Repair of a flat roof using rolled materials, sequence of work. Repair of used roof

Flat roofing is the most common type of roof arrangement. However, it also has a limited service life. The Atelier Roofing company provides a wide range of roof carpet maintenance services, including current and major repairs flat roof in Moscow and Moscow region at a competitive price.

Types of repairs

• In the case of a local nature of the work, partial replacement of the defective coating is carried out, as well as the elimination of peelings and swellings.
• When overhauling a flat roof, it is assumed that the insulating layer and carpet material are completely replaced, including preparing the surface for the subsequent installation of a new covering. Reason overhaul there may be more than 40% damage total area roofing covering. Due to high labor and material costs this type works are much more expensive than the current one.

What does the cost depend on?

Repair begins with a specialist visiting for inspection. current state flat roof and assessment of the necessary labor and material costs. After this, the terms and estimated cost of materials and other consumables are agreed upon with the customer.

The final price for flat roof repairs is formed from the following cost items:

• costs for the purchase of basic and draft materials;
• fare;
• waste of time for craftsmen.

The final estimate is drawn up only after a thorough inspection of the flat roof, selection of an effective technical solution to the customer’s problem and taking into account all third-party factors.

How we are working

Leave a request on the website or by phone

IN certain time meet our specialist

We agree on technical details

We conclude a contract with a guarantee

We carry out installation work within the approved time frame!

Ready! You accept and pay for the work

When is repair needed?

Problems with roof covering flat type, as a rule, arise due to water stagnation on the surface, wetting of the thermal insulation layer or evaporation of moisture from the roofing carpet. For the reasons described, the following damage to the coating may occur:

• surface swelling;
• delamination of the roofing pie;
• formation of depressions and funnels with rainwater;
• formation of bubbles or cracks;
• germination of various vegetation through the inner layers;
• destruction of the coating around chimneys.

A periodic preventive inspection will help you limit yourself exclusively to routine local repairs. Otherwise, after some time you will have to not only completely replace the coating, but also spend money on restoration of the premises. It is recommended to carry out work only on warm days and in dry weather.

Our services

To repair a flat roof of proper quality, our specialists carry out all work according to a specific plan:

• a specialist visits the site;
• the coating is inspected, all necessary measurements are taken and the required calculations are performed;
• if necessary, the old coating is dismantled;
• a project for the future roof is being prepared;
• installation of the base and roofing material is carried out;
• are carried out final works for drainage installation.

The coatings used for flat roofs have a long service life. However, most roll and membrane materials have to be changed before the stated service life has expired. This is largely due to the occurrence of various types of damage that form on the roof during its operational life.

Types of roofing damage

The main reason for damage to roofing carpet is poor quality installation work and the use of cheap materials, the quality of which does not correspond to current operating conditions. Lack of regular maintenance also leads to both minor and critical damage that requires immediate repair.

The most common types of flat roof damage include the following:

In order to prevent the condition of the roof covering, it is recommended to conduct a routine inspection of the front surface of the roof. If problems are discovered, a decision must be made on how to proceed with repairs to prevent further damage.

Flat roof repair methods

Depending on the type of defects and the area affected by the damage, restoration and repair work on flat roofs is usually divided into the following groups:

• current repairs are local work performed when minor defects and damage are detected in the roofing system. Basically, the damaged roof covering is partially replaced, peeling and swelling are eliminated;
• major repair - is a complete replacement of the current insulating layer and roofing material, including a full preparation cycle work surface for further installation of a new coating.

The basis for major repairs is the presence of damage of various nature on more than 40% of the total flat roof area. Unlike local work, major repairs require the investment of a significant amount, which is comparable, and in most cases exceeds the cost of laying a new roofing cover.

What material to use for repairs

The technology for installing and repairing flat roofs involves the use of various materials. The use of a particular material is determined by the current condition of the roof and the coating that was laid or applied previously.

Major repairs of a flat roof are carried out in all cases when more than 40% of the total roof area is damaged

In general, the following technologies are used to repair flat roofs:

• repair with screed - used in cases where concrete slab the ceiling is severely damaged and a full-fledged thermal insulation pie is required. In this case, a vapor barrier membrane, mineral or foam insulation, fine-grained expanded clay, concrete mortar, primer and insulating coating. To mix the solution, it is recommended to use sand concrete M300, produced under trademarks"Polygran", "Master Harz" and BESTO;
• repair using roll coverings - used for restoration of flat roofs of various configurations. Various analogues of roofing felt or PVC membrane are used as roll coverings. Among the bitumen roll coatings, one can note the products of the TechnoNIKOL corporation under the brands Stekloizol KhPP-2.5, Technoelast KhPP and Uniflex EPP. As a roofing polymer membrane, it is better to use a coating under the Ecoplast V-RP or Logicroof V-RP trademark. To work with roofing felt derivatives, you must have a gas burner, and to lay PVC membranes - adhesive composition And construction hair dryer;
• repair using liquid rubber- most often performed when servicing multi-story residential buildings, since the applied material is light in weight and does not weigh down the floor slab. For use, we can recommend waterproofing under the brand name “Technoprok R”, Euromast Plus and Tremproof 250. Liquid rubber is applied using a special industrial sprayer. In addition to the insulating material, vapor barrier is used, thermal insulation coating and deviation.

When repairing a roof with a screed, it should be taken into account that to mix a sufficient volume of concrete you will need a concrete mixer and a large number of containers for transferring concrete mixture. To distribute concrete, it is necessary to set linear guides. Leveling the solution is done using a steel rule.

In order to understand in more detail the technology of working with various materials, we will consider the process of repairing each type of flat roof separately. A more general technology describing the process of current and major repairs will be discussed below.

Repair of roll roofs

Roll coatings under the trademarks Stekloizol KhPP-2.5, Tekhnoelast KhPP and Uniflex EPP, which were mentioned above, are modern bitumen roll materials. For their production, a binder composition based on bitumen and filler is used, which is applied to fiberglass on both sides. Asbagal is used as a protective front layer - a coarse-grained coating applied to a special polymer film.

TechnoNIKOL Corporation produces a large assortment roll bitumen coatings for roofing

As a rule, Stekloizol, Tekhnoelast and other bitumen roll coatings are used to protect flat roofs with preliminary installation of a concrete screed. The main problems of this coating are the formation of local damage in the form of cuts and cracks that occur as a result of improper use of the roof. If the operating technology is violated, air and water bubbles may form.

To eliminate local defects, patch repair is used, when the damaged area is completely covered with a new canvas. The size of the patch directly depends on the area of ​​damage.

Repair of cracks, breaks and other surface damage is carried out as follows:

If it is necessary to eliminate swelling and bubbles on the surface of the rolled coating that arise due to seasonal temperature fluctuations, then it is necessary to carefully cut the damage crosswise.

Next, you need to bend the corners of the coating so that you can dry the inner surface. After drying, the surface is cleaned and treated with bitumen mastic, and the bent edges are pressed back. Then patch repairs are performed using the technology described above.

Repair of membrane roofs

PVC membranes are a specialized waterproofing coating designed to protect roofs and concrete foundations. The extrusion method is used in the production of membranes. This ensures that the final material will have zero water absorption.

Mechanical damage and depressurization of seams are two main problems that arise during improper use of a flat membrane roof. For example, when removing snow carefully with an iron shovel.

A special welding machine is used to lay the PVC roofing membrane

To repair mechanical damage, you will need to perform the following work:

1. The damaged area of ​​the membrane fabric is cleaned and treated with an organic solvent.
2. A patch is cut out of a single membrane sheet, the size of which will cover the gap or other damage on the surface of the roofing carpet by 5–10 cm.
3. The patch is laid on the prepared area of ​​the roof and soldered using a welding machine. While heating, the patch is gradually smoothed with a roller.

Depressurization of seams occurs due to a violation of the technology for laying PVC membranes. As a rule, the membrane is poorly heated or placed “under tension” to hide irregularities.

To repair, you will need to treat the inner surface of the peeled seams with a solvent. If necessary, they should be cleaned using available means. Next, the seams are soldered with a welding machine. If the length of the peeled seam exceeds 5–7 m, then it is additionally taped with Eternbond repair tape.

Video: installing a patch on a membrane roof

Repair of mastic roofs

Liquid rubber, unlike bitumen roll coatings and roofing membranes, allows you to create a seamless roofing carpet. This is especially true for flat roofs of old buildings, where preliminary installation of a concrete screed is impossible due to the load it places on the load-bearing elements of the building.

Liquid rubber for roofing is a two-component composition that is mixed before application to the surface.

The main damage to a mastic roof is cracks that occur during long-term use of the roof. To repair them, liquid rubber of a similar composition to that previously applied is used. For example, liquid rubber “Slavyanka” for roofing is a two-component composition that is applied using a unit high pressure and spray nozzle.

The technology of roof repair using liquid rubber is a combination of the following operations:

If there is extensive damage to the roof surface, then first of all it is necessary to eliminate local holes in the roof. After the restored areas have dried, a second layer with a thickness of 3–4 mm is applied. If necessary, laying fiberglass and arranging a finishing layer of liquid rubber.

Video: spraying liquid rubber on the roof

How to make an estimate correctly

Before carrying out any repair work, you should calculate its cost. To do this, you will need to draw up an estimate in electronic or paper form. This will avoid shortages or overspending. building materials necessary for carrying out repair work. Especially if major renovations are planned.

If there are swellings in the roofing covering, a cross-shaped incision is made with further processing of the damaged area

In order to create an estimate, you must complete the following steps:

• measure the working surface - using a tape measure and other tools, measure and inspect the working surface. Based on the data obtained, the total surface area in need of repair is calculated;
• calculate the quantity and cost of consumables - based on the current condition of the flat roof, the type of repair that is planned to be carried out is selected. Taking this into account, consumables and tools necessary to carry out this work are selected;
• calculate the roofing covering - according to measurements and technical condition, the covering will be selected to be used for repairs. Based on this, its quantity and cost are calculated;
• draw up a work plan - at this stage it is necessary to think about how the material will be delivered to the site and the sequence in which repair activities will be carried out;
• adjust the amount of consumables - the previously obtained volume of consumables must be increased by 15 to 20%. This will allow you to make a reserve for errors in cutting and accidental damage during repair work;
• choose a construction store - prices are monitored in construction markets and in stores represented in your region. If possible, you can contact the store directly with your estimate. The costs of delivery and unloading of the material should be added to the final cost.

If repair work will be carried out by qualified workers, then the corresponding item should be included in the estimate. It is not recommended to purchase specialized tools for performing work for personal use. It is more rational to rent it. Especially if a major overhaul is planned in compliance with technology.

Current flat roof repairs

Routine repair of a flat roof includes work aimed at eliminating local damage in the form of cuts, breaks, cracks and blisters. In essence, these works allow you to quickly eliminate local damage without affecting entire sections of the roof.

Mainly current repairs are carried out in case of damage soft roof, for the construction of which bitumen or membrane coatings were used. You can perform routine repairs yourself without turning to specialists - you will need a minimum of tools.

For installing a soft roof, a bitumen-based roll material called “Stekloizol” is most often used.

As an example, we can consider the technology of current repairs for various local damages. To carry out the work you will need bitumen waterproofing material (glass insulation, euroroofing felt, bikrost), gas or gasoline blow torch, sharp knife, rolling roller, cold bitumen mastic.

The general technology for repairing extensive damage to the surface of a flat roof is as follows:

1. The damaged area is thoroughly cleaned of fine-grained dust. The cleaning area should be 10–15 cm larger than the damaged area. For this, use any convenient brush with metal bristles.
2. Using a sharp knife, a square or rectangular piece of insulating material containing the defect is cut out. The canvas is removed right up to the ceiling.

   During local repairs, damaged roofing material is cut out using a special tool

3. The prepared area is cleaned with a stiff brush. After this, the hole is left to dry. To speed up the process, you can use a hair dryer.
4. Based on the cut fabric, patches are prepared from a new roll coating. The number of patches must strictly correspond to the number of cut layers.
5. Bitumen mastic is applied to the cleaned and dried area. Used for application convenient spatula or an old brush with hard bristles. The mastic is maintained according to the instructions.

   During routine repairs, the damaged area is replaced with a new patch made of similar roofing material

6. The first patch is glued to the mastic. Care should be taken to ensure that the canvas lays flat, without forming folds or waves. A rolling roller is used for smoothing.
7. Using a similar technology, mastic is applied and the remaining patches are glued. After gluing the last sheet, you will need to cut out an overlapping patch, the size of which should be 15 cm larger than the cut out area.
8. On final stage an even layer of mastic is applied, onto which an overlapping sheet of insulating material is glued. A roller is also used for smoothing.

When using roll coatings with a welded surface, the installation technology is similar to that described above, with the exception that installation of the patch will require a construction hair dryer. The working surface of the cut patch is heated with a hairdryer until the bitumen layer becomes soft. Then the canvas is carefully laid over the gap and ironed with a roller.

The technology for eliminating cracks and minor damage to the canvas (15–20 cm) is similar - the damaged area is cleaned of protective coating, after which mastic is applied and a covering patch is glued. In this case, there is no need to cut out the damaged fabric.

Video: Installing a Fused Patch

Major flat roof repairs

Major repairs, as specified in the section above, are advisable to carry out when damage and defects are present on more than 40% of the total area of ​​the flat roof.

The essence of a major overhaul is to completely replace the current roofing material. If necessary, a complete replacement of the roofing pie can be carried out, including steam and thermal insulation, as well as screed.

Dismantling of the roof covering is carried out using special equipment

As an example, consider a major repair of a flat roof with further installation of a weld-on roll coating. To complete the work you will need a seam cutter, a chipper, a concrete mixer, a gas burner, a shovel, laser level, metal rule.

The overhaul technology consists of the following:

1. The damaged roll covering, PVC membrane or liquid rubber is completely dismantled. For this, a grinder, a wall chaser and a sharp ax with a metal handle are used.
2. The working surface is cleaned using stiff brushes, shovels and grinding machines. The removed roofing felt is cut into small sheets and then stored in a separate place. Where possible, the dismantled material is transported to a landfill.

   After dismantling, the old roofing covering must be taken to a specialized landfill

3. Produced visual inspection working surface, during which its technical condition is determined. If the surface is represented by a concrete screed, then in most cases it must be dismantled.
4. The concrete screed is being dismantled. For this concrete surface marked using a seam cutter. To remove the concrete layer, special bumpers are used.
5. Cleaning in progress construction waste and preparing the roof surface for pouring concrete screed. Shovels, brooms and other equipment are used for this. After cleaning, the surface is wetted with water.
6. Linear guides are being installed. For this purpose, special steel beacons are used, which are mounted on dowels or cement-sand mixture. During installation, a slope (3–5%) is maintained from the center to the edges of the roof or vice versa.

   The roof screed is carried out along pre-arranged guides

7. A concrete mixture based on M300 cement is being prepared. If possible, it is better to use ready-made dry mixtures from the manufacturer. As reinforcement, so as not to weigh down the concrete floor slab, microfiber is used, which is added to the solution during mixing.
8. The concrete screed is being poured. To do this, the mixture is supplied in portions starting from the center of the roof. A steel or wooden rule is used for distribution. During work, the screed is checked by level to ensure that the required slope is maintained.
9. After pouring and spreading, the concrete screed is covered with polyethylene. In this condition, the roof surface must be moistened with water 2-3 times a day for 7 days. Full time drying of the concrete layer - 28 days.
10. After 2 weeks from the moment of pouring, the linear guides can be dismantled. The resulting voids are cleaned and rubbed over with a concrete mixture of similar composition.

    Laying a roll or membrane covering is carried out only after the concrete screed has completely dried

11. After the screed has dried, the surface is cleaned of abrasive particles. After this, the vapor barrier is laid diffusion membrane. The vapor barrier is laid with an overlap of 10–15 cm relative to the adjacent row.
12. Thermal insulation material is laid in the form of mineral or basalt slabs. If you plan to install a serviceable roof, it is recommended to lay wool in slabs with a density of at least 50 kg/m3.

    Insulation made of mineral or basalt wool is laid on the concrete screed

13. Thermal insulation boards are laid end to end. If necessary, the second layer is laid staggered so that the joints of the first layer do not coincide with the joints of the second.
14. A thin-layer concrete screed (3–4 cm) with fiberglass is poured. The preparation and pouring technology was described above (see paragraph 8). After the second layer of concrete screed has dried, they begin laying the roofing.
15. 2–3 layers of lining roll material are laid. To do this, the canvas is carefully rolled out as the working surface is heated using a propane or gasoline torch.

    A gas or gasoline burner is used to lay the welded roof covering.

16. The roofing material, like the lining material, is installed in a staggered manner with an overlap on the sides of the roof. If a roll coating is used, which is laid on mastic, then the surface is first lubricated with a primer, and only then the material is laid.

At the final stage, roof aerators, gutters, junctions, cornices and other accessories and devices are installed.

It is worth keeping in mind that major repairs of a flat roof in each case may have certain features. This is largely due to the operational condition of the roof, previously laid waterproofing material, etc. But in general, any major repair consists of dismantling work, cleaning and preparing the old surface, laying underlying and roofing material.

Video: laying roofing on a flat roof

Flat roof storm drain repair

Drainage system of private or apartment building designed and calculated long before the construction of the house. When constructing private buildings (garages, one-story houses), as a rule, external organized drainage is used. During the construction of multi-apartment high-rise buildings, internal drainage is designed and constructed.

Before repairing the roof of private buildings, it is recommended to perform preliminary dismantling of the storm drainage system. After repairs, the storm drain is reinstalled. If repairs are required, then during installation, damaged funnels, gutters, brackets and other products are replaced with new ones.

The roof funnel is installed during the installation of the roofing pie

Repair of the internal storm drain is carried out in the following sequence:

1. The internal channel is cleaned using a flexible cable with a nozzle in the form of a metal brush.
2. At the stage of installing linear guides for the screed, a slope is formed towards the technological hole in the roof structure.
3. After the concrete screed has dried, a roof funnel is installed in technological hole for cement mortar.
4. After the installation solution has dried, the surface near the funnel is treated with a bitumen primer.
5. Next, roll waterproofing is laid in 2 layers. After this, the crimp ring is mounted and a hole is cut in the funnel.

Features of flat roof repair in winter

Routine and major repairs of flat roofs in winter are carried out only in exceptional cases when repair work is necessary to maintain the integrity of the ceiling.

Laying roll coverings in winter period should be carried out with extreme caution

When carrying out work in winter, you must adhere to the following rules:

• It is advisable to carry out repair work on a clear day - this will avoid problems when laying roofing material;
• when laying materials, moisture should not be allowed to get between the different layers of the roofing cake;
• If the winter is snowy, then frame-tent shelters are used for repairs, which help prevent precipitation from getting on the roof surface.

To ensure thermal conditions, gasoline or gas are used heat guns. Roofing material must be maintained at room temperature within 24–36 hours.

How much does it cost to repair a flat roof?

Flat roof repair is complex works, therefore, their final cost consists of the cost of the material, the cost of its delivery, labor costs, etc. At the same time, the cost of major repairs is difficult to estimate without a preliminary inspection of the flat roof.

On average, the cost of current repairs, which you can do yourself, will cost no more than 200 rubles/m2. The total costs mainly consist of the cost of the material and the rental of tools if they are not available. Major work costs approximately 2–2.5 times more than local repairs of minor damage. If repairs are carried out with the involvement of specialists, then the final cost increases by about 2 times.

To estimate the cost of repairing a flat roof, you can use the table below. The data in the table is compiled based on price lists from three specialized companies performing repairs in the central region of Russia.

Table: Cost of Repairing an Existing Flat Roof

Name of works	Unit change	Price (work + materials), rub./m2	Price (work only), rub./m2
Repair of an existing flat roof made of fused materials
Roof repair in 1 layer, including repair of old roofing carpet (opening and gluing of swellings and other defective places)	m 2	500	350
Roof repair in 2 layers, including repair of old roofing carpet (opening and gluing of swellings and other defective places)	m 2	800	530
Roof repair in 2 layers, including complete removal of the old roofing carpet and screed repair	m 2	900	560
Installation of a flat roof during capital construction and repairs
Installation of roof covering in 2 layers on the finished base	m 2	750	430
Installation of a new lightweight roof (vapor barrier, 150 mm mineral wool insulation, 2 layers of fused material)	m 2	1700	570
Device new roof(vapor barrier, 150 mm mineral wool insulation, reinforced cement-sand screed, 2 layers of welded material)	m 2	2400	800
Installation of a new roof with a screed and slope (vapor barrier, mineral wool insulation 150 mm, expanded clay slope with an average thickness of 100 mm, reinforced cement-sand screed, 2 layers of fused material)	m 2	2700	910
Repair of existing flat roof made of polymer membranes
Repair old roof using a PVC membrane covering (removing bubbles on old carpet, laying geotextiles, installing a 1.2 mm membrane covering)	m 2	850	350
Installation of a roofing carpet made of PVC membrane on a finished base with mechanical fastening	m 2	750	250
Installation of a new lightweight roof (vapor barrier, insulation with 150 mm thick mineral wool slabs, installation of a roofing carpet made of 1.2 mm PVC membrane)	m 2	1750	420
Installation of a new roof with a screed and slope (vapor barrier, insulation with mineral wool slabs 150 mm thick, expanded clay slope, cement-sand screed up to 50 mm thick, installation of a roofing carpet made of 1.2 mm PVC membrane)	m 2	3000	1000

Major roof repairs are expensive work, the quality of which determines the comfort and coziness inside the living quarters of the house. Therefore, when constructing a house, you should perform all the work efficiently and not skimp on materials. In order not to bring the roof to a critical condition, it is recommended to carry out routine inspections and local repairs, if the need arises.

Any coverings, including roofing ones, do not last forever. Even the most modern of them are subject to wear and tear and the gradual loss of their protective qualities. Under the influence of precipitation, temperature changes, mechanical factors, the roofing material is destroyed, cracks, bubbles, peelings, breaks, etc. appear on it. And here it’s just a stone’s throw away from leaks! Flat roofs are especially prone to such damage due to their geometry and the use of soft materials as coverings.

Moreover, the first minor defects may appear literally after a couple of years of operation. So, should we re-cover the roof? Not at all. Damage can be eliminated by performing timely flat roof repairs. Simple measures to restore the roofing will help extend its service life, and, importantly, will not require large expenses.

• surface cracking;
• local mechanical damage (holes, through cracks, cuts);
• peeling of the roof covering along the edges and in the seams;
• the appearance of folds;
• rotting of the coating;
• swelling, blisters;
• wear (loss) of the top layer of the roofing carpet.

The causes of defects are various factors: errors during installation, insufficient insulation of attic floors, mechanical stress, environmental influences.

In any case, damage to the integrity of the roof will sooner or later lead to leaks and destruction concrete floors. This necessitates the need for ongoing local repairs of flat roofs at a time when its complete replacement is not yet necessary.

Repair of rolled bitumen roofs

Most often, flat roofs are covered with roofing felt or its analogues from a series of built-up bitumen waterproofing materials (euroroofing felt, rubemast, glass insulation, etc.). So let's start with them.

Local damage (cuts, breaks, penetrations)

Mechanical damage to the roof surface can occur as a result of its clearing of snow in winter, hail, or human movement. Other possible reasons: deformation of the base and initial defects during installation of the coating.

Local defects are eliminated by installing a patch on the damaged area. The patch is cut from the same material as the main covering. Its edges are rounded to reduce the likelihood of detachment, and the size is made to cover the defect by 10-15 cm in all directions.

Traditional repair algorithm:

• the damaged area is cleaned (including from the protective coating) and dried;
• cut out the patch;
• glue it onto mastic or fuse it using a hair dryer;
• smooth the patch with a roller or other suitable object to align the edges of the patch with the main surface.

If everything is done correctly, the integrity of the roof will be completely restored, and the patch will be almost invisible.

The process of installing a patch over a crack in a bitumen coating is filmed on video:

Extensive damage to the bitumen roof

It occurs most often if moisture seeps under the bitumen layer, a large area of ​​the roof is damaged and begins to rot. To restore the integrity of the coating, perform the following actions:

• the damaged area is cleared of gravel (if there is a sprinkle);
• cut out a square or rectangular piece of fabric containing the damage (layer by layer);
• clean and dry the formed hole;
• using a cut piece of canvas as a template, cut out as many patches from the bituminous material as the number of layers it was decided to replace;
• spread mastic on the exposed area and glue the patch end-to-end, smooth it with a roller;
• glue the next layers of patches in the same way;
• cut out another finishing patch so that it covers the damaged area by 10-15 cm on all sides;
• spread the mastic and glue the patch onto it, smooth it with a roller.

When using a weld-on material, repairs are carried out in the same way, with the exception of the use of bitumen mastics for gluing the patches. The patch cut from the waterproofing is heated from below with a hot air gun until the adhesive bitumen layer melts. After which the patch is placed in place, fixed and smoothed with a roller.

Cracking of bitumen surface

Bituminous materials are susceptible to the formation of small surface cracks caused by exposure to the sun and high temperatures.

To seal surface cracks, do the following:

• the damaged area is cleaned of dirt, old mastic and coating (if any);
• dried;
• cover with mastic in 2 layers;
• fall asleep renovated area coarse sprinkles.

It is also possible to apply a patch made of the same material as the main coating to the area with a network of cracks. In this case, its size should cover the area of ​​the defect by 10-15 cm on all sides. The patch is glued on top of the mastic; when choosing a fusing method, the lower side of the patch is preheated with a jet of a hot air gun.

Air or water bubbles

They are formed as a result of seasonal or daily temperature fluctuations in the summer, when the roof quickly cools and warms up. The air in the insulating layers of the roofing carpet expands and “inflates” bubbles. The same thing happens if moisture seeps into the under-roof space. When heated, it evaporates, forming swellings.

Repair work to eliminate bubbles:

• remove layers of topping from the swelling area;
• the place of swelling is cut lengthwise with a knife or an envelope (crosswise), the edges are folded back to dry parts;
• dry the inner surface;
• clean it from contaminants;
• treat the cavity with bitumen mastic;
• glue the bent edges back onto the mastic, press and roll the restored canvas with a roller;
• a pre-prepared patch is glued with mastic or fused to the cut site, overlapping it by at least 10-15 cm, and pressed with a roller.

More details:

Peeling of the waterproofing carpet from the base

It occurs if, during the installation of the rolled sheet, the base (concrete slab or screed) was not sufficiently cleaned of dust and dirt. Or the installation was carried out without priming the base with a bitumen primer. All this leads to a low degree of adhesion between the waterproofing material and the base.

To eliminate the described problem:

• the exfoliated part of the canvas from below is cleaned of mastic;
• remove dirt from the base and dry it;
• apply mastic to the base and glue the peeled section onto it;
• press the restored area with a roller;
• if the material sheet at the place of delamination has been torn, then a patch with a width of 20 cm is applied along the tear line.

Repair of membrane roofs

Polymer membranes are a material more durable than any bitumen waterproofing. Their service life reaches 50 years. But even membrane roofs are not insured against various types of mechanical damage, including punctures, ruptures, and depressurization of seams. Most often, coatings are damaged when performing various tasks on the roof, for example, when clearing snow or installing equipment.

Restoring a damaged membrane usually involves sealing defects with polymer patches, and if the seams diverge, resoldering them.

Mechanical damage

Tears and cracks on the surface of the polymer sheet can occur as a result of careless movement on the roof, clearing snow and ice using sharp tools, falling objects or dragging them.

Sequence of restoration work:

• the repaired section of the canvas is cleaned and degreased;
• cut out a patch from the membrane, preferably of the same type and manufacturer as the main coating; its dimensions should be such as to cover the defect by 5-10 cm on each side;
• the patch is soldered with a stream of hot air using a welding machine;
• roll the sealed area with a roller.

The whole technology looks like this:

When installing a patch on an EPDM membrane, you can use glue method fastenings, without the use of welding.

Depressurization of seams

Separation of adjacent fabrics at seam joints occurs when wrong choice blowing force and welding temperature during installation, speed of the welding machine. Other possible reason– installation of the membrane with an initial “tension”, with the help of which inept installers visually compensate for unevenness of the base.

Depressurization is eliminated as follows:

• the place of delamination is treated with a special cleaner;
• the seams are soldered using a welding machine;
• in some cases, to strengthen the areas of delamination, a membrane patch is applied over the problematic seam.

There is another way to get rid of damage without using welders and expensive components. This is about modern technologies Eternabond, used to restore the tightness of seams and minor damage.

Repair material Eternabond is a rolled tape with an adhesive layer applied on one side. The tape is capable of forming a homogeneous surface with the membrane, which is not inferior in strength to a solid fabric.

Repair work using EternaBond tape is performed as follows:

• the surface of the defect is treated with a special solvent;
• cut off the necessary part from the roll of tape;
• remove the protective film from the adhesive side of the tape;
• Press the tape to the defect site and roll it with a roller.

More details:

Repair of mastic roofs

Flat roofs are not always covered with rolled materials or polymer sheets; quite often in recent years they have been used for these purposes. liquid waterproofing. A special mastic is applied to the base of the roof, which, under the influence of air, hardens and takes the form of a polymer membrane.

After several years of use, cracks may appear on the mastic roof. They should be cleaned of dust and dirt, and then filled flush with mastic or polymer-cement mortar. An additional continuous layer of mastic is laid if the area of ​​damage is more than 40%. In this case, the damaged areas are first restored locally with mastic, and then another layer of mastic with a thickness of at least 3-4 mm is applied over the entire surface, and after it has hardened, a protective layer is applied.

Features of a major overhaul

All measures for partial restoration of the roof relate to current (planned) repairs, during which only minor damage can be eliminated. If the service life of the coating is coming to an end, and defects account for more than 50% of its area, a major repair of the flat roof is carried out.

It consists of replacing the entire roofing covering, and, if necessary, all components of the roofing pie (thermal insulation, vapor barrier).

The range of work carried out during major roof repairs:

• the old coating is dismantled;
• if the base was a cement-sand screed, then, in most cases, it is also removed - using seam cutters and bumpers;
• all layers that make up the roofing pie are inspected (insulation, waterproofing membranes, vapor barrier films);
• if damage is detected, the problematic layer is replaced;
• a new cement-sand screed is poured (if it was originally provided);
• New roof covering is being laid.

In addition, major repairs may include replacement or installation of roof aerators, installation drainage funnels, arrangement of junctions and eaves overhangs.

When performing major roof repairs, it is possible to completely reconstruct it. For example, by including a layer of insulation in the design, a conventional roof can be converted into an insulated one. Or, by adding a durable top layer, you can turn an unused roof into a usable one.

During reconstruction, some materials may be replaced with others that are more suitable for specific operating conditions. A common situation: replacing a bitumen coating with a polymer membrane. In this case, it is not necessary to dismantle the old material. PVC membranes mounted on a bitumen roof through geotextiles, which act as a separating layer. If TPO or EPDM membranes are used, then they are laid without geotextiles, directly on the bitumen coating.

Major repairs are an expensive undertaking, in most cases complicated by the dismantling of the old coating. Therefore, you should not bring the roof to a deplorable state before its service life has expired. And for this it is necessary to periodically carry out preventive inspections of the roof and, if defects are detected, carry out timely maintenance.

1. The photo above shows standard design, the so-called ⇒ built-up roofing. Here as waterproofing coating Roll bitumen materials are used.
2. When installing such a roof, a gas burner with a propane cylinder is used, as well as a hose with a reducer to adjust the outlet pressure. When laying on a new base, apply two layers; if the old one is well prepared, then you can get by with one layer.
3. To increase waterproofing properties and service life, slopes are installed on flat roofs. It is needed in order to control the flow of rainwater, creating high points on the parapet areas towards the drainage funnels.
4. Initially, the slope must be designed relative to the funnels and create zones with a rise, slopes with a height greater than the main roof area. By following these instructions and the design drawings, it will be possible to prevent the appearance of stagnant zones where water will accumulate.
5. Large puddles on the roof are a good environment for the appearance of vegetation, and with the slightest defect in the joint seams, a layer of water will eventually push the moisture into roofing pie which will lead to a major overhaul.

Roofing defects such as swellings, air bumps on the surface appear due to insufficient drying cement-sand screed grounds. The same defect can occur even after repair, if you do not dry the damaged area by opening the cake and immediately fuse new layers onto the old ones.

Installing aerators over the entire roof area will create exit points (ventilation) and remove moisture vapor from the under-roof space.

• A slope can be created using a screed with the addition of expanded clay, and the specified slope is formed metal profile or stone blocks cut along a cord from a high point to a low point.
• The slope can also be formed from wedge-shaped insulation from the TechnoNIKOL company from solid (dense) stone wool, then coat it with a primer based on bitumen mastic. This allows you to create an adhesive substrate for durable installation soft roof.
• To maintain the correct geometry and dimensions of overlaps along the side and end connections of adjacent rolls, it is necessary to first spread the bitumen coating and cut according to the shape of the junction of half-timbers, weather vanes, parapets, chimney and ventilation pipes.
• Next, when working with a gas burner, you need to heat the material to a temperature sufficient to connect the materials to molecular level. An indicator on the underside of the rolled material helps with this; when a burning flame is directed towards it, the film is deformed.
• The characteristic leakage of the bitumen roller ahead of the movement of the equipment with the roll is a sure sign of compliance with the technology of “welding” the coating.

Problems of flat roof reconstruction

Reconstruction of flat roofs of industrial and civil buildings on site Russian Federation this is one of the most common and natural species construction work. Despite the emergence of modern roofing materials, the obvious improvement in work culture when installing built-up waterproofing is enormous cash are spent annually on current and major repairs of roofs of this type. Leaks, swellings, folds, cracks and other defects in the roofing carpet lead to a significant increase in the cost of operating buildings.
As part of routine roof repairs, which is carried out either when the first signs of a roof leak appear, or based on the results of assessing the condition of the roof, one or two layers of rolled fused materials are applied. The durability of such repairs, as a rule, is short - only 2 - 4 years and it is necessary to re-apply the next layers of roof waterproofing. As a result of such constant repairs, the roof waterproofing carpet can have a thickness of more than 200 mm (see Fig. 1.)

Fig.1. Waterproofing carpet of a flat roof after numerous repairs.

One of the main reasons for such a short service life of roofs is the saturation of various roof elements with water, both during the direct installation of the roof and during their subsequent operation. Excess moisture appears in roof elements when work is carried out in the autumn-winter period, during precipitation; roof elements also become wet when the roofing carpet is damaged, or in the absence or violation of the continuity of the vapor barrier membrane. When water or water vapor gets inside the roofing pie structures, the thermal insulation layer of the roof, laid under the layer of rolled waterproofing, gets wet. This is also facilitated by the construction solutions that are most popular today. Backfill is widely used expanded clay gravel, thermal insulation of roofs with fibrous mineral wool boards with high water absorption. These materials can become saturated with water during the construction process or during precipitation; and during operation, when various kinds damage to the roofing carpet. It should be noted here that insulation materials with high water absorption are prone to water accumulation under the waterproofing layer. In this case, water may concentrate not in the place of leakage through the waterproofing, which makes it much more difficult to find the location of damage to the roof. When heating the roof due to solar energy(in summer up to 85 degrees C), moisture from the heat-insulating layer evaporates creating excess pressure under waterproofing membrane and, as a consequence of this, swelling, bubbles, and separation of the roofing carpet occur. (see Fig. 1). These damages form subsequent violations of the waterproofing layer, leading to water leaks. Roof repair, which consists of re-sticking waterproofing, is not effective insofar as it does not eliminate the cause of roof defects, which is the increased water content of the roof’s thermal insulation layer.

Existing options for reconstruction of flat roofs

The situation can only be radically corrected by a decision to overhaul the roof, in which the entire roofing pie is dismantled. But a major roof repair is a complex of expensive construction work, including a large amount of financial investment in dismantling and removal of construction waste. In addition, during major roof repairs there is a risk of causing significant financial damage. interior decoration and building equipment, since in the event of precipitation when the roofing waterproofing It is possible that water will get inside the building.
To some extent, it is possible to find a solution to this problem by installing so-called “breathing” roofs. In this case, in the lower layer of the waterproofing carpet, due to its partial fastening to the base, a network of channels is created through which the subsequent release of excess pressure under the waterproofing membrane occurs. This solution has several significant disadvantages:

• High complexity of installation of roof elements. Difficult-to-execute units for extracting the steam-air mixture.
• If the roof is damaged in one place, moisture through the system of under-roof channels spreads over the surface of the entire roof. In this case, it is almost impossible to find the location of the leak; often it is necessary to dismantle the entire roofing carpet.
• When installing a breathable roof over an old waterproofing carpet, areas of stagnant water, which almost always occur on old roofs, are not eliminated. Especially with increased thickness of the waterproofing carpet.

Fig.2. Section of a flat roof after a conventional reconstruction (applying a new waterproofing carpet).

1. The base of the roof is usually a reinforced concrete slab.
2. Vapor barrier layer.
3. A layer of old thermal insulation dampened due to leaks ( mineral wool, polystyrene foam, expanded clay, lightweight concrete, etc.)
4. Migration path of the steam-air mixture in the heat-insulating layer when the roof is heated.

6. Excess pressure created by migrating water vapor.
7. Blisters on the surface of the new roofing carpet laid during roof reconstruction.

Buffer layers of a flat roof made of monolithic foam concrete.

An effective solution for the reconstruction of flat roofs is the use of monolithic. In this case, foam concrete screeds are placed on the surface of the old waterproofing carpet. Next, a new roofing carpet is fused onto the surface of the foam concrete screed. The complete technology for reconstructing flat roofs consists of a series of following stages.
. Assessing the condition of a flat roof: identifying areas of stagnant water, the presence of damage to the roofing carpet, etc.;
. Preparing the base for installing a buffer foam concrete screed. Cutting off folds, peelings, bubbles - to the base, removing debris, loose coating, removing air cavities;
. Acceptance of hidden work;
. Installation of buffer foam concrete screeds with a thickness of 40 - 100 mm;
. If necessary, the installation of vertical transitions (fillets) also from monolithic foam concrete;
. Prime the base with bituminous primers, according to the recommendations of the roof waterproofing coating supplier;
. Installation of a roofing waterproofing carpet in two layers;
. Installation of roofing fans (wind vanes) at the rate of 1 piece per 150 - 200 sq. m.;

Fig.3. Section of a flat roof during reconstruction using monolithic foam concrete.

1. Base - reinforced concrete slab.
2. Vapor barrier.
3. Old thermal insulation layer.
4. Paths of migration of the steam-air mixture in the thermal insulation layer of the roof.
5. Damage to the old waterproofing carpet.
6. Distribution of migrating water vapor in the pore space of the foam concrete layer.
7. A layer of new waterproofing laid during reconstruction.

With this roof construction, the layer serves as a buffer space for water vapor. High blood pressure, created by water evaporating from the heat-insulating layer of the roof, is evenly distributed within the vast pore space of the foam concrete, without leading to damage to the roofing waterproofing carpet. It is this effect that explains why layers of rolled waterproofing on foam concrete roofs lie without repair for more than ten years with a complete absence of swelling and other damage. A similar mechanism has the effect of frost resistance. cellular concrete- only when freezing, not steam is squeezed into the pore space of foam concrete, but ice crystals grow without damaging the material itself.
A separate line should be noted about the effect that we called “self-drying” of foam concrete. Physicochemical binding of water during hardening of Portland cement with hydrate new formations ensures a decrease in the water content of non-autoclaved foam concrete even inside hermetically sealed spaces. This occurs when laying monolithic foam concrete in buffer heat-insulating screeds, well masonry, and filling other building cavities with non-autoclaved foam concrete. When water is absorbed, the hardening processes of foam concrete are intensified, thus, when drying, foam concrete increases its strength characteristics. It is well known that long-term hardening is possible cement concrete in general, and cement foam concrete in particular. This allows the foam concrete screed, even with subsequent ingress of water as a result of damage to the waterproofing coating, to dry on its own during the hydration of the cement matrix of the foam concrete. It should be noted that the practice of working with monolithic foam concrete when installing flat roofs convincingly shows that in roofs using non-autoclaved foam concrete, a vapor barrier layer is not necessary. This can also be explained by the “self-drying” effect.

Description of the properties of monolithic foam concrete and equipment for its production.

The production of foam concrete mixture was carried out by us using the so-called one-stage technology for the production of foam concrete mixture. This eliminates the preliminary preparation of two-phase foam (F - D). The equipment prepared three-phase foam (L-T-G) in one stage; the foam generator and pump for supplying the foam concrete mixture over a distance are excluded from the technological chain. When producing foam concrete mixtures on a construction site, the fundamental requirement is the minimum required set of equipment. A foam generator is a device that requires a high level of work culture during operation; its presence significantly complicates the technology for producing foam concrete. At the same time, the presence of a foam generator does not provide any tangible advantages in the production of monolithic foam concrete. The foam concrete mixture was supplied by injecting pressure into the working chamber of the foam concrete mixer. This method allows you to abandon the use of pumps (gerotor, peristaltic) when transporting foam concrete, with a supply height of the foam concrete mixture of up to 30 meters. Thus, the production and supply of monolithic foam concrete was carried out by one unit - a foam concrete mixer, combining the functions of a foam generator, foam concrete mixer and pump.

Rice. 4. Equipment for the production and supply of foam concrete mixture is located on the body truck. Most of the workplace is occupied by a warehouse of binders and fillers.

Rice. 5. The production of foam concrete mixture is carried out by one plasterer worker. In the foreground is an SPBU-500M foam concrete mixer and a container for mixing water.

Since the requirements economic efficiency Repair of flat roofs requires the installation of buffer foam concrete screeds minimum thickness, then this imposes a number of special requirements on the physical and mechanical properties of foam concrete. It is mandatory that the foam concrete contains a complex modifying additive, which contains water-retaining additives. Otherwise, it is impossible to ensure a guaranteed strength gain, especially in summer with intense heating of the base for pouring foam concrete. Thin-layer laying requires mandatory volumetric reinforcement to prevent the development of shrinkage deformations. Volumetric mesh reinforcement of the cement matrix of foam concrete is carried out with hydraulically active silicate fibers. As part of a complex additive, it is desirable to use additives with a water-reducing effect. Sometimes it is necessary to use additives that accelerate the setting and hardening of the foam concrete mixture. The selection of a complex additive should be carried out by a construction laboratory, taking into account the fact that many types of modifying additives have a pronounced defoaming effect, for example, naphthalene-formaldehyde type superplasticizers.

Table 1 Physical and mechanical properties of foam concrete.

Foam concrete grade according to medium density	Compressive strength, MPa	Thermal conductivity coefficient, W/m*deg.	Thermal resistance layer of foam concrete 100 mm thick.	Weight 1 sq.m. layer of foam concrete 100 mm thick. (including operating humidity), kg	Notes
					Used only as thermal insulation material and also for filling cavities
					Can be used as a base for soft roof stickers

Based on the results of many years of work related to the reconstruction of flat roofs using buffer foam concrete screeds, the following positive effects of this design and this material can be identified:
1. The service life without repairs increases to 10-20 years.
2. Laying of monolithic foam concrete is carried out using industrial methods; a team of two people can lay up to 700 meters of square foam concrete screeds per shift.
3. Foam concrete screeds provide additional thermal insulation of the roof. See Table 1.
4. When laying monolithic foam concrete screeds, roof unevenness is eliminated and there are no places where water stagnates.
5. The technology for gluing roll bitumen materials is simple and is no different from the technology for gluing these materials onto ordinary cement-sand mortar.

Rice. 6. The photograph shows one of the stages of reconstruction of a flat roof using monolithic non-autoclaved foam concrete.

You see a foam concrete screed lying on an old waterproofing carpet. The next and final stage of the work is the installation of a waterproofing carpet made of bitumen fused materials on top of the foam concrete screed.

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