How to insulate a flat roof: thermal insulation methods and technical rules of work

For buildings to remain comfortable and energy-efficient, flat roof insulation is essential. Whether you’re building a new roof or remodeling an old one, selecting the appropriate insulation technique is essential to getting the best thermal performance. This article examines a variety of insulation methods and the fundamental rules for carrying them out successfully.

Insulation is one area where flat roofs differ from pitched roofs in their challenges. These roofs can result in significant wintertime heat loss and excessive summertime heat gain if they are not properly insulated. In addition to controlling indoor temperature, good insulation gradually lowers utility bills and uses less energy.

There exist multiple techniques for insulating flat roofs, each with specific benefits contingent on variables such as financial constraints, local climate, and roof configuration. The selection of insulation type should take into account elements like thermal resistance (R-value), moisture resistance, and ease of installation. Traditional materials like fiberglass and mineral wool can be replaced by more contemporary options like spray foam and rigid foam boards.

Following best practices and technical regulations is crucial before beginning any insulation work. By following these guidelines, you can be sure that the insulation meets building codes and operates at its best. In addition to improving thermal efficiency, proper installation methods increase the roof structure’s longevity and durability.

The nuances of thermal insulation of the flat roof

The principles of thermal insulation for pitched roofs are different from those for warming flat roofs, and specific guidelines must be followed. The roof pie’s layering order is the only possible analogy. The thermal insulation layer is conveniently positioned among the elements of flat structures, which lack rafter systems.

Nothing is fastened to the crate to create a ventilation gap for the components’ airflow. Partial gluing of the coating to the underlying basis results in the creation of peculiar idiots instead of ventilation channels, if necessary.

Construction customs dictate that the flat roof’s roofing pie is assembled by consistently hooking its components onto one another. Among the customary elements are:

  • Vapor barrier. Plays the role of an obstacle in the way of everyday fumes. Located from residential, household and t.P. premises.
  • Thermal insulation. Prevents the passage of heat waves from the inside out and in the opposite direction. At the same time copes with the duties of the barrier for sound vibrations.
  • Waterproofing. Covers thermal insulation from the outside, protecting it from atmospheric water. It is covered in 4-6 rows depending on the size of the roof slopes directing water to the water intakes, and on the technical characteristics of the roofing material. The outer layer of waterproofing of a conventional roof serves as a finish coating. During the construction of ballast roofs, gravel, soil-lowering layer, paving slabs, etc. are laid on top of the waterproofing.

When layers are not positioned in the proper order or laying regulations are broken, the owners are left with terrible results and must pay hefty repair or replacement costs.

Keep in mind that the designated layers and the styling order they follow are only employed when absolutely required to keep the heat generated by heating the space.

Insulation is not necessary for the roof of the summer kitchen or barn used to store inventory. In these cases, the roofing pie consists of a prefabricated screed and waterproofing if the basis is corrugated board, or just waterproofing if it is arranged on a concrete basis.

Classification of insulated flat roofs

When building a roof over private property, skilled craftsmen may become deeply confused by the apparent simplicity of a flat roof. People will be taken aback when they realize that the budget option is a flat roof.

It will be extremely reasonably priced and function flawlessly if the roof is constructed with the right number of waterproofing layers, a heater that is the necessary thickness, parapets, drains, and its heating.

The following types of flat roofs are affected by the insulation:

  • Combined, They are also unraveled. Their roofing structure is combined with ceiling overlap. Insulation is carried out by laying thermal insulation with related layers on top of the base. The plus of combined systems is that they practically do not need winter cleaning from snow cover. After all, the overlap is regularly heated from the inside. Minor snow deposits without problems are eliminated by the natural power of the wind, in view of which such roofs are recommended not to be equipped not by parapets, but by lattice fences. Disadvantage: the condition of the roof is difficult to monitor. The slightest damage is to be reflected in leaks with the subsequent serious restoration of the roof pie.
  • Attic, having two subspecies within the category. The attic overlap of the first subspecies is supplemented by light superstructure on top. It is clear that the ceiling overlap should be isolated in such cases. In the diagram of the second subspecies, attic superstructure and overlap are independent structures. So, insulation is permissible for both of them. The plus of attic structures is to freely monitor the state of the roof and in the timely detection of brewing leaks. The owners can dry the roofing cake with banal ventilation of the attic. Among the significant advantages is the possibility of insulation upon completion of the construction of the roof. The disadvantage lies in an impressive value, which, however, pays off due to long -term operation and rare repairs.

According to the second category of attic roofing systems, thermal insulation may be found above the floor or inside the superstructure. The second option for installing insulation on a flat roof is, nevertheless, more important.

The second plan calls for the formation of an air chamber between the thermal insulation system and the roofing. This attic divides the building into two sections, each with a distinct background temperature.

The temperature differential between the attic roof’s exterior and interior will not be as great as it is in homes without an attic. The temperature differential won’t be as drastic and damaging. plus the minimal amount of condensation, which is the key to attic roof longevity.

Analysis of technical nuances

The choice of insulation for a flat roof depends on a number of factors, including the building owner’s financial situation, the specifications for thermal insulation, and the construction’s load bearing capacity.

The majority of materials used to insulate walls and ceilings are expanded clay, light concrete, and slabs made of both synthetic and mineral materials. But now at the top of the list of preferred choices for flat roof insulation is:

  • Foam polystyrene – hard material obtained by pressing and sintering of the granules of Stirol. Light, sufficiently strong slabs are used as a layer, on top of which a screed is filled.
  • Extruse polystyrene foam – hard material obtained by mixing stylistic granules with a foaming substance with the assistance of high temperature and pressure. Everything is kneaded and brought to condition in the extruder, and then squeezed out of it with simultaneous molding in the plates of standard dimensions. It is used as the basis for the device of the finish roof and as a heat -insulating layer for a concrete screed.
  • Mineral wool – fibrous semi -rigid and hard material obtained as a result of the melting of silicate rocks, metallurgical production waste or their mixtures. Depending on the density, it is used as the basis for the waterproofing device or as the component of the multilayer insulation system.

Representatives of polystyrene draw granules with a closed granule structure and little moisture absorption. The previous representative’s extrusion namesake has the lowest thermal conductivity. Mineral wool is comfortable to lay on. The lightest weight, resistance to burning, and stability of insulating properties are the benefits of all these choices.

The disadvantage of raising mineral wool is that the process of insulating it from the outside with its flat roof must align with the dry spell. The installation of thermal insulation must be finished on the first day of work, with no portion of the work being transferred to the following day. Since the material will no longer have the insulating qualities specified by the manufacturer, mineral wool will need to be altered entirely.

According to protocol SP 02.13130.2009, which regulates measures to ensure the fire resistance of the object under construction, the type of insulation appropriate for arrangement is chosen. The collection of rules on thermal protection of SNiP structures 23-02-2003 is followed in calculating the thickness of the heat insulation.

Producers of thermal insulation for roofing materials offer a variety of materials with varying density parameters, thickness, and compression strength. With products sold to the construction industry, you can set up an insulation system that meets the requirements in any design scenario.

These materials are also used to create wedge-shaped heat-insulating plates, which are used to organize the natural flow of atmospheric water to drainage objects. Installed along the lines of conjugation between vertical planes and a horizontal roof surface, the five-tens are released.

Filters stop water from standing still and forming puddles in the parapets next to walls, in the square with regard to chimneys, anti-aircraft lamps, etc. It is important to keep in mind that wedge-shaped thermal insulation is not a suitable substitute for the insulation layer. The water disposal problems are the only ones that need to be resolved.

The choice of the method of insulation depending on the base

Insulated roofing systems are installed either on a reinforced concrete foundation or on a profiled steel sheet. Prefabricated screeds, reinforced flooded, and slabs are used in railroads. Only concrete bases and foundations with adequate strength characteristics are used for the cement-sand screed pouring process.

Depending on the type of base, the insulation system installation method and the specifications of the necessary thermal insulation are chosen:

  • Roof insulation with the base from the railway slabs is carried out using mineral wool, covered on top of the national team or cement-sandy reinforced screed. The strength of the compression of the insulation material should be from 40 kPa and from above. Deformation parameters of at least 10%. With the device of a two -layer insulation system, the strength of the compression of the lower tier should be at least 30 kPa, the upper tier from 60 kPa.
  • Thermal insulation of the repaired flat roof is performed in two layers. The lower layer is folded from plates with compression resistance indicators from 30 kPa, similar data from the upper layer from 60 kPa if the deformation changes are possible not more than 10%.
  • The insulated roof on the corrugated board must have a two -layer structure. The strength indicators of the lower tier laid on the tops of the corrugated sheet should be from 30 kPa, the same data laid on top of the layer from 60 kPa. Deformation limit 10%. If the device is planned on top of the bitumen-polymer roof, the material is laid directly on the thermal insulation system.

Thermal insulation from a flat slate or CSP can be laid on a galvanized corrugated board without the need for a preparatory leveling stratum as long as the plate’s thickness is twice that of the space between the corrugations. The profiled sheet’s flat portion, which has at least 30% of its own area, is what the insulation must rely on.

For insulated flat roofs, mechanical fasteners are installed at a rate of two pieces per stove. The coating and insulation are fixed at the same time if the roof is constructed on a concrete foundation.

The frequency of fastener installations increases along the lines of conjugation with vertical surfaces, around chimneys, and along other passes. According to profiled flooring, the waterproofing coating is fixed separately from the insulation of flat structures.

Rules for laying insulation

Since the insulation makes up the largest and most noticeable portion of the volume, the rules governing the roof pie device are closely tied to the principles of installing thermal insulation on flat roofs. Recall that thermal insulation materials can be laid on top of a cement-sand screed or act as a foundation for waterproofing in conjunction with finish coatings.

The surface is level for the installation of lighthouses that gauge the power of the heat-insulating system for the screed installation when pouring on top of the solution.

The details of the flat roof’s thermal insulation are as follows:

  • The laying of heat -insulating plates begins with an angle located in a low roof area. If the structure of the structure was not observed during the construction process, then the first elements should be timed to the place of installation of water intake funnels or gutter.
  • On a profiled flooring, the heater slabs are put so that their long side is perpendicular to the corrugation to install fasteners in different ridges.
  • When placing multi -layer thermal insulation, the slabs are placed according to the principle of running seams. T.e. The location of the plates in each layer should resemble brickwork. In addition, the butt lines and crossroads of the upper tier should not coincide with the analogues of the lower row. For this, thermal insulation plates of the second tier are cut in the order proposed by the manufacturer.

The cutting technique, which has been tried and tested numerous times, can drastically lower consumption.

Options for fastening heat -insulating plates

Slab insulation is fixed in accordance with the different types of roofs that are constructed. The thermal insulation layer is fixed to the flat roof using the following techniques:

  • Mechanical. Fixation is carried out by the so -called telescopic fastener, the elements of which consist of screwing into the base of self -tapping screws with plastic fungi passing through the thickness of the roof pie. Special anchors are clogged into concrete slabs, with screws with plastic sleeves are attached to the screeds.
  • Glue. Thermal insulation and other components of the roof pie are glued to hot bitumen-polymer mastic. The insulation is glued evenly, with the base it is obliged to contact at least 30% of its area. The device of roofing systems with bitumen or bitumen-polymer coating is not used in a rainy weather period, t.To. completely deprives the insulation of the opportunity to part with excess steam. It is possible to glue at any time of the year if the cake is completed by a roof membrane that passes out the excess of fumes accumulated in thermal insulation.
  • Ballast. The insulation laid on a flat roof is simply covered with a waterproofing carpet, on top of which the gravel-heaters are filled up or paving slabs are installed on plastic supports. The components of the system are free, fasten the pie only around the perimeter and around the roofing passes.

Green roofs are becoming increasingly popular as ballast roofs. It is true that these are inverse systems because the pie’s layering order deviates slightly from custom. Waterproofing is covered with insulation, which also serves as a vapor barrier.

A geodrenate polymer membrane—which is made especially for roofs with landscaping—overlaps the thermal insulation. The soil-lowering layer is positioned on top of the drainage layer.

Thermal insulation device from the inside

It is physically inconvenient to lay insulation slabs from the inside of a building with a flat roof. Not everyone is able to continue working with their hands extended upward.

However, it is useful since you can work in any weather—rain, snow, wind, or scorching sun included. Additionally, it is not required to complete all thermal insulation tasks in a single day, t.To. Nothing will get wet on the material.

Install thermal insulation starting with the inner stem and working your way outward:

  • A bar, both or one of the sides of which is equal to the thickness of the insulation plate, we screw the ceiling and walls along the line. For the installation of internal insulation, wood -breeds and polystyrene foam plates are suitable, which hold the shape perfectly.
  • We install a similar bar from the bar against the opposite wall.
  • Glue the polystyrene plate on the hot bitumen mastic or glue to the ceiling and the side of one of the strips. Tightly press the insulation to the mating surfaces. We fill the conditional strip with the insulation slabs completely. If necessary, cut the extreme plates in factual sizes.
  • We screw the bar on the side of the heat -insulating strip created by us, tightly pressing it to the mating elements.
  • Clutching polystyrene foam, we form again and glue the insulation strip.
  • We alternate the screwing of bars with gluing thermal insulation until we fill the ceiling plane.
  • We fasten the stapler to the bars with a plastic film and sheathe the ceiling with drywall or similar material.

Prior to installing thermal insulation within the building, the location, size, and height of the electrical lighting appliances must be planned for.

Improving your building’s comfort and energy efficiency requires proper insulation of your flat roof. You can make sure that your roof offers the most thermal protection possible by using the right techniques and abiding by technical specifications. Start by selecting the best insulation material for your needs and budget, whether that be spray foam, fiberglass, or rigid foam boards.

Make sure you properly prepare the roof surface before beginning installation. To guarantee that the insulation adheres properly and functions at its best, this also entails cleaning and fixing any damage. Sealing joints and crevices is important because these are common places where heat can escape and undermine your insulation efforts.

Another important consideration is proper ventilation. It keeps moisture from accumulating, which could harm the roof.

It is imperative to comprehend appropriate thermal insulation techniques and adhere to technical guidelines in order to properly insulate a flat roof. You can greatly improve energy efficiency and comfort by selecting the right insulation materials and installation techniques for your climate and building type. In order to provide long-lasting and efficient insulation, this article addresses practical methods like spray foam insulation and the installation of rigid foam boards. It also emphasizes important factors like ventilation and moisture control. Gaining an understanding of these fundamentals enables both contractors and homeowners to develop sustainable and energy-efficient flat roof solutions.

Video on the topic

Insulation of flat roofs #construction #monolith

Sprayed insulation

Installation of insulation on a flat roof.How to properly lay thermal insulation?

What do you think, which element is the most important for a reliable and durable roof?
Share to friends
Alexandra Fedorova

Journalist, author of articles on construction and repair. I will help you understand the complex issues related to the choice and installation of the roof.

Rate author
Add a comment