roof designs
- 1 Types of gable roof designs
- 2 The main components of a gable rafter system
- 3 Types of gable roof rafter systems
- 3.1 Layered rafter system
- 3.2 Hanging rafter system
- 4 How to calculate the parameters of a gable rafter system
- 4.1 Loads on the rafter system
- 4.2 Angle of slope of the rafter system and height of the ridge
- 4.2.1 Ridge height calculator
- 4.3 Length of rafter legs
- 4.3.1 Calculator for calculating the length of the rafter leg
- 4.4 Calculation of the pitch and cross-section of rafters
- 4.4.1 Calculator for calculating the distributed load on the rafter leg
- 4.5 Parameters of other lumber
- 5 Sequence of installation of the rafter system for metal tiles and roofing
- 5.1 Video: erection of a gable truss structure under a metal tile roof
First, you need to understand what types of gable roof designs there are, since you will have to choose the most suitable one for a particular building.
- Simple equilateral gable design
This version of the gable design can be called traditional and the most used, since it is easy to install and maintain, and is also durable and reliable.
Symmetry in this system helps to achieve uniform load on the Mauerlat and load-bearing walls. At making the right choice beam sections for arranging the rafter system and the Mauerlat, these parts will provide the safety margin necessary for long-term operation of the roof. Additional reliability of the structure will be provided by correctly installed racks, struts and tightening.
The disadvantage of this system for arranging inside the attic space is that after installing the walls and ceiling large area occupy blind areas in the corner areas of the structure that remain unused.
- Simple asymmetrical gable design
The asymmetrical gable design differs from the traditional system in that its slopes are located at different angles. So, one of them is usually more than 45 degrees, which allows you to increase usable area attic space, in which it is quite possible to arrange a living space, of course, with proper insulation.
Another important advantage of such a design may be a smaller slope, which is recommended to be planned on the leeward side of the building, where a large amount of snow always accumulates on the roof. A slope that is small in size but has a great steepness will not retain large snowdrifts on its surface.
The disadvantage of an asymmetrical structure is its more complex calculation to achieve uniform distribution of the load on the walls of the house.
- Broken gable structure
This gable rafter system can be called a rarity, although due to this arrangement of the slopes in attic space sufficiently formed a large room, which can be used for residential or commercial premises.
In addition to such a rafter system, a broken gable structure can also include attic option installation of rafters.
An attic broken rafter system can provide a building with a full second floor with spacious rooms, and with enhanced insulation they can be used at any time of the year.
The main components of a gable rafter system
Now let's look at the main structural elements of the gable roof rafter system
In the vast majority of cases, when repairing a roof, the choice falls on metal tiles.
In addition to the long list of economic and operational benefits, this material It is also interesting for its suitability for self-installation.
Even basic skills will be enough home handyman so that the roof is not only durable and practical, but also attractive in appearance.
Advantages of metal tiles
The widespread use of metal tiles is due to the combination of the following advantages in this type of roofing material:
- Economic expediency.
Compared to most other roofing coverings, metal tiles have a relatively low cost.
What makes purchasing such a roof even more profitable is the ability to avoid hiring builders to install it, as well as its long service life. - Light weight.
With an average weight of 1 sq. m of material is about 6 kg, the total mass of the roof is relatively small. This allows you to do without the use of a powerful and expensive rafter system. In addition, a lightweight roof does not require the installation of continuous sheathing, which simplifies the calculation of the roof and reduces the cost of work. - Resistance against external factors. Protection is provided by use in the design roofing sheet a few protective words. Therefore, the metal base of the canvas is not afraid of prolonged exposure to moisture, direct sunlight, or damage during installation or hail.
- Aesthetics. The production technology of metal tiles allows you to create absolutely any texture. Accordingly, on the market you can easily choose an option that suits the overall exterior of the building. The range is further expanded by the possibility of painting sheets in all shades of the palette.
- Fire safety. The basis of the metal tile is a sheet of galvanized steel. This material is completely non-flammable, making it absolutely fireproof.
The indicated advantages of metal roofing make it the most practical, affordable and attractive externally a roofing option.
Materials and tools
To install metal tile sheets, you will need a set of traditional tools for finishing work:
- electric screwdriver;
- jigsaw or circular saw;
- marker;
- construction stapler with staples;
- metal scissors;
- scotch;
- laser plane builder or construction level;
- roulette.
Important! To cut sheets of metal tiles, you cannot use grinders with abrasive discs operating at high speeds. Their use will lead to overheating of the steel base, melting and destruction of the polymer protective coating. Such damage greatly reduces the service life of the roof.
Of the materials, in addition to the metal tile itself and its accessories, you will need the following:
- bars 50 x 50 mm;
- boards 100 wide and 25–35 mm thick;
- sheet waterproofing material;
- wooden slats;
- galvanized screws, nails.
Funds will also be required personal protection and auxiliary equipment: ladder, scaffolding, brush for sweeping away debris, etc.
Find out more about laying corrugated sheets on a gable roof:
Structure of the roofing “pie”
The basis for creating a roof made of metal tiles is rafter system. In a gable (or gable, as it is more often called in everyday life) roof, the rafter system has the most convenient configuration for installation work, since it forms only two planes.
A layer of waterproofing material (3) is laid on top of the rafter system. Without it, moisture condensing on a metal roofing sheet will be absorbed into the wooden structures under the roof, destroying them. Waterproofing also helps in cases where the roof begins to leak.
Vertical slats - counter-lattice (4) - are attached to the waterproofing material along the rafters. Their purpose is to organize a ventilated space between the waterproofing and the sheathing.
In addition, the roof structure contains frontal boards (8) and eaves strips (10). The first ones are stuffed onto the end part of the rafters (1) and protect from moisture falling with the wind. The latter serve to remove moisture flowing down the waterproofing layer.
Installation procedure
On gable roofs metal tiles are laid first on one slope, and then on the other.
Laying sheets of metal tiles should begin with lower slope angle.
All installation work on roofing is carried out in several stages:
Checking the geometry of load-bearing roof elements
At this stage, the diagonals of the roof slopes are measured and compared using a tape measure. If they coincide, then the roof has a rectangular shape suitable for laying metal tiles.
In addition, you need to use a level or builder to make sure that the ridge and both cornices are strictly horizontal. The flatness of the slopes must also be checked. Emergency sections of the rafter system are being repaired.
Installation of the frontal board and filing of the roof overhang
The place where the front board is attached (8) is the end (bottom) part of the rafters (1). This is fixed roofing element galvanized nails.
Front boards should not completely isolate the under-roof space from the street. To ensure free passage of air, ventilation gaps must remain between them.
A horizontal sheathing is installed on the reverse side of the front board under the roof overhang. As such, you can use perforated plastic panels. This option is convenient because it allows you to use fastening j-straps for plastic, nailed to the front board from behind. If boards are used, ventilation slots should be left between them.
Installation of gutter hooks
Hooks(9) should be placed in a straight line with a slope towards the planned drainage. Reliable drainage will be ensured by the slope angle from 5 mm per meter of gutter. 
The most practical and easy to install are hooks of extended length. They are sewn to the bottom of the rafters on top of the front board. To provide vertical arrangement hook, grooves of the required depth are cut in the board and the bottom of the rafters.
First nailed or screwed to the top of the rafters top part hook Then it is bent to the required position and fixed on the end of the rafters. If the installation of the drain is carried out after laying the metal tiles, then use short hooks, the upper part of which is under roof covering does not start.
Laying waterproofing material
Rolled water-repellent materials (films) are used for the roofing “pie”. As it moves onto the rafters, the roll unfolds horizontally along the eaves. You should start from the bottom of the roof. Each subsequent strip is laid with an overlap on the bottom one. The amount of overlap is 15 cm.
The waterproofing sheets (3) should be fixed with a construction stapler. The material is allowed to sag up to 2 cm. The joints are taped. The top and bottom of the film are determined by the factory markers applied to it.
Along the rafters on top of the waterproofing they are stuffed vertical(4) and horizontal(6) laths made of wooden strips. They are nailed along the central part of the rafter beams.
Attention! Metal roofing and bitumen waterproofing are incompatible materials. When the roof heats up under the sun, the bitumen will melt and the canvas will lose its ability to repel moisture.
Find out how to make a gable roof gable with your own hands:
Installation of sheathing
The bars or boards of the horizontal sheathing begin to be packed from below, from the eaves. The first beam of the sheathing must have a cross-section larger than the cross-section of the remaining beams. When installing it, it is necessary to control strict parallelism to the cornice. Installation of metal tile sheets begins with fixation on lower beam battens. Therefore, the appearance of the entire roof will largely depend on the accuracy of its installation.
The pitch of the sheathing beams depends on the distance between the horizontal waves on the metal tile sheet and must coincide with it. Most often the pitch is 300, 350 or 400 mm. The only exception is the step up to the second beam of the sheathing. Here it should be reduced by 70 mm. 
The most top bars the battens are also stuffed with decrease step, right up to nailing the beams tightly. This will make it easier to install ridge elements and add strength the entire structure. Around roof and dormer windows, chimneys, ventilation ducts and other additional elements(bridges, snow guards, etc.) the sheathing should also be strengthened by stuffing a continuous web of beams.
Installation of curtain rods
The planks are attached along the entire cornice using galvanized self-tapping screws. The fastening pitch is 300 mm. If the length of one bar is not enough, then it is increased. In this case, the planks are laid overlapping with overlaps of 50–100 mm.
The eaves strip is attached with a slight tension, then the roofing material will be more resistant to gusts of wind and less noisy.
Installation of the lower valley
Where the roof planes (for example, the slope of the roof of a house and the slope of the roof dormer window) form intersections under small angle, the installation of a special strip is required - the lower valley (20b).
A continuous plank sheathing (7) is placed under it. Boards with a cross section of 150 x 25 mm are applied as lathing material.
Under the lower valley you will need a continuous strip of sheathing about 300 mm wide.
The position of the lower valley is selected so that its edge in the overhang area passes over the cornice board. The sheet of metal tiles and the lower valley strip are not directly fastened together, but are laid with porous insulation.
Installing a chimney outlet bypass
For brick pipe the procedure will be as follows:
- A layer of waterproofing is applied around the perimeter with an overlap of 50 mm on the pipe. For fixation, you can use heat-resistant tape;
- bypass strips (28) are installed;
- A groove about 15 mm deep is cut along the pipe, into which the upper edges of the bypass strip are inserted. You can only tap on solid bricks; it is prohibited to do this on masonry joints;
- The drainage bar organizes the drainage of water, which either drains into the nearest valley or is directed to the eaves.
The decorative pipe surround is not installed at this stage of the work; metal tiles are laid first. For round chimneys, the lining is made of sealing tape. To ensure a tight fit to the pipe, the tape will need to be cut along the top edge in several places before gluing.
Installation of metal tile sheets
If it is possible to lay sheets along the entire roof slope in one row, the installation order will be as follows:
- the outermost sheet is applied and its position is verified relative to the eaves and side section of the roof;
- the first sheet is fixed in the upper part with one self-tapping screw;
- the next sheet is laid with an overlap in the wave and aligned vertically;
- the sheets are sewn together with self-tapping screws, but the threads should not be screwed into the beams;
- the following sheets are mounted in the same way;
- the resulting assembly is once again verified relative to the ridge and cornice;
- screws are screwed into the sheathing.
If the height of the sheet is less than the length of the slope and you have to lay the metal tiles in several rows, the procedure will be as follows:
- the first two sheets are laid according to the same pattern as for single-row installation;
- the third sheet is placed on top of the first with a horizontal offset of 150 mm, after which these two sheets are fastened together;
- the next sheet is placed above the second and attached to it horizontally. With the third sheet, fastening is carried out on the vertical side;
- four fastened sheets are aligned together and fixed to the sheathing by tightening the screws.
At the final stage fixation produced at the bottom of each wave by bottom cut sheets. In places where vertical overlap, screws are screwed into crest waves. Distance between self-tapping screws should be chosen with this calculation: there should be 6–8 pieces per square meter.
For detailed instructions on installing metal roofing, see this video:
Dormer window device (“cuckoo”)
The location of the "cuckoo" is determined early. When laying sheets of metal tiles, areas corresponding to configurations dormer window.
Roofing pie under the window neatly sawed out. By perimeter windows are being installed additional sheathing beams.
Gaps between the timber and the sheet of metal tiles are sealed. To drain water, install valleys the top and bottom of the dormer window.
Installing the end strip
The purpose of this slats(29) – protection from precipitation and sharp gusts of wind penetrating under the metal tiles. In addition, the end strip also performs decorative function: when correct installation its upper edge overlaps crest waves of metal tiles. Screw end strip start from the side of the cornice. If it is necessary to build up, provide an overlap in 100 mm.
Installation of the upper valley
The purpose of this element is to drain water, in addition, upper valley(20a) makes roof joints more aesthetically pleasing.
For installation, use self-tapping screws, screwing them in so that don't disturb waterproofing layer. Between the upper valley panel and the surface of the metal tile, a self-expanding insulation.
Installation of junction strips
These planks allow you to organize careful And sealed transition from the roof surface to adjacent walls and other structural elements buildings and roofs.
The connection to the wall is arranged according to the same principle as the connection to the chimney.
Installation of ridge strips and external corners
Before installation ridge strip you should make sure that the gap between the waterproofing sheets of adjacent roof slopes is not less than 20 cm. On top of the top continuous sheathing you can lay additional layer waterproofing material strip of 150 mm.
Fastening is carried out with self-tapping screws screwed into sheathing through the covering wave. To increase the ridge strip, organized overlaps, serving as additional ribs rigidity.
End parts of the ridge are closed external corners, fixed with self-tapping screws. Between metal tiles and ridge strip is laid insulation made of elastic material.
Installation of stairs, walkway, roof railing and snow guard
Roofing accessories made of metal tiles are mounted on top of the roofing.
Their places placement are determined in advance and are intensifying additional beams and sheathing boards.
Particular attention is paid to installation snow guard(21). It is fixed to the rafters complete reinforced screws.
Installation of a drainage system
When installing water drainage systems The following rules should be followed from the roof:
- to one drain pipe it is forbidden install more than 10 meters of drainage gutter;
- Part gutters above the funnel should be cut at an angle with sides in 100–110 mm;
- funnel should be located under the gutter at a distance of 150 mm.
All elements drainage system, including plugs, funnels, etc., have a fixation system among themselves. However, after installation work is completed, they should be further processed. silicone sealant.
Attention! Drainpipes are mounted with crimp down, otherwise leaks cannot be avoided.
Roof grounding with a separate bus
Since metal tiles have the ability to conduct electricity, then for safety reasons it should be provided with a system grounding.
Grounding is done by connecting electrical wires large section with one end to the roof (through a self-tapping screw). The second end is securely attached to metal structure buried in the ground depth at least a meter.
Post-installation processing
Metal tiles require periodic inspection(semiannually). From the roof and drainage system clean up debris and leaves, and the surface cleanse soft brush.
Canvas in problem areas Can tint, this will increase its corrosion resistance.
Installing counter battens under rafters
The system of counter-battens under the rafters allows you to insulation roofs. They are used as counter rails wooden beams
or planks nailed.
Further into the space between rafters a layer of insulating material is placed behind the counter-trikes, which additionally reduces noise metal roofing.
Laying vapor barrier and fastening with slats
Leave insulation open is unacceptable, since moisture can get on it and negate the entire insulating effect. To prevent this, apply to the insulation vapor barrier film (16). This material does not allow moisture to pass through, but effectively allows water vapor to pass through, leaving the insulation dry
Wooden slats are placed on top of the vapor barrier for fixing whole pie.
Safety precautions
Work on installing the roof of gable roofs refers to work with high level of danger, and the more slope stingrays, the stricter the safety requirements. Don't neglect them, take care of yours health:
- be sure to wear safety belt, tied with a strong rope to a strong part of the building;
- work in shoes that have good clutch with surface;
- stairs And forests securely fasten to the walls of the house;
- roof protect scaffolding, scaffolding, mesh or sides with a height of at least 1 m.
When working with metal tiles the following rules should be adhered to:
- always use mittens;
- to not allow applying excessive force to metal;
- take into account the strength of the wind and windage sheets of metal tiles.
In addition, it will not be superfluous to use all available devices that make work easier. Eg, inclined guides from long boards will not only increase safety when rise sheets, but will also ensure the safety of the material.
In general, installation of metal tiles on gable roof does not pose a serious problem. It is enough to follow safety rules and follow all recommendations to get reliable And beautiful roofing at the lowest possible cost.
The following describes the safety rules that must be followed when working with metal tiles: video:
Roofing made of metal tiles attracts with its appearance. The advantages of the material also include light weight, ease of installation and affordable cost.
Calculation of the roof frame and rafter pitch
One of the key factors determining the resistance of the roof frame to loads is the pitch of the rafters - the distance between adjacent rafter legs located on the same slope. The more accurately the rafter pitch is calculated, the more durable and more reliable design roofs. In addition, you should select the correct cross-section of rafter legs and other structural elements. Errors in calculations can lead to the fact that during operation the roof is deformed under the influence of external loads.
The rafter leg must be strong and rigid in bending. Its length and cross-sectional size correlate with each other: the longer the rafter, the larger its cross-section should be. The length of the rafter leg is determined based on the angle of inclination of the slope and the height of the ridge. When calculating the gap between the rafters, you should also take into account the angle of the roof - the steeper the slopes, the greater the pitch of the rafters can be. But when long length rafter legs, the distance between them should be reduced.
The gap between the legs is on average 80-100 cm, with a rafter pitch of 60 cm being considered the acceptable minimum, and 150 cm being a reasonable maximum. To determine the optimal number of rafter legs on the slope, perform the following steps::
- the length of the wall on which the rafters will rest is measured;
- the resulting value is divided by the most suitable step;
- One should be added to the result and the resulting value should be rounded up.
This algorithm allows you to calculate the required number of rafters for one slope, and to find out at what interval they will be installed, the length of the wall should be divided by the resulting value. The result will be equal to the center-to-center distance between the rafter legs, which is the pitch of the rafters.
It should be noted that the general methodology does not take into account such nuances as the choice of insulation. By adjusting the pitch of the rafters to the width of the insulating roll or slab material installation can be simplified roofing system and reduce construction costs. The size of the gap between the rafters can be adjusted to certain limits - you should not increase the calculated pitch of the rafters when constructing a rafter system for heavy roofing materials.
The rafter system for metal roofing, on the contrary, does not require special reinforcement. This material for external roof covering is characterized by sufficient high strength with relatively low weight. Sheets of metal tiles are mounted on a sparse sheathing of bars or boards, which is attached to rafters located in increments of 60 to 95 cm. These are average values for rafter legs made from a standard board with a cross-section of 50×150 mm, with a length of up to 4.5 meters.
If you intend to use a heat insulator with a thickness of more than 150 mm, it is recommended to make rafter legs from boards with a cross-section of 50x200 mm, so that you do not have to increase the width of the rafters with slats from the attic side.
Features of installing a frame under metal tiles
In general, the rafter system is calculated and installed according to standard rules. A fundamental feature can be considered the need to fasten the upper support of the rafter leg on top of the ridge girder, and not in the side of the ridge beam. In this case, in the upper part of the roof, in the ridge, there remains free space necessary for normal air circulation in the roofing pie. If proper air circulation in the system is not ensured, condensation will form inside the roofing pie, causing corrosion of the metal tiles.
To make the air exchange of the insulated roof more intense, it is recommended to drill holes with a diameter of about 10 mm near the upper edge of the rafter legs.
The construction of a roof frame made of metal tiles may require the use of elements to strengthen the rafter system. The elements that impart rigidity to the structure usually mean tie rods and crossbars - horizontal jumpers between the rafters in the system hanging type. The tie is located at the base of the rafter legs, the crossbar is closer to the ridge. Reinforcement of layered rafter legs is carried out by installing horizontal purlins on racks - this provides an additional point of support. TO additional elements include fillies – special boards, allowing you to increase the size of the rafters in length to form an overhang of a metal tile roof.
When installing a wooden rafter system, it is important to take care to protect the wood from damage by rot and fire. Antiseptic impregnation will prevent biological destruction wood materials, A fire retardant composition will reduce the risk of fire and the speed of fire spread. For processing truss structures after assembling the frame (or individual elements before its installation), complex fire-bioprotective impregnation or separate specialized compounds can be used.
The treatment is carried out in two passes with a break for the first layer to completely dry. The composition is applied with a roller or soft brush.
Installation of a metal roof frame
The frame of a metal-tiled roof of a private house is most often built from wood - this material is easily adjusted to size and installed without the use of specialized equipment. However, the device supporting structure under metal tiles, in some cases it can be made from metal profile. In particular, during construction:
- garages;
- hangars;
- pavilions;
- gazebos;
- outbuildings.
Metal profile rafters for metal tiles have a number of advantages:
- withstand high loads;
- allow the installation of long beams (more than 10 meters) without additional supports;
- the design does not propagate combustion;
- the frame is durable (with proper installation and protection against corrosion);
- allows us to produce reliable roof structure non-standard configuration.
To the disadvantages completely metal roof The high thermal conductivity of the material should be attributed - the frame acts as a cold bridge. That is why a metal roof is most suitable for non-residential buildings that do not require heating. In addition, the use of metal profiles significantly increases the cost of construction.
The high strength of the metal profile and its bending rigidity makes it possible to cover spans with big size, without installing supporting structures. This simplifies the installation of the roof.
If metal rafters are to be used, the entire roof frame must be metal. A channel is used as a Mauerlat, to which the lower ends of the rafters are subsequently welded. The frame is made according to the project independently, or ordered at production. In the second case, the accuracy of geometric dimensions and the quality of welding are higher, but the finished structure will have to be installed on the walls of the building using lifting mechanisms. Installation of a frame from individual elements makes it possible to adjust them on site.