Typical waterproofing of structural joints at roofing works conducted with Abrin materials

There are two types of roofs: non-operated and operated. The first ones are common roofs on which only workers climb for construction, repair and cleaning works. The second type includes the roofs of industrial and civil buildings and erections where, in addition to roof maintenance, it is stipulated that people constantly come to the roof for locating and checking up/repairing various equipment.

Operated and non-operated roofs have various intended uses that is why their roofing pies can consist of various materials. Despite this fact, the roof should be elastic to prevent deformations under thermal, moisture action and due to the support mechanical deformation.

At the design and reconstruction of a roofing pie special attention should be paid to an upper waterproofing layer, and this particular layer is the protection for the main roofing pie and is exposed to aggressive environmental factors action. Should this layer be damaged, all other roof space is also damaged, starting from heat insulation, which cannot perform its function anymore, and finishing with the destruction of the support (floor slab panel) which will lead to expensive repair.

Various purposes roofs have one structural element that is similar in terms of its installation complexity and requires particular attention - roof joints.

Roof joints cover all the structural joints at the roof: contact with walls and balustrades, bypass of projecting structures (ventilation stacks, chimneys, lightning arresters), aerators, heating isolation joints, water drainage system (internal and external) funnels.

In these areas installation is conducted with the maximum efficiency - in case the leak-tightness of connection spots in roof joints is damaged, moisture penetrates inside the roofing pie. The aftermath will be critical.

In most cases leaks and destruction occur in the places of wall and balustrade connection. During such joint installation at first one should conduct preparatory works, including wall (balustrade) cleaning from the destroying support (plaster), mud and roof cleaning - eliminate moisture, dust, dirt. Additional prime coating application is possible. To avoid the formation of straight angle between the roof and wall (balustrade), it is necessary to make up concrete “hollow moulding” at the angle of 45°. If necessary, the wall (balustrade) should be plastered. Plastering is conducted at the level of waterproofing location, i.e., 30-50 cm. After preparation the main waterproofing layer is applied; it consists of a polymer&bitumen mastic “Abrin”, armoured glass fabric and protective enamel “Abrin C”.


Joint No. 1.1

Diagram of contact area waterproofing

(A - 1 prime coating; B - 2 mastic layers; C - 1 glass fabric layer; D - 2 enamel layers)


Joint No. 1.2

Diagram of contact area waterproofing

(A - 1 prime coating; B - 2 mastic layers; C - 1 glass fabric layer; D - 2 enamel layers)

Another important factor at the conduct of roofing waterproofing works is making up expansion joint. This joint is intended for decreasing loads on the structural components in the spots of possible deformations occurring during temperature drops inside and outside, ground settlement, seismic phenomena, peculiarities of building and erection operation. Expansion joints divide buildings into sections from the ground level to the roof inclusively and make an integral part of construction structures. This joint should pass through the roof layers and coincide wit the seams in the walls and interfloor overlaps. The expansion joint structure and a proper selection of the main waterproofing cover should provide roof waterproofing at building deformations. Ural-Polimer-Lak, LLC, suggests the following way of expansion joint waterproofing.


Joint No.2

Diagram of expansion joint waterproofing

(A - 1 prime coating; B - 2 mastic layers; C - 1 glass fabric layer; D - 2 enamel layers)

Among the roof joints one should pay special attention to the internal drain pipe funnels. This joint has specific structural peculiarities which must not be ignored. Internal drainage is a whole system consisting of various pipes, gutters, sockets, stack and funnels necessary for water draining from the roof. A roof drainage system is necessary for providing the longevity and strength of a building. It is very important to provide funnel waterproofing at the internal drainage and the pipe. Each joint should be covered with waterproofing material which will prevent moisture penetration into a roof void. If the internal drain pipe funnel is installed with the violation of the Construction Directives and Rules, funnel clogging can occur, which causes its overfilling and water penetration into the roofing pie. For this case Ural-Polimer-Lak, LLC, developed and continues actively applying the following diagram of applying the roof waterproofing mastic “Abrin”.


Joint No.3

Diagram of waterproofing internal drain pipe funnel

(A - 1 prime coating; B - 2 mastic layers; C - 1 glass fabric layer; D - 2 enamel layers)

The works on sealing drain funnels should be viewed as seriously as possible to avoid any errors, which in the future can cause adverse effects.

One more important roof connection joint is an aerator. A roof aerator is a special unit intended for condensate drainage from roof void. Moisture penetrates into the roofing pie from the environment or from the inside part of rooms (in the form of vapour and condensate). In addition, some heat insulation materials can accumulate moisture already at the installation stage. As a result of moisture penetrating the roof void, roofing pie material operation characteristics change which finally results in the roof destruction. A properly installed and sealed aerator performs important functions:

  • condensate drainage;
  • eliminating increased humidity air;
  • roof void ventilation;
  • preventing the decay of heat insulation and other roof materials;
  • decreasing roof leakage risk

Joint No.4

Diagram of aerator waterproofing

(A - 1 prime coating; B - 2 mastic layers; C - 1 glass fabric layer; D - 2 enamel layers)

There is a large number of typical structures of roof joint connection with the balustrades (walls), pipes and other roof components. Most of them have quite a high degree of reliability in case of applying quite reliable and long-term material. Taking into account the importance of the integrity of connection joints for the reliability of all the roof, Ural-Polimer-Lak, LLC, recommends using the Abrin materials for waterproofing and sealing. These materials are manufactured on the basis of chlorosulphonated polyethylene and are characterised by increased reliability and durability. In various combinations these materials replace up to 80% of all lacquer and paint materials, lacquers, paints, sealers, roofing membranes and roll materials, and the period of life of chlorosulphonated polyethylene coatings in atmospheric conditions practically reaches 30 years.


ИНН 7430022739, КПП 745301001, ОГРН 1157430000640, ОКПО 34549080
Р/С 40702810904000009845 УРАЛЬСКИЙ ФИЛИАЛ АО "РАЙФФАЙЗЕНБАНКА" Г. ЕКАТЕРИНБУРГ, К/С 30101810100000000906, БИК 046577906
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