Insulating the attic from the inside if the roof is already covered. The need to insulate the attic roof The correct roofing of a residential attic

The roofing pie is a layer-by-layer structure made of covering flooring and accompanying materials. insulating materials, each of which has its own purpose. Types of materials included roofing pie, their location and number of layers depend on the finishing coating and roof configuration - flat or pitched, cold or insulated.

Purpose and composition of the roofing pie

Roofing cake is a filler for the rafter frame. Its main purpose is to protect the house from precipitation and provide a comfortable microclimate in residential premises. This is achieved thanks to the multi-layer nature of the roofing pie and the presence of forming elements, the correct installation of which, namely the order of arrangement of materials and adherence to fastening technology, determines the functionality of the roof.

Each layer of the roofing pie has its own purpose, is connected to the others and must be installed in a strictly defined sequence

Since everything is interconnected during the construction process - accuracy, reliability, combination of building materials, etc., you should remember an important rule - the weight of the roofing cake should not exceed the load-bearing capacity rafter system.

Hence the initial task - even at the design stage, to correctly assemble and calculate in accordance with standards 2.01.07–85 all the loads on the enclosing structure, the required thickness of the insulation and, in proportion to this, the strength of the roof truss frame.

By and large, the structure of the roofing pie is the same for all roofs. Typically it includes the following layers (from the inside out):

Depending on the type of roofing, individual elements may be added to the composition of the pie, for example, a lining carpet under flexible tiles. Or, according to the type of roof and its purpose, the arrangement of layers may change. In particular, when installing an inversion roof, the waterproofing is placed under the insulation.

Thus, for each roof there is a certain technology for laying the roofing pie, and only strict adherence to it ensures the durability of the entire structure. But just following the order of the layers is not enough. It is necessary that all materials are of high quality, tested and meet standards. And if everything is more or less clear with almost all the components of the pie, then problems often arise with vapor barrier, especially for novice developers who either lay material unsuitable for this purpose or abandon it altogether, having listened to the “wise” advice of people who have no practical knowledge. construction experience, but consider themselves specialists.

There is no multifunctional “vapor and waterproofing”, no matter what unscrupulous sellers tell you. Vapor-permeable waterproofing and vapor-proof membranes or films - different materials, the incorrect use of which will result in extremely disastrous consequences.

As for compliance with the methods of laying and fastening the components of the roofing pie, only one thing can be said here - the entire process is set out in the manufacturers’ instructions for each material . You just need to follow these instructions and not violate them.

Video: laying insulating layers of a roofing pie

Today thanks to modern technologies There are many ways to create a high-quality roof. Let's look at the most popular ones.

A roof is considered cold if the space under the roof is not insulated and is most often not used. In some cases, the attic space is left cold deliberately - arranging a wine cellar, food storage space, gym, workshop or bedroom, which will be in great demand on hot days.

In addition to attic roofs, there are also cold attic structures, crowning gazebos, terraces, the central entrance to the building, greenhouses, etc.

The device and composition of the pie for cold roof depends on its slope. For pitched roofs, the roofing pie is arranged in two zones: along the slopes and along the lower floor.

If you look from the inside, the sequence of layers on the slopes will be as follows:

• waterproofing material, fixed to the rafters;
• counter slats that fix the waterproofing and provide a ventilation gap;
• sheathing;
• roofing.

On floor slabs (from interior spaces to the under-roof):

For flat attic roofs, the layout of the layers remains the same, only the division is between the lower and upper floors. There is one peculiarity here - waterproofing is not included in the roofing pie and is not laid on the upper base, except for structures where wooden beams supported by walls and purlins serve as the base for the roofing.

The exclusion of waterproofing from the roofing pie for such configurations is fully justified. Soft roofing, which is most often used on flat roofs, is itself an excellent sealant. In addition, it fits roofing material on a solid base made of profiled sheets or concrete slabs, along which a ramp made of expanded clay or perlite and leveling cement strainer, which is quite enough to prevent any leaks.

Cold attic roofs are the most correct designs. They provide good natural air circulation, which is enhanced by roof aerators as needed. It is not for nothing that such roofs have long been built in Rus'. The entire roofing pie in them consisted of sheathing (modern lathing), stuffed along the bulls (rafters), and also laid on top of rough and red planks. Cold roofs can last hundreds of years, keeping everything usable. roof structure.

Video: cold attic roof pie

Pie for Shinglas soft tiles

Cold roofing with a wooden rafter system and high-quality soft covering "Shinglas" is often installed in private homes and administrative buildings. This design is easy to install, maintain and operate. The composition of the roofing cake includes:

As you can see, this design is very simple. Even one person can handle its installation, while saving on contractor fees.

Video: laying soft Shinglas tiles

Unlike cold roofs, all components of the roofing pie for insulated structures are combined into an integral system with the indispensable arrangement of ventilation gaps and a strictly determined alternation of materials. Layer arrangement of pitched pie warm roof as follows:

When installing a warm roof, it is necessary to properly seal the joints of all roofing materials in hard-to-reach and therefore problematic places - valleys, chimney and ventilation passages, dormer windows, adjoining walls. Poor tightness or its absence is fraught with roof leakage with the formation of fungus and mold, wetting of the insulation, rotting of the rafter system, heat loss through the roof and, accordingly, huge bills for energy resources.

Types of roofing pie relative to roof structure

Let's look at the features of the pie using the example of a pitched and flat roof.

Pitched roof pie

There are simple pitched and broken attic structures with a residential roof space. Simple pitched roofs have the roofing pie structure discussed above.

Video: correct roofing pie for a pitched roof

Features of the installation of warm broken roofs

Of particular interest are the broken lines warm roofs, although they have no global changes in the composition of the roofing pie and the typical layering of materials. The only difference is the location of the insulation and its eternal companion - the vapor barrier, which are laid along the slopes to the point of break, and then, as in a cold structure, horizontally along the support beams connecting the opposite rafters.

Thanks to this installation, a cold triangle is formed between the crossbars and the ridge, providing good ventilation of the attic, which is a necessary condition arrangement of a warm roof with a residential under-roof space.

The roofing pie of a sloping roof from top to bottom has the following structure:

Lately it has become fashionable to leave wooden rafters in the attic they are open, due to which in any pitched structures the location of some layers of the roofing pie changes. The order remains the same, but all materials, starting with the sheathing, are laid along the upper edge of the rafters, which must be taken into account when calculating the loads on the rafter system.

Video: roofing pie of an attic roof

Pie under a seam roof

A seam roof is a metal structure in which the panels (pictures) are connected to each other by bending (transverse and longitudinal seams). The grooves (grooves) formed in this case serve as drainage. This joining of sheets of aluminum, steel, copper and titanium-zinc looks charming on the roof of a house, and also creates a waterproof deck that reliably protects the roofing cake and rafter system.

Composition of the roofing cake for seam covering:

The peculiarities of the rebated pie are that the pie has a raised beam added to it, usually with a cross-section of 50X50 mm, laid along the upper edge of the rafters and providing an additional ventilation gap between the insulation and waterproofing, which is necessary to remove condensate from metal roofing. In sheathing, which for flat roofs and structures with a small slope is filled with a continuous deck using wood, particle boards or moisture-resistant plywood.

Since seam roofing, like any metal roofing, is classified as noisy, when laying the roofing pie you need to:

Video: installation of seam roofing

Pie flat roof

The construction of a flat roof is becoming increasingly popular due to the savings in financial, material and labor resources for its construction. In addition, this configuration is very effective in regions with frequent and strong winds- even a hurricane wind will not blow away a flat roof.

The structure of a flat roof pie depends on its base and method of use.

Unused flat roof

On a base of corrugated sheets, the layers of the roofing cake are arranged in the following order:

• galvanized steel base (profiled sheets);
• vapor barrier material;
• insulation;
• finishing coating.

Based on reinforced concrete slabs, the roof pie consists of:

Operable flat roof

You can move freely on the roof in use and use it at your discretion. Recreation areas are arranged on such a structure, winter gardens, playgrounds, swimming pools and even parking for cars. Naturally, a roof in use needs a solid foundation that can withstand significant loads, and correct installation all insulating materials.

Standard technology for placing layers of roofing pie:

The peculiarity of this layering is that the waterproofing is well hidden and will not be destroyed, and the insulation located between it and the geotextile is reliably protected from getting wet.

Green roof pie

In modern cities, thanks to intensive development, there has become a catastrophic shortage of green spaces. Private homeowners compensate for this deficiency by arranging green areas on their roofs - neat lawns and beds, bright flower beds and entire public gardens.

Creation green roof should be taken into account at the design stage of the house.

The composition of the roofing pie for a “living” roof is standard, with the only difference being that in this design 2–3 layers of geotextile are laid, which prevent weeds from penetrating into the base, preserving it from destruction. The layers are laid in the following order:

The green roof is an oasis of health and elation. But to equip it, you need to strictly follow the installation technology and use high-quality materials, otherwise repairs will be too expensive.

Despite all the advantages of slate, it is rarely used for arranging free-standing flat structures. The exception is transparent slate, the roofing cake for which consists only of sheathing and covering material.

Wavy slate due to its relatively low cost, they are more often used:

For the latter case, the roofing pie has the following composition:

Roofing pie for soft roofing

Today, soft roofing is in great demand among developers, due to its absolute tightness and a huge variety of materials that will make a roof of any configuration durable, reliable and attractive.

Based on texture, shape, color and composition of the top layer, 3 types are distinguished soft roof:

It cannot be said that some material is better or worse than others. They're just different. Each type has its own strengths and weak sides, therefore you should choose based on personal preferences and common sense.

For example, piece tiles are ideal for clearly visible pitched roofs. Roll materials are universal. Their new generation with a special technology for laying on pitched roofs resembles a seam structure. However, they are also good for flat roofs. And liquid drinks are, of course, the prerogative sloping roofs. In addition, soft roofing is a well-balanced combination of price and quality, which is why it is in high demand.

Specifics of the construction of a roofing pie for a soft roof

Roofing for soft coverings is more difficult than for hard structures. It is formed for each type of soft flooring, taking into account all indicators that affect the performance properties of the roof.

Some types of roofing pie for soft finishing materials have wooden components, so they cannot be installed close to smoke ducts.

The indentation standards are regulated by the standards of January 41, 2003, which recommend installing an apron made of galvanized or laminated metal around the pipes, and filling the empty space with non-flammable mineral wool material.

In addition, sheets of particle boards or plywood when arranging a continuous flooring are mounted with checkerboard seams, leaving a 3 mm gap between them to compensate for linear expansion in warm weather. And when filling a wooden sheathing, the boards must be placed with the convexity of the growth rings facing up - if for some reason the board moves, it will sag, filling the empty space, and not put pressure on the roof.

A typical roofing pie contains the following layers:

Video: connecting the membrane to the pipe

Installation of a roofing pie under a soft roof

Let's consider laying a roofing pie under a soft covering using the example of a cold and insulated soft roof.

Installation of a cold structure

Since the roofing pie of a cold roof is simple, it is installed easily and quickly.

On cold pitched roofs, it is permissible to lay underlay carpet only in problem areas. On flat structures, the lining carpet is spread over the entire area.

Installation of insulated soft roofing

The pie of a warm soft roof is more complicated due to the addition of heat and vapor barrier, but it also does not pose any difficulties in installation, since the arrangement of the layers remains unchanged.

The layout of the warm roofing pie will be as follows.

Video: subtleties and nuances of laying underlay carpet

Lightning protection mesh in the roof pie

Often, in the old fashioned way, a lightning protection mesh flat designs mounted in the roof pie under the insulation. Let’s say right away that such lightning protection is of zero use:

• the location of the lightning rod near the reinforcement of reinforced concrete slabs or load-bearing metal profiles is meaningless, since it is likely that the lightning current will overlap with metal elements;
• In this case, the covering material and roofing equipment remain unprotected and may be damaged by a lightning strike.

Properly equipped lightning protection is a mesh of semiconductors connected to lightning rods rising above the roof covering. Such a device provides many paths for the lightning charge to spread, which reduces the likelihood of lightning current breakdown on electrical installations and electrically conductive grounded parts of the building.

Many people advise making lightning protection yourself. The matter, of course, is the owner’s, but with factory equipment homemade assembly Naturally, it cannot be compared in terms of durability, reliability and manufacturability. Moreover, new developments in the field of lightning protection make it possible today to equip lightning protection grids that rise significantly above the coating. This will protect expensive equipment that ensures all vital functions of the house.

In conclusion, one piece of advice - do not skimp on installing a roofing pie. Any violation of technology will lead to unpredictable consequences, the least of which is heat loss and increased energy costs, as a result of which you will heat the street. Only high-quality materials, strict order, compliance with instructions and standards are the key to the longevity of the roof without additional costs for its maintenance and repair.

Externally, it is impossible to distinguish a house with a pitched roof, under which there is an attic, from buildings with an attic, unless skylights. But if you delve deeper into the roof design, you can find significant differences. Attic spaces are insulated only from the ceiling side, so as not to let out warm air from the living floor. Pie mansard roof contains many layers that allow you to create a microclimate favorable for living in the space under the roof.

First, let's figure out what is called a roofing pie. These are the necessary structural layers of the roof, which are laid in a certain sequence and are needed to insulate the structure, protect against condensation and moisture penetration from the street, and also as a base for laying the roof itself.

The roofing pie of a cold attic and a warm attic is significantly different. In the first case, fewer structural layers are used. Typically these include rafters, waterproofing, sheathing and roofing. When arranging residential attic spaces under the roof, the correct roofing pie consists of the following layers, located from bottom to top:

• interior decoration;
• vapor barrier layer;
• rafter system and thermal insulation material, which is laid between the rafters;
• waterproofing carpet;
• clearance for ventilation of the under-roof space (it is formed by laying counter battens);
• sheathing;
• roof covering, namely the selected roofing material.

Each of the listed layers performs its own specific functions, so the absence of a layer or its improper installation can lead to large heat losses and significant costs for heating the house. Due to the accumulation of condensation, the insulation can become damp, and the supporting structures of the rafter system quickly collapse.

Important! It is worth remembering that not only the presence of a certain layer and its correct installation is of great importance, but also the choice suitable material in accordance with the design features of the roof and the climatic conditions of the construction region.

Features of each layer

Next we will look at the attic cake layer by layer, indicating the design features, as well as the nuances of selecting and laying materials. We will consider all layers of the attic roof structure, moving from the room to the outside.

The very first layer, which is located on the side of the room, is the interior decoration. For these purposes, you can use sheets of plasterboard, plastic panels, wooden lining and other finishing. Among all the materials for finishing the attic, plasterboard and wood have an advantage, since they can naturally regulate the humidity in the room, which contributes to a favorable microclimate.

Vapor barrier

The vapor barrier layer is attached to the rafter system from below. It is needed to protect the internal structures of the roof and insulation from the formation of condensation due to temperature differences indoors and outdoors.

Attention! The absence or poor quality of vapor barrier leads to the accumulation of condensate moisture in the insulation. Due to dampness, the insulation cannot perform its thermal insulation functions, and the room will be cold.

Vapor barrier roll materials rolled out across the direction of the rafters and attached to them using a construction stapler. In this case, it is necessary to overlap the strips by 150 mm. The joints between strips of material are additionally sealed with special tapes or regular tape.

The following materials are used as vapor barrier:

1. The most accessible and inexpensive vapor barrier is glassine.
2. Over the years, its properties for protection against condensate moisture decrease, so it is better not to use it. Special vapor barrier membrane.
3. This is a polyethylene film that may have additional reinforcing and reflective layers. She copes with her tasks perfectly and does not sag. Foil vapor barrier.

This is the most expensive material, but in addition to protecting against moisture, it allows you to effectively retain heat in the room due to the reflective layer. The foil film must be attached with a gap of 10-20 mm from the insulation. To obtain this gap, before fixing the film, slats of appropriate thickness are placed on the rafters.

It is worth knowing: the vapor barrier should not fit tightly to the insulation laid between the rafters, so the material is attached to the rafters with a slight sag (about 2 mm).

Rafter system For making rafters In a private house, elements made of coniferous wood of at least grade 1 with a moisture content of no more than 15% are used. The optimal rafter section is 150x50 mm. In the middle climatic zone of our country for effective insulation for an attic roof, it is necessary to use thermal insulation material 200 mm thick. As you can see, a rafter height of 15 cm will not be enough, so a beam with a cross section of 50x50 mm can be attached to them from below.

The installation step of the rafter system depends on the roof structure, the width of the thermal insulation material used and the type of roofing. It is also worth remembering that the larger the pitch of the rafter system, the larger the cross-section of one element should be. For rafters with a cross section of 5x15 cm, the optimal pitch is 800-900 mm.

Important! All wooden elements The supporting frame of the roof must be protected from rotting and burning. To do this, they are pre-treated with antiseptics and fire retardants.

Insulation

The most important thing in the design of an attic roof is the insulation layer, because the comfort of living in the attic, as well as the level of sound insulation of the premises, depends on it. For thermal insulation pitched structures usually used:

• Mineral slabs. They are made on the basis of basalt fiber, are quite dense, non-flammable and retain heat well.
• Fiberglass is a non-flammable, environmentally friendly material. Its disadvantage is the instability of the structure and the possibility of sagging.
• Polystyrene foam is an inexpensive, effective material that does not absorb moisture at all, but releases toxic compounds when burned.
• Expanded polystyrene is a very light, non-flammable and non-toxic material that does not accumulate moisture. However, it has increased vapor permeability, so in summer attic floor There may be high humidity. Due to its high rigidity, expanded polystyrene is difficult to install on difficult areas of the roof.

Advice: to insulate the attic, it is better to use soft mineral wool slabs based on basalt. They are easy to install in difficult areas and fit tightly to the rafters without forming cold bridges.

For each construction region, the thickness of the thermal insulation material is calculated individually. The minimum insulation layer is 150 mm. For regions with harsh winters, it is necessary to use thermal insulation material with a thickness of at least 20 cm. In this case, the insulation is laid only on dry rafter wood. Otherwise, moisture will penetrate into the thermal insulation material and reduce its effectiveness.

Waterproofing

The main purpose of waterproofing is to protect the insulation from moisture penetrating from the roof, as well as the ability to transmit water vapor that will evaporate from the insulating material. This is why vapor barrier film is not suitable for these purposes, because it does not allow water vapor to pass through. Special materials are used to waterproof roofs:

1. Diffusion membranes. These are films with microscopic funnel-shaped holes. The material is laid so that the wide part of the funnel is turned towards the insulation, and the narrow part towards the roofing. In this case, it is necessary to create two ventilation gaps and lay the material away from the insulation at a short distance so that the funnels do not become clogged with water vapor. These membranes can only be used with those roofing coverings that are not susceptible to moisture collecting on the back side.
2. Superdiffusion membranes. The effectiveness of this material does not require the installation of an air gap on the insulation side. Such films are suitable for houses where the roof is laid on an already inhabited building. The membranes protect well from the wind.

Important! Both types of membranes cannot be used with Euro-slate and metal tile coverings, since their back side must be reliably protected from condensation. But for coverings made of soft and traditional tiles, these membranes are ideal.

1. Condensation films used for roofing made of euro slate and metal tiles, since they do not allow water vapor to pass through. In this case, excess moisture from the heat-insulating material accumulates on the fleecy side and is removed outside through the ventilation gap. In such structures, it is necessary to create a second ventilation gap between the waterproofing carpet and the coating so that condensation does not accumulate on the back side of the roof.

Counter batten and sheathing

If it is necessary to arrange ventilation of the under-roof space, then counter battens are placed on top of the waterproofing carpet. To do this, use a beam with a section height of 30-40 mm, which is nailed in the direction of the rafters.

Next comes a layer of sheathing. It can be continuous or sparse. The first option is installed under soft roofing coverings, for example, flexible tiles, and is made from OSB or moisture resistant plywood. A deformation gap of 2-3 mm should be left between the elements of the continuous sheathing. In the second case, 25 mm thick boards are used, which are nailed across the rafters in increments of 30-40 cm. After this, the roofing covering is laid.

If you insulate cold attic, used for storing unnecessary items, it will turn into a cozy residential attic. First of all, of course, you need to insulate the roof itself. The roofing pie of the attic roof is equipped more complex than a roof cold attic, but the result is worth it - the room can be used all year round. Here it is most important to fully comply with the technology, because each layer carries certain functions, without which the roof can suffer large heat losses without fulfilling its functions, or quickly collapse, as a result of which it will have to be completely redone.

Composition and sequence of layers of roofing pie

The attic roof pie consists of several layers, which are important to be placed in the indicated order from top to bottom:

• roof covering,
• sheathing,
• clearance for ventilation (counter-lattice),
• hydro and vapor barrier,
• rafters and thermal insulation,
• internal vapor barrier,
• interior decoration.

Material for thermal insulation: what to choose?

Thermal insulation is the most important layer of the cake, providing warmth inside the house. The thickness of the insulation layer is selected depending on the climate and region. The minimum thickness is 150 mm, but for regions where severe cold is possible, material up to 200 mm is used. Since we are talking about a slope at an angle, not any insulation is suitable for thermal insulation of the attic. The most commonly used materials are:

• Mineral wool slabs based on basalt fabric are a dense, non-flammable material that retains heat well.
• Expanded polystyrene is also a non-flammable material, environmentally friendly and fireproof. Its disadvantages include increased vapor permeability, which is why warm time There may be high humidity in the room during the year. Another disadvantage is that it is quite rigid, so it is difficult to install it on difficult areas of the roof.
• Polystyrene foam is inexpensive and effectively copes with the task of thermal insulation, and in addition does not absorb moisture at all. But it is a fire hazard, and moreover, when burned, it releases toxic substances.
• Fiberglass is also used as insulation, but its structure is not stable, so there is a possibility of sagging of the roof.

Sequence and nuances of installation

First you need to install the truss structure. If the heat-insulating material is selected in advance, then you can install the rafters with such a pitch that its slabs fit tightly in size - this will minimize waste, save money and simplify the insulation process.

The next step is laying a layer of hydro- and vapor barrier. Glassine can be used for this purpose, vapor barrier film or foil material. Most often they are sold in rolls, which will need to be rolled out parallel to the ridge, starting from the bottom. It is important to lay them overlapping each other, and be sure to seal all joints with connecting tape or tape. When laying, there is no need to tension the material; it should sag quite a bit between the rafters.

After this, a counter-lattice is made, which acts as a ventilation gap, using counter-battens, which are nailed or fastened with self-tapping screws to the rafters.

This is a necessary element, since lack of ventilation can lead to:

• melting snow on the roof in winter, and the formation of dangerous icicles and ice,
• elevated indoor temperatures in summer, turning the attic almost into a bathhouse,
• increased humidity of the insulating material, which reduces its effectiveness and increases the risk of mold or mildew.

You can also use roof vents in the rafters and ridge aerator- a device that is located along the upper edge of the roof. All its cracks must be covered with a grill to prevent debris from entering.

After this, the main layer - insulation - is laid. It is important that at the time of this action the rafters are completely dry - otherwise moisture from the wood will be absorbed into the material, reducing its ability to insulate.

The slabs are laid in two layers. This is due to the fact that wooden or metal rafters become a bridge through which cold penetrates into the room. To prevent this from happening, the insulation is first laid between the rafters, and then another, thinner layer of heat-insulating material is made. In order to further be able to attach the necessary elements to the rafters, you need to mark their location on the material.

All that remains is to attach a layer of vapor barrier, after which the insulation of the attic can be considered complete and we can begin interior decoration ceiling.

Metal tiles are roofing materials made from sheets of steel, copper or other metal.

The material has a wave-like structure of various configurations.

This material is coated with a protective coating.

In order to cover the roof with metal tiles, it is necessary to provide correct under-roof space.

When arranging the roof important indicator its functional purpose is roofing pie.

They call it a roofing pie set of layers, of which the roof is laid. Depending on the purpose of the room(warehouse, industrial, residential) number of layers and method of laying them may change.

How are metal tiles constructed? The roof pie under the metal tiles is laid in the following order:

• (roof frame, made, as a rule, from wooden beams, serves as the basis for applying layers of roofing cake);
• (prevents moisture from entering to roofing pie);
• (provides heat preservation in room);
• (serves to ensure dryness of the room, prevents moisture from entering the room(waterproofing films, membranes));
• counter-lattice;
• sheathing ( wooden frame , which is applied and transfers the roofing load to the rafters. The sheathing has a pitch smaller than that of the rafters, and the beams are laid perpendicular to the rafter boards);
• (external roof covering, providing protection of the roof from atmospheric influences, wind, dust, moisture entering the room: metal tiles, ondulin, corrugated sheets).

In addition, between the layers of the roofing cake they are arranged.

Each layer separately has its own laying characteristics.

Sheathing pitch for metal tiles and counter-lattice

The sheathing is a solid or lattice roofing decking that provides base for laying roofing layers.

How to calculate the step?

To calculate the amount of material consumed per sheathing, you need to know the step lathing etc. The step size is affected by the wavelength of the coating. The sheathing pitch is the distance between the boards of the structure.

When laying with gratings, determine the pitch based on the dimensions of the roofing covering.

It should be borne in mind that the distance from the edge of the roof (first board) to the second board should be less than the pitch along the entire perimeter of the roof. Sometimes two boards are attached in a row from below in increments of 1-2 cm, and then lay out the boards with the pitch calculated for a given type of tile.

In this case, the metal roof pie consists of the following layers:

• rafter system;
• thermal insulation;
• sheathing;
• counter-lattice;

An important indicator of durability, warmth, and quality of roofing covering for metal tiles is correct layering, ensuring air gaps in the roof and choosing the material used.

You should not skimp on materials, since their quality is one of the conditions for ensuring high-quality roofing and warmth and dryness in the room as a whole.

Today in the “Drawings and Schemes” section, Evgeny Zvyagintsev, our friend from Novosibirsk, presents his version of the attic. His design of the roofing pie is based on the use of soft tiles - one of the most used roofing materials today.

Below is a drawing of the roofing pie (projection from the pediment):

So, let's look at the presented drawing. Roofing pie from top (from the street) down (towards the room).

The first layer is a roof covering made of bitumen shingles. As is known, flexible tiles- This is a roofing material, on the fiberglass base of which a layer of bitumen mastic is applied, sprinkled with mineral chips. The material is easy to install and has the best performance among roofing materials for roof waterproofing. However, it also has disadvantages. Soft tiles are a flammable material. This imposes certain restrictions on its use. It is also necessary to additionally insulate the roof slope when installing a chimney, for example. In this case, the chimney is equipped with a spark arrester.

You can read more about the installation of a chimney in the “Heating” section - there are drawings of penetrations with steel and brick chimney soft roof.

Next in layers - lining material and plywood. Soft tiles are a plastic and fairly soft material. Therefore, it requires a solid base for installation on the roof. This base is plywood, which takes on snow and wind loads. At the same time, the plywood is reliably protected from precipitation and ultraviolet radiation by bitumen shingles.

Plywood for the base under the roof soft tiles you should choose a moisture-resistant one. This will avoid warping of the roof plane.

The plywood is mounted on the sheathing - this is the next layer of the roofing cake. For lathing, use a 100x25 mm or 75x25 mm board. A board of greater width, such as for lathing under metal tiles, is not used here - this does not make sense with a solid plywood base.

There is a wind protection under the ventilation gap bars. It also functions as a waterproofing system in case of possible leaks if the roof is damaged. What is good about a roof made of bitumen shingles is that even with strong side winds and rain, not a drop of moisture gets under the roofing material. Therefore, we install a windproof membrane with a waterproofing function (just in case).

Next come the rafters. Sheets of roofing insulation are laid between the rafters. In the standard design of a residential building, the height of the rafter leg is 150-200 mm. It is this thickness that the insulation is used (usually several layers of 50 mm each).

If this is not enough, then the next layer is provided - a lathing made of 50x50 mm bars for attaching an additional layer of insulation. Thus, it is possible to insulate the attic with up to 250 mm of high-performance insulation.

Now let's look at the same drawing in projection AA (from the ridge to the overhangs):

Here you can clearly see how the lower layer of additional insulation is used to cover the upper layers, which are laid between the rafters. This makes it possible to clearly remove possible cold bridges, which in this design are the wooden parts of the rafter system. Thermal insulating properties different breeds We have already looked at wood using the example of thermal conductivity tables on our website.

As can be seen in the second drawing, the ventilation gap bars are packed vertically on the roof - this ensures air flow from the bottom up (from the overhangs to the ridge) along the roof.