Roofing on floor slabs. Hip roof on floor slabs

That warm air rises up, every schoolchild knows. Based on this, it can be assumed that a significant part of the heat that the house “loses” evaporates through the roof.

Therefore, reducing heat loss must begin with roof insulation.

The type, quantity and method of installation of insulation depends on the type of roof and how the attic space is used - residential or not.

The requirements for insulating a residential attic are certainly higher than for a non-residential one, so in this article we will focus on the insulation of a residential attic. Non-residential attic it is easier to insulate - from the ceiling or along the floor. At the same time, we will focus on two types of roofing – pitched and flat.

It is easier to insulate a pitched roof from the inside of the roof, since access to the rafters is open. Plus, the requirements for thermal insulation materials are lower.

First you need to choose the type of insulation that will combine optimal properties– cost, efficiency and reliability.

Popular modern materials for insulation of roof slabs

1. Soft insulation – mineral or basalt wool

If such a material is chosen for roof insulation, then mineral wool of the required thickness is selected.

Manufacturers provide the buyer with a wide choice various materials, which have different densities and geometric dimensions. Choose the one that suits you specifically in terms of price and parameters. The only drawback of cotton wool is its hygroscopicity.

This means that cotton wool absorbs water, and therefore its quality is greatly reduced. Therefore, cotton wool must be protected from water from above and from steam from below. This necessitates the use of two types of film - a vapor barrier and a hydrobarrier. They can be replaced with a universal superdiffusion membrane.

Technology of roof insulation with mineral wool

If a hydraulic barrier is laid on the rafter system, then sheets are laid between the rafters mineral wool, which are closed from below with a vapor barrier.

If there is no water barrier, then first, a water barrier film is nailed to the rafter part with a stapler. It is important to attach it with an overlap; for this purpose there is a marking on the roll.

Then a wooden beam equal in thickness to the thickness of the insulation is stuffed onto the rafter leg.

Insulation is placed in the resulting cells. Mineral wool should be laid tightly, but not knocked down. After all, insulation occurs, including due to the air gap, which is obtained due to the structure of the wool. And if you lay it tightly, there will be less air and the properties of the wool will deteriorate.

It is convenient to attach cotton wool to wood using a nylon cord or thin wooden slats. Next, the cotton wool is covered with a vapor barrier film.

The roofing pie is shown schematically in the figure.

Tip: You can save time and money if you install rigid insulation instead of a moisture barrier. And then you mount the cotton wool on it, with the obligatory use of a vapor barrier film. However, this approach is only possible if the roof is well installed. Otherwise, any leakage will negate all savings.

2. Rigid insulation - polystyrene foam or polystyrene foam

This material is used more often, not because its thermal insulation characteristics are higher, but because it is easier to work with. After all, it is light, cheap, easy to cut and does not absorb water at all. This means there are no costs for protective films.

When choosing polystyrene foam or expanded polystyrene as roof insulation, it is worth remembering that these materials are fire hazards and emit acrid smoke when burned.

Polystyrene foam is installed by laying slabs in the gaps between the rafters. In this case, the sheets are laid tightly, and the cracks are filled with foam.

Tip: If you want to improve the quality of your work, give preference to thinner and denser foam. However, lay the sheets in two layers in a checkerboard pattern.

3. Liquid insulation – liquid penoizol

Liquid penoizol is a relatively new thermal insulation material that has already been appreciated by professionals. Insulation with penoizol, with a competent approach, guarantees a high protective effect for many years.

Processing with foam takes little time, while the efficiency is incredibly high. Liquid insulation Penoizol is sprayed (applied) onto the inner surface of the roof using a special installation.

The thickness of the applied layer can vary as desired. Penoizol does not need additional protection. And most importantly, it is not flammable, does not get wet and is lightweight.

Using these materials, you can also insulate the attic floor.

Helpful advice: When choosing insulation, do not put price at the forefront. In this type of work characteristics are more important material and quality of installation.

It is important to choose not only the type of insulation, but also to correctly calculate its thickness. Which should be optimal. On the one hand, sufficient to ensure heat retention. On the other hand, so as not to overpay too much.

To do this, carefully read the characteristics and properties of the material and take into account the characteristics structural elements buildings, temperature in winter period, wind strength and direction, amount of precipitation in the region.

Many houses are built in a style traditional to Western European countries. Namely, with the arrangement flat roof. Which, most often, is reserved for leisure areas (for example, for a device or).

However, a flat roof also needs insulation, just like a pitched roof. But its insulation has some nuances. The most important of them is creating a slope.

On a completely flat roof, water will have nowhere to go except to evaporate or seep down. But a slope of 1.5 - 4 o will not create any inconvenience for roof users.

The slope of a flat roof is performed using expanded clay. The direction of the slope should lead to water flow to the funnels of the drainage system.

When laying, it is important to ensure that there are no tears in the film.

The insulation is selected and installed. At the same time, it must not absorb water, withstand point loads, and not lose its qualities due to temperature changes.

soft insulation. The most popular is high-density Rockwool. It can withstand high temperatures and significant point loads, while being easy to install and providing the ability to fuse the roof.

rigid insulation. Even the density of polystyrene foam is not enough to withstand heavy loads. At the same time, rigid insulation materials are flammable.

liquid insulation. Withstands high temperatures, loads, is resistant to ultraviolet radiation and biocorrosion.

It is more convenient to insulate the roof slab of a flat roof from the outside. To do this, heat-insulating material is laid on top of the floor slab or corrugated sheet (example in the photo).

After completing the insulation, you can thus plant lawns on the roof and arrange elements landscape design or equip cafes and recreation areas.

Insulation of roof and attic floors - mistakes and ways to eliminate them

Error	Elimination
Wrong choice of insulation	Involvement of a specialist at the material selection stage
Incorrect calculation of insulation thickness	Taking into account all factors that affect heat loss in the house.
Actually lower percentage of heat loss than calculated	Presence of cold bridges. Concrete structural elements, window and door openings, metal parts of dowels are the causes of cold bridges through which a significant part of the heat escapes.
The appearance of mold, mildew	Poor quality installation of the hydrobarrier or vapor barrier film. No counter racks.

Conclusion

High quality and proper insulation covering the roof will reduce heat loss in the house, or even use the attic as a used (warm and residential) room.

The roof is one of the main components of any structure. It serves not only for protection from precipitation and thermal insulation, but also to give the building a completed shape. Currently, roofing technology depends on its type (flat, pitched), materials and equipment used.

The minimum slope of a metal roof should be 14 degrees.

Flat roof

The traditional arrangement of layers in a flat roof structure.

This type of roofing is widely used in both residential and industrial buildings. It is good because it has simple installation, affordable cost and additional usable area, which can be used to set up a cafe, sports ground, parking lots, growing green spaces, etc. The drainage is usually internal to the house, and the edge is delineated by a parapet. Roof slope up to 3% to ensure better drainage of rain and melt water.

There are two ways to construct the base of a flat roof: concrete floor(monolith or concrete slabs) and beam (as with a pitched structure, but with minimum angle tilt).

The concrete floor must have thermal insulation in the form of sheets stone wool or foam, which are laid on top of the roof base. The next layer is a reinforcement screed. The structure is completed with a waterproofing coating.

This type of flat roof is very reliable and durable; it can be used as a terrace, but the disadvantage is the large weight, which implies strong foundation and durable load-bearing walls building.

Beam construction method flat roofs has rafters at the base ( wooden beams or I-beams made of metal), and on top the flooring is made of plywood or OSB. Insulation is placed between the beams.

Compared to a concrete roof, beam floor less reliable and over time can cause deflection, leading to deformation of the roof.

Waterproofing coating for flat roofs

The structure of waterproofing a flat roof on a concrete floor.

Among the varieties waterproofing coating For flat roofs, a membrane system can be distinguished. The PVC membrane is made from plasticized polyvinyl chloride and a number of other components that reduce the flammability of the material, protect it from ultraviolet radiation and oxidation during high temperatures environment. It consists of two layers: the top one contains dyes that give it light color, reflecting the sun's rays, as well as fire retardants, stabilizers, plasticizers and filler. The bottom layer is darker, without fire retardants and stabilizers. To make the membrane stronger, it is reinforced with fiberglass or polyester mesh.

The following tools and equipment are used to cover the roof with a PVC membrane:

Automatic welding machine for joining seams of panels.
Manual welding gun (used when welding membrane joints in hard to reach places, at the junctions).
An electric drill if you need to screw in screws or other fasteners to secure the membrane.
Perforator (for mechanical fastening of the membrane if the base of the roof is a cement-sand screed).
A construction gun used for installing membranes when working at height from ropes or scaffolding, since in this case working with a hammer drill is impractical.
Electrical extension cords for automatic welding machines.
Consumables and auxiliary materials (construction knife, gloves, screwdriver, etc.).

The technology for attaching a PVC membrane can be carried out in several ways: heat welding, adhesive, ballast and mechanical.

The heat-welded method of joining sheets is made using welding machine, which produces a stream of air with heating of 400-600 degrees. The recommended welding seam width is from 20 to 100 mm.

Advantages: high-quality sealed roof surface, UV rays do not affect welds.

Disadvantages: the complexity of the process, which should only be trusted to specialists.

Fastening PVC membranes with adhesive is used in cases where other methods are unacceptable for some reason.

Special adhesive mixtures which are applied to the canvas. To save money Money, connection can be made adhesive composition only in the most key places (roof perimeter, membrane junctions with chimneys, in-house storm drains and other protruding places).

The roofing membrane, used as waterproofing, is reliably protected from exposure to ultraviolet radiation, high and low temperatures by gravel ballast.

Advantages: adhesive technology for installing PVC membranes is good for roofs with complex structures.

Disadvantages: possibility of poorly glued seam, high price glue mixture.

The ballast type of installation of PVC membrane sheets is the easiest, acceptable for roof slopes of up to 15 degrees. The fastening technology consists of the following stages:

Uniform laying of membranes on the roof surface, fastening along the perimeter in places adjacent to vertical elements by welding or glue.
Laying ballast (crushed stone, gravel or medium-fraction pebbles) weighing from 50 kg/m2.
Protection membrane material mats or non-woven fabric from mechanical damage(the action is performed before adding ballast if it has sharp edges).

Advantages: simple and economical installation.

Disadvantages: The roof must be strong to support the weight of the ballast.

Technology mechanical installation membranes involve attaching the sheets to the base of the roof with fasteners - self-tapping screws with a plastic umbrella. They are screwed in in areas where one membrane sheet overlaps another with a pitch of 200 mm. Along the perimeter of the roof, the membrane is attached to the protruding elements with edge strips.

Pitched roof

The most popular solution for constructing a roof is gable roof, whose attic space is not heated.

The name itself suggests that the roof has a slope (with a minimum angle of 10°). The size of the angle depends on the architectural design of the building, roofing material and the amount of snowfall in the area being built.

Classification:

Shed - one slope between parallel walls.
Gable - two rectangular slopes having a common connection.
Four-slope (tent, hip) - four triangular slopes connected by vertices at one point or two trapezoidal and two triangular parallel to each other.
Broken (attic), conical and other complex-slope structures.

Pitched roofs can be made in two versions: with a warm or cold attic. Device base ( Basic structure) consists of rafters (wood or metal) or reinforced concrete slabs.

Design of two pitched roof: rafter legs, tightening, purlin, stand, bench, mauerlat.

The main element of a pitched wooden or metal-wood roof is the rafter system. It is calculated from the weight of the roofing material, the load of precipitation and wind.

Rafters. Rafters can be layered or hanging. Mainly used wooden rafters from timber coniferous species, because they are easier to process than reinforced concrete or metal.

Mauerlat. The beam on which the legs of the rafters rest is called the Mauerlat. It serves as a support and is mounted along the entire length of the building. A waterproofing layer is laid between the Mauerlat and the inner surface of the walls.

In order for the roof of a building to have high resistance to wind loads, the mauerlat and rafters must be well fastened to the walls with anchors and metal corners.

Runs. They are attached parallel to the Mauerlat. There are ridge ones (the ends are connected rafter legs) and side (mounted in the middle of the rafters).

Racks. Wooden beams located perpendicular to the ridge of a pitched roof. They provide support for the rafter legs and transfer the weight to the tie.

Puff. A beam installed perpendicular to the Mauerlat along the base of the device rafter system. Serves to enhance rigidity.

Sill. It is an additional stiffener and is installed if rafters are installed on two spans at the same time.

Struts. Another component of the rafter system to increase its rigidity. They can be transverse and longitudinal.

Lathing. The boards or beams that are laid across the rafters are called sheathing. The roof covering is attached to the sheathing.

The construction of a pitched roof made of reinforced concrete slabs consists of individual elements, which are manufactured at the factory and assembled into a single unit at the construction site. This type of roof is mainly used in the construction of industrial buildings.

Classification of roofs by type of roofing materials

Soft bitumen roofing

Materials serving as protective and decorative coating, called “soft roofing”, have high consumer demand due to wide choice colors, light weight, flexibility, resistance to precipitation, although the cost of such a coating is quite high. These include bitumen shingles, rolled materials (polymer, bitumen), roofing felt, membranes. Service life is at least 20 years.

Types of hard roofs

To rigid materials pitched roof include different types metals (steel, copper, aluminum), mineral materials(tiles, slate, slate tiles), wooden (tips, shavings, shingles).

Regardless of which roofing device you choose, you must approach each stage of construction competently and efficiently: from the drawing to the final. Each installation technology has its own advantages and disadvantages, but as a result correct application will give good result for many years.

Semyonovich, I couldn’t find an answer to this question on the internet. Coven. at the workshop made of reinforced concrete, total area 80 by 24 meters, slope approximately 5 degrees, filled with bitumen. It is proposed to tie the rafters directly onto it with wire to the floor slabs. But I can’t imagine how. It is clear that you need to drill holes in the slabs, but how to insert the wire into one hole and pull it out again into the next one in order to tie the rafter? It’s impossible to walk down there, there’s nothing to walk on. Maybe there is another real and simple way to attach the rafters, please advise. Insulation between the rafters is also expected.

Alexey, Vologda.

Hello, Alexey from Vologda!

A very non-standard question is how to secure wooden rafters to the workshop span. Therefore, the answer to it is not visible on the Internet.

More and more of these are simply re-coated with roofing felt (rubemast, glass insulation and the like) directly over its old layers, including the layer of poured bitumen. Sometimes these old layers of roofing are torn off. But this, of course, is difficult. New electrical installations completely attach the roofing material to the old one without removing it. But they are still a rarity for our great and vast country.

I admit that I have never blocked workshop spans using your method.

Smaller areas were also available in several other variations.

At the same time, we laid wooden beams (and boards), an analogue of your rafters, and attached them to reinforced concrete slabs not with wire, but in a slightly different way.

They took a steel corner with a shelf about 63 - 75 millimeters, cut it with a grinder into pieces 50 - 100 millimeters long. Holes were drilled in these scraps along both shelves. Holes for self-tapping screws /2 - 3 pieces/ were made in the vertical shelves (about 5 millimeters in diameter), and in the horizontal shelves one hole with a diameter of about 12 - 14 millimeters. (As an option - take steel sheet 1.5 millimeters thick, cut into strips, then bent into a corner and holes were drilled).

After this, the trimmings of the corner were applied with a vertical shelf to the surface wooden beam and attached it to it with self-tapping screws.

And the second horizontal shelf lay on the surface of the reinforced concrete slab.

Through a hole in the bottom flange of the corner, a hole was drilled in the slab or through hole(when it was opposite the cavity cell of the slab).

Then they took anchor bolts(you can use a wedge anchor), inserted into the hole, and drove with a hammer. Then, using a drill with a head for the bolt, they screwed the anchors in until they stop. True, the number of anchors was decent, but they are not cheap.

We got a completely normal fastening. The following features were taken into account.

First, we calculated the approximate pitch of the reinforcement that was in iron concrete slabs Oh, the ceilings, so that you can’t get into them with a hammer drill and you can put an anchor in them.

Secondly, when looking from below, the view was not always presentable; in some places, potholes were visible on the surface of the slabs (where the hammer drill hit large crushed stone, component concrete, and it fell out.

Third, the rafters were not immediately attached to the slabs, but the longitudinal joists. And only then rafters were laid on them and secured with staples, nails, and screws. This results in fewer fastening points, which means less labor intensity.

All pieces of wood were impregnated with KSD, "Senezh". This is what the customer required in accordance with the regulations. Experienced customers always carry out author's control and often require the use of not colorless compositions, but with color. Then you can see whether there is coverage or not. You know, coven-makers are not always scrupulous in this matter.

I can't say anything about other methods. You can, of course, lay it out along the rafters, drill holes next to them with a hammer drill and, driving around overhead crane inside the workshop bay, insert the wire into these holes and twist it. But this is somewhat difficult. Yes, and there may not be a crane, but you can’t jump with a ladder.

But this is all speculation on a free topic.

Now what would I personally do if I were you?

In your case, floor slabs are most likely used. If memory serves, with spans like yours, their dimensions are about 9 meters by 1.5 (or 1.8) meters. The load-bearing reinforcement in such slabs is located around the perimeter. And throughout the area there is welded mesh with a large cell. Wire diameter is from 3 to 5 millimeters. The plate itself has stiffening ribs. And the thickness varies around 50 millimeters.

The slabs are supported on reinforced concrete arch-trusses. The joints of the slabs along the grooves are interlocking or simple.

Then it is most advisable not to use logs, as we did with conventional rectangular flat reinforced concrete floor slabs, but to use them for rafters edged board cross section 40/150 millimeters. Lay it flat on the surface. “40” is more suitable here than “50”; it bends better. Laying, respectively, from the edge to its center.

Then the sheathing boards can be taken in measured, six-meter lengths and placed lengthwise without any bends.

Press the rafter boards firmly to the surface. That is, secure one end of the board, then a couple of people from the team should stand on the other end of the board. It will curve and hug the slope of the roof. Then fasten the next anchor bolt. The fastener pitch is about 1.5 meters. Drill holes for anchor bolts directly into the boards at their centers. And then drilling into the slabs themselves.

The anchor should also be driven in with a hammer and screwed in with a drill with a head. It is most likely not advisable to use a screwdriver; its power may not be enough. To prevent the head of the anchor bolt from falling into the wood, you can play it safe and put a washer under it large diameter. The length of the anchors should be approximately equal to the total thickness of the board, bitumen layer, plus the thickness of the floor slab.

There should not be many different kinds of holes along the perimeter of the roof in order to exclude the so-called windage, when the upper wind enters a confined space and is capable of tearing the roof away from its base. Extreme events like this are rare, but they do happen.

Everything proposed does not quite fit into SNiPs; they would recommend placing the rafters on edge for greater rigidity, using a 50/150 board, adjusting its surface to the slope, and using an edged board, also 50 millimeters thick, as a sheathing. Or remove layers of old roofing material, make a concrete screed, or even completely tear off the old floor slabs and install new ones with a new layer of soft roofing. But your customers are unlikely to pay such costs.

I repeat once again that you may have simple reinforced concrete slabs, or maybe floor slabs, and accordingly, the mounting options may be different.

Focus on the circumstances. Try it, experiment.

As for the insulation, there won’t be any special problems. Isover, ursa, mineral wool, polystyrene foam, whatever your heart desires. If you observe all decency, then you need air gaps, various thermal films, in worst case glassine and all this on the counter-lattice. If the insulation is soft and 50 millimeters thick, then it’s okay, the “40” board will work just fine, you just need to press it down a little.

However, this is my vision. The decision is still up to you to make.

Garage slabs

Typically, slabs are used in the construction of a stone garage. They are laid directly on the masonry walls, on a previously laid out layer of cement mortar.

Since the slab is fed by a crane and held by it by weight, it can be easily adjusted and put into place as best as possible using crowbars or metal pipes using them as leverage.

After laying the slabs in place, they begin to seal the joints and places of mounting loops with cement or concrete mortar.

The design of the slabs itself is designed in such a way that there are longitudinal voids inside it, which play the role of thermal insulation. But if the roof structure has an attic space, then the slabs should still be covered with a layer of insulating material.

Just as in the previous case, roofing felt, roofing felt or bitumen mastic in order to protect the insulating material from the penetration of condensate and water vapor.

Any building ends with a roof, which is its highest point. The roof protects the building from precipitation, sun rays, winds and frosts, in other words, provides much-needed comfort inside the building. This means that the roof must be stable and strong in order to successfully withstand gusts of wind and rain, protect against solar radiation, retain heat and be impervious to dampness. Thus, the roof protects buildings from destruction occurring as a result of atmospheric influences: moisture, freezing and thawing.

Video on how to build a floor using wooden beams

Concrete roofs are generally flat surfaces. Such roofs are economical, reliable and durable, and also have a long service life. Such garage roofs are made from monolithic casting or ready-made reinforced concrete slabs, which require appropriate coating in the future. Read the instructions on how to cover a garage roof with bicrost.

What to cover with?

When asked what is the best way to cover garage roof made of concrete slabs, quite recently the answer was quite obvious - roofing felt. Since the technology for installing roofing felt sheets involves the use of mastic or roofing felt, the work is not very safe, and is also labor- and time-consuming. Currently, new and improved roofing materials with improved characteristics, accordingly the use of roofing felt began to fade into the background.

A modern analogue of roofing felt is Bikrost, which refers to soft roofing roll type. Installation process of this material much simpler, here you only need to use gas burner for melting the adhesive layer, as well as a roller, a roofing mop and a primer, which is applied to work surface roofs before laying Bikrost. If we compare Birkost with roofing felt, the former is more flexible and has an increased service life.

The process of laying Bikrost on concrete and reinforced concrete roof consists of several stages:

Cleaning and leveling the working base;
Application of a special primer for better adhesion of Bikrost to the roof surface;
After the primer has completely dried, Bikrost is directly laid, which is rolled out across the surface across the slope of the roof;
Overlaps at the ends must be at least 15 cm, and at the edges at least 10 cm;
A gas burner is necessary to heat the Bikrost base, and then use a roller to roll out the material, gluing it to the roof surface.

How to make a concrete screed?

Installation concrete screed for a garage roof is a rather complicated and time-consuming process, but it's worth it. Such a roof has excellent waterproofing properties and also eliminates deformation that may be caused by the load from large quantity snow.

The phasing of work must be strictly observed:

At the level of the top of the garage walls, floors are constructed from metal or wooden guides, which are laid horizontally. Further along long walls and the floor elements are attached on top of the guides. Their length should be approximately 15 centimeters longer than the length of the garage on each side.
Then the boards are laid end-to-end on the ceiling and additionally secured with guides with external parties garage walls.
Sheets of roofing material are laid on top of the ceiling with an overlap of 10-15 cm to ensure good waterproofing.
Insulation in the form of mineral wool or expanded clay is laid on top of the waterproofing.
After laying the insulation, a screed made of a solution of cement and fine sand is applied on top.
The screed is poured slowly, filling all voids and cracks. The surface of the screed is leveled using a wooden strip.
The screed dries within a few days; only after complete drying is another layer of waterproofing and finishing coat applied.

How to pour concrete?

Look at the view clear example how to fill a garage roof with concrete:

You can cover a concrete garage roof without a burner with roofing felt or waterproofing. Soft roof roll type is excellent option for covering concrete roof. In addition, you can use liquid rubber, which is in Lately is very popular. Read the guide on how to calculate the foundation for a garage.

An excellent roof for a concrete or expanded clay concrete garage roof base would be Bikrost or Corrugated Sheet.

The ceiling for a garage roof made of foam concrete is usually made of a single slope. In addition, this roof option is the most common among garage construction.