How the inversion roof is built: the technology of the device of the inversion roofing system

Installing shingles isn’t the only step in building a roof. There are many uses for different kinds of roofs, and the inversion roof is one of the more interesting styles. This ground-breaking system actually turns the conventional roofing methodology on its head. The inversion roof positions insulation above the waterproofing layer rather than between the roof deck and the interior. By regulating temperature swings, this technique not only shields the building from the elements but also improves energy efficiency.

An inversion roof’s technology requires careful planning and exact implementation. First, a thick layer of waterproofing is applied to the structural roof deck. The main barrier against precipitation, snow, and other environmental factors is this layer. A layer of carefully positioned thermal insulation sits above this waterproofing membrane. By protecting the structure from temperature extremes, this insulation lowers the cost of heating and cooling by keeping the building warmer in the winter and colder in the summer.

The efficient management of moisture is one of the key elements of the inversion roof system. Any moisture that seeps through the roofing material is kept from entering the building structure by putting the insulation above the waterproofing layer. This design extends the life of the roof and the building it protects by reducing the possibility of mold, mildew, and structural damage.

An inversion roof also needs to be built with expert craftsmanship and meticulous attention to detail. To guarantee performance and durability, every layer—from the structural deck to the last protective covering—is painstakingly put in place. In addition to improving the building’s structural integrity, this technique gives property managers and homeowners piece of mind because they know their investment is well-protected.

The specifics of the inversion roofing system

Violating the layers’ customary placement is the constructive core of the inversion. In the typical pie, the capture of household evaporation is laid beneath a vapor barrier beneath the first’s soft roof. Next is a heater that has a waterproof covering covering it from the elements.

Destructive atmospheric attacks always affect the bitumen, polymer, or bitumen-polymer continuous rolled carpet that serves as the standard roof’s external waterproofing layer. No one has been able to completely resolve this issue up to this point, despite manufacturers’ wishes to give these kinds of coatings resistance to climate negatives.

However, the inversion scheme—that is, the reversal of the roofing layers—appears, shifting the waterproofing to the center of the pie. According to inversion technology, the insulation covers the waterproofing layer, which is technically replaced by the external coating. The ballast is then piled on top of both structural elements.

One component of the inversion roofing system that is required is ballast. It shields the waterproofing and insulation from sunlight, which gradually and steadily causes the building materials to become inappropriate. It serves as both a decorative element that elevates the external picture and a stabilizing element that keeps the underlying layers from shifting.

It was feasible to avoid using mechanical fasteners throughout the flat roof thanks to the application of ballast. The quantity of ceiling holes that pose a possible—and occasionally actual—risk of leaks has been steadily decreased. Only the areas adjacent to load-bearing walls, parapets, and roofing passages are fastened, as demonstrated by the installation rate, which was very positively reflected.

In the case of the inversion design, there is no vapor barrier per se. The waterproofing layer that has been installed in its customary location effectively fulfills its functional duties. The cost of constructing a flat roof with a "reverse" pie is further decreased and the device’s speed is noticeably increased as a result of the rejection of steam protection.

The benefits of the inversion scheme are summed up as follows:

  • Increased wear resistance. Especially in areas with expressively aggressive climatic conditions in relation to building materials.
  • Reduced cost. Savings are based on a reduction in the materials used and the processes of their laying.
  • Environmental Safety. The components of the roof pie are in contact with the environment that do not violate the natural balance and do not release volatile toxins.

For the installation of operated sites, such as terraces, cafes, lawns, and summer gardens with shrub plants, inversion systems are perfect. When building "green roofs," the opposite strategy is employed. Fertile soil containing plants serves as the ballast, and once the non-explosive structures are put in place, their surfaces are covered in washed gravel or pebbles with sizes ranging from 20 to 40 mm.

By folding the weight of the roof pie’s constituent parts—snow and wind—the load on the nonexplosive roof is computed. When a flat roof is in use, the total weight of all the loads mentioned above, along with the weight of summer furniture and visitors, is used to determine the load on the supporting structures.

The following are some of the inversion system’s drawbacks, which somewhat overshadow its long list of benefits:

  • Impressive weight. The mass of the ballast distributed per square is depending on the number of storeys of the building and the type of wind load 50 – 90 kg/m². Before the construction, it is often necessary to strengthen the supporting structures of the house or obviously built taking into account considerable cargo.
  • Repair complications. It is difficult to find the cause of the leakage under ballast, it is very difficult to eliminate. Moreover, before the repair, it is necessary to remove a solid amount of load from the roof section, then return it to its place.
  • The complexity of the process. In order to move ballast to the roof, it takes a lot of labor efforts or rental construction equipment.

The device’s structural configuration is limited. The inversion roof type that is both operated and unexplored can only be constructed on flat roofs that have parapets. Water collection trays, funnels, and a slope to the values are necessary in order to remove precipitation from the surface. The maximum bias of 3% will be roughly 1.7–1.8º in the stops that are familiar to inexperienced observers.

Various techniques are used to form slopes based on the roof’s intended use. Expanded clay is backfilled into the operated structures, and a reinforced screed is layered on top. On underutilized roofs, the slopes are made using inexpensive, non-commercial techniques, such as the installation of metal structures with flat slate leveling sheets or wedge-shaped thermal insulation plates.

Because the foundational element’s bearing capacity is insufficient, inversion roofs are not constructed using profiled steel sheets.

"A specialized roofing system intended to improve thermal insulation and provide weather protection is required when building an inversion roof. By inverting the conventional roof structure, this cutting-edge technology adds insulation on top of a waterproof membrane. This special configuration not only minimizes heat loss through the roof to maximize energy efficiency, but it also assures durability against severe weather. Gaining an understanding of how an inversion roof is constructed entails knowing how to strategically place insulation and layer materials to achieve maximum performance and longevity."

The main components of the inversion roof

Both non-standard materials and standard layouts for flat structures are employed in the construction of inversion roofs. One typical instance is ballast that isn’t utilized elsewhere. In the reverse scheme, we will examine the roofing cake components in the order that they are utilized throughout the structure.

First of all, we observe that the inversion system’s device can be based on railway slabs that are ribbed, hollow, and continuous. This can complicate the ceiling. Other options include monolithic concrete, prefabricated leveling structures, and all varieties of reinforced cement screeds that are at least 5 cm thick and are filled with a solution with a stuky strength of 150.

Similar to traditional soft flat roofs, the geotextile layout schemes involve separation layers of geotextiles, and the device in question involves polymer rolled coatings and an estrian insulation. Their role is to stop polymer modifiers from being "tugged" by substances that have a comparable effect, like bitumen coatings.

Preventing thin polymer carpets from deforming and breaking when they come into contact with rough surfaces is the second crucial function of the dividing layers.

The device of the waterproofing carpet

The number of layers in the inversion roof’s waterproofing component is determined by the anticipated operational load:

  • In one layer. Arrange unexplosive systems, the waterproofing of which is performed by a polymer membrane with PVC or EPDM labeling. The first of these types of polymer coating has practically no restrictions. The second will be allowed to use roofs up to 2 m wide without roofing, where it can be laid with a single canvas without cutting and welding.
  • In two layers. Arrange operated systems, the waterproofing of which is first performed by a bitumen carpet, freely laid on the base. A second layer created by a bituminous or bitumen-polymer roller coating is fused on top of the waterproofing on top of the waterproofing. T.e. The layers are fused with each other, but not recorded on the basis.

When one layer of a polymer membrane is used for waterproofing, the base is almost always covered with a dividing layer made of thermally treated geotextiles.

Material Disassium exceeding 300 g/m³. It is required for both bitumen roof laying and rough surface laying, such as railway plates and screeds, as a lining layer and a barrier against the diffusion of modifying substances.

Strips with overlap that measure at least 5 cm along the side edges and 10 cm along the end cover geotextiles. The separator’s stripes are fused together in a single appointment by means of a hot air weld. When drilling, geotextile fibers—which have a unique record due to heat treatment—are not wound on mechanical fastening components.

Similar to the geotexer, the polymer membrane is welded in two doses, i.e., but laid in stripes. Every joint’s inner and outer seams are cooked. The carpet is secured with a mechanical fastener with a step up to 33 cm along the adjacent lines to parapets, walls of neighboring buildings, chimneys, and other roofing. A small section should have at least four fastening points surrounding its passageways.

After the fasteners by the waterproofing layer’s parapet section were installed, all of the polymer carpet’s adjacent vertical walls were closed, featuring elegant details or vertical surfaces measuring at least 12 cm. Thus, make sure that the fastening points are waterproof and have decorative camouflage. An extra waterproofing strip, 30 cm wide, is glued to the lines of the conjugation of vertical and horizontal structures so that it fits on both adjacent planes.

In order to build a waterproof carpet with two layers, a propane burner will be required. With its assistance, bitumen-polymeric and rolled bitumen carpets are laid out. The burner is only used to weld individual stripes together into a single panel; the first layer is not melted on the basic base.

Only the areas of overlap on vertical surfaces receive feeds for the bitumen inversion system’s lower layer. They are positioned along the lines of conjugation of horizontal and vertical building structures in the shape of a side, with a height of 12 to 15 cm. It is necessary to account for these allowances for all vertical conjugation when cutting and joining the bands into a single carpet. Inversion roofs do not use scrolls.

In situations where the device cannot be removed from the waterproofing carpet’s edge, a self-adhesive or readily fushed bitumen-polymer material is utilized. Applying a mica, gravel, or shale sprinkle to its exterior will shield it from the sun.

A completely assembled lower layer receives the melted upper portion of the two-layer waterproofing. In the event that a cold roof’s "green" ballast is to be built, bitumen-polymeric materials free of roots are used to arrange the second layer. For instance, they make use of technoelast-grain, which offers two levels of defense against root damage. It is fitted with polyethylene that has been thickened and added to chemical additives.

From above, the two varieties of waterproofing carpets overlap. A thick geotextile that grinds needles and weighs between 350 and 400 g/m 2 shields the bitumen carpet. Polymer waterproofing is covered with a divisive material that has a fiberglass base weighing 100 g/m 2 or a polyester base weighing 70 g/m 2. The purpose of this layer is to set the groundwork for installing thermal insulation.

Features of thermal insulation

This layer is a part of the insulated inversion roof device. If it wasn’t planned, ballast is just covered with small pebbles or well-rounded gravel on top of the separation layer. Summer houses and cottages with green roofs are constructed without insulation. In these situations, the waterproofing cornation consists of just spreading rich soil and planting vegetation.

The insulated inversion roof has a far more intricate plan. The material with the lowest water absorption can be used as a heater because the thermal insulation layer is essentially unprotected from atmospheric water. Simultaneously, there are other fairly heavy components of the roofing pie, so the thermal insulation layer does not have the right to significantly add to the weight of the structure.

The ability of roofing thermal insulation to maintain its technical properties under conditions of continuous water contact is a crucial feature. Therefore, extrusion polystyrene foam is regarded as the best option. Water cannot possibly seep through the slab’s thickness and inside his sealed cells. Furthermore, the material retains air from the cells and does not release heat.

Slabs with milling grooves to facilitate installation are used in the roof insulation system device. The individual thermal calculation is used to determine the thickness of the heat insulation. Polistyle stoves are installed in one or two layers, based on the results of heat engineering calculations specific to a given area.

Ballast and options for its application

The thermal insulation of the inversion system is covered with a diffusion polypropylene geotextile that has a weight passport indicating a minimum of ±150 g/m² as specified in the technical passport. This is the next layer of lining that acts as a barrier against air moisture and pollutants while also shielding the insulation from mechanical damage.

Condensate that has accumulated in the insulation’s thickness is allowed to fly out freely through the polypropylene protective layer. She keeps water and dust out of her interior, though. It stops water from penetrating the insulation plates’ butt joints and damaging them, as well as the waterproofing from crystallizing moisture, which swells up when it freezes.

As is customary, polypropylene material is laid in single carpets with stripes that overlap by 10 cm and are joined by a single stage of welding, which results in a single seam rather than two parallel welding lines.

Anticorneal material is applied on top if there is a chance that seeds may germinate and cause plants to grow. This stops roots from penetrating the waterproofing and extending into the overlap. This is accomplished by installing "green" roofs as well as flat roof structures with ballast composed of gravel or pebbles.

Flat inversion roofs are constructed using a variety of ballast types, including:

  • Gravel and pebbles. Poured with a layer of at least 5 cm on top of the rot of bitumen waterproofing on unexplosed roofs.
  • Paving slabs. Piece coating with a thickness of at least 4 cm. Installed using the stands adjustable in height with a polymer bearing plane or support. Used only in operated varieties.
  • Concrete floating screed. Collected from the railway plate or poured in the form of a constructive layer with a thickness of 5 cm over a waterproofing or separation layer so that it does not contact with the base and adjacent structures. Used on operated roofs with the proposed transport load.
  • Plant soil. Depending on the bearing capacity of the construction, the permissible load and the selected type of plants, fertile land is laid on the drainage membrane with a layer of 4 to 20 cm. Arrange on unexploited and combined, t.e. partially operated roofs.

The components of the roof pie are held in place by a uniform layer of gravel and pebble ballast that is applied throughout the equipped area. To stop the insulation from surging, its weight is slightly increased in yendov and around the funnels.

Slabs of pavement are placed on roofs intended to support pedestrian traffic. It is aligned in a zero horizon, making it convenient and safe to move around thanks to adjustable devices. Gravel, pebbles, or granite gravel are frequently used as filtering materials to fill the spaces between the coating lined with tiles so that rainwater can drain into the internal drainage system without getting in the way.

Over the insulation’s separation layer, the concrete screed is poured. Condensate removal from the thermal insulation layer requires the floating kind. Two-level funnels are installed for the same reason, enabling the collection of condensation moisture and rainwater from beneath the screed.

A drainage layer made of a profiled polymer membrane is required for the green roof, which uses the soil-growing layer as ballast. In the event of insufficient precipitation, the drainage layer is essential for both the removal of excess moisture and its maintenance. Soil is placed on top of the membrane, followed by a geotextile carpet that has been fused together using heated air.

Compost, expanded clay or perlite, vermiculite, and brick chips make up the fertile layer. This type of substrate drains excess water much more effectively than regular garden soil and is far easier to work with.

The plant species listed below are suitable for natural landscaping:

  • Lawns. Including ready -made roll lawns. Can be supplemented with wildflowers. The easiest and most prompt way to form a green lawn. However, it requires periodic additional watering and haircuts.
  • Seduma. Plants of natural alpine lawns, unpretentious and well tolerating excessive solar radiation. They practically do not require care.
  • Mosses. The least suitable option is the option, from ancient times used in the decoration of roofs with Scandinavians. In addition to unpretentiousness and decorative qualities, mosses can increase the thermal insulation qualities of the structure.

Small bushes can be supplemented with a list of plants with a small root system, if the supporting structures permit it.

The Inversion Roof Building Technology
An inversion roof is designed to prevent damage and extend the lifespan of the roof. The system involves placing insulation on top of the waterproofing layer.
This setup protects against temperature fluctuations and UV radiation. It also helps in maintaining the membrane"s integrity over time.

With regard to controlling temperature variations and safeguarding the building structure, the inversion roofing system is a cutting-edge method of roofing. The inversion roof provides effective protection against thermal stress and moisture penetration to the building by reversing the usual layer arrangement of waterproofing and insulation.

The layered structure of an inversion roof is essential to its construction. Thermal insulation is first applied to a solid substrate, usually concrete or metal decking. Thanks to its ability to stop heat gain or loss through the roof, this insulation is essential for sustaining steady interior temperatures.

A waterproofing membrane is installed over the insulation. This membrane acts as the main defense against water intrusion, keeping the underlying structure dry and free from damage caused by moisture. It is made to resist environmental factors and UV rays, extending the life of the roof.

To ensure its effectiveness, an inversion roof must be constructed with great care and attention to detail. To keep the waterproofing layer intact, joints, seams, and penetrations must be installed correctly. Sufficient drainage systems are also included to effectively divert any water buildup away from the roof’s surface.

All things considered, the inversion roofing system is a progressive approach to contemporary building techniques. It prolongs the life of buildings and improves energy efficiency and environmental sustainability by optimizing thermal performance and waterproofing capabilities.

Video on the topic

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Denis Shcherbakov

Professional roofer with 20 years of experience. I know everything about the installation, repair and maintenance of various types of roofs. I will be happy to share my knowledge and experience with you.

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