Waterproofing of balconies and flat roofs

Terraces represent roof type constructions, which are separated by open areas, built directly on the ground or any other fundament (occupied or utility rooms, garages, etc.). They are means to increase the living area, especially in areas with warm climate because even thought they are placed outdoors, they still create enough home comfort. There you can grow flowers, put a swing, table and chairs, and even a swimming pool.

Different factors have influence on the terraces – rain, sunshine, industrial gases, heating and ventilation of buildings, human activity and others. Each of them can cause different damage, which can lead to water penetrating the living spaces. The greatest loading on the terraces, especially when they are covered with ceramic tiles and placed over heated premises, comes from the large temperature fluctuations (reaching over 100°C) and the linear extensions, which they produce (about 1-2 mm for each 1 m). Very critical are also the water loadings, to which the terraces are subjected – the poring rains, the accumulating and melting snow. The freezing and thawing of water in the pores of the material (ceramic coating, grout, adhesive for tiles, etc.) drastically reduces their durability and destroys them.

The life of a terrace depends mainly on the quality of its waterproofing. As with time the waterproofing wears off and it gets damaged (mechanically or due to climate variations), in order its efficiency and life to be increased it is recommended the implementation of double waterproofing. Extremely important are the details on the connections with the boards and walls, the drainage systems, chimneys, wiring, etc. Besides the correct waterproofing on the terrace, in the system mandatory has to implemented in addition a quality thermal insulation, which will protect the premises beneath it from overheating in the summer and cold in winter.

The waterproofing system HYDRO аnd SPLIT PROTECTION² is designed specially to withstand the adverse weather conditions and temperature fluctuations. It provides the possibility to adapt the terrace to the deformations, that appeared afterwards, preserving the effectiveness of its insulation and ensuring its long life, thermal insulation and waterproofing.



1. Filling up the bigger unevenness with TERAFLEX® CONSTRUCTION ADHESIVE.

2. Priming with contact and bonding primer TERACONTACT® for creating a better contact surface.

3. Making a slope of 2% with CIMENTOL® FLOOR SCREED.

4. Priming the surface and applying waterproofing membrane (the individual stripes should overlap 8-9cm)

5. Installation of horizontal drainage and laying insulation boards TERMOFLEX® EPS W-40 (the joints between them are filled with TERAFLEX® PU PROFESSIONAL).

6. Implementation of reinforced cement screed with CIMENTOL® FLOOR SCREED, as on each 4 m an expansion joint is places in it with width 1-1,5 cm, which is filled with PU sealant.

7. Applying the first layer of two-component waterproofing insulation HYDROZOL® with roller, brush or trowel (5 days after the application of the screed).

8. The connecting and expansion joints are sealed with SEALING TAPE, and for the flor drains is used HYDRO INSULATION SEALING COLLAR FOR FLOOR DRAINS

9. The second layer elastic two-component waterproofing insulation HYDROZOL® is applied 4 h perpendicularto the first. The total thickness of the two layers should be 3 mm.

10. The tiles are bonded with highly flexible adhesive TERAFLEX® GOLD or with super flexible adhesive TERAFLEX® PLATINIUM for elastic bonding on critical bases (72 h after the implementation of the second waterproofing layer).

11. The joints between the tiles are grouted (48 h after laying the tiling) with elastic grout TERAFLEX® GOLD SELECTION or TERAFLEX® SILVER SELECTION, which have powerful water repellent and antibacterial effect.

12. Corner, connection and expansion joints, as well as the places where the valves and fittings are connecting are sealed with polyurethane sealant TERAFLEX® PU 40 FC or TERAFLEX ® PU 50 FC.




1. TERAFLEX® CONSTRUCTION ADHESIVE (Universal repair solution for filling up and leveling irregularities for indoor and outdoor conditions)

2. TERACONTACT® (Contact and bonding primer for critical and non-absorbent bases, which ensures secure adhesion and bonding of floor coverings, ceramic lining adhesives and new concrete, indoors and outdoors)

3. CIMENTOL® FLOOR SCREED (Cement based floor screed with universal use, for manual application)


5. TERMOFLEX® EPS W-40 (Thermal insulation boards from EPS with extremely strong loading pressure resistance, for thermal insulation of heavily loaded places as an element of an integrated thermal insulation system)

or TERAPOR® EPS NP-35 (Тhermal insulation boards from graphite EPS with increased thermal insulation properties and extremely strong loading pressure resistance, for thermal insulation of heavily loaded places)

7. 9. HYDROZOL® (Highly elastic two-component cementitious hydro insulation surfaces which forms strong, continuous and durable waterproof membrane for construction elements, subjected to a constant water loading)

8. SEALING TAPE (For elastic waterproof bridging of expansion, edge and other active joints)

10. TERAFLEX® PLATINIUM (Highly flexible, water and frost resistant adhesive for thin layer application of ceramic linings and granite tile floors (Granitogres™) over deformable and fine polished surfaces)

or TERAFLEX® GOLD (High strength, flexible adhesive for thin and thick layer application of large and heavy lining tiles and stones on critical bases)

11. TERAFLEX® GOLD SELECTION (Elastic hydrophobic grout with sparkling (brocade) effect highly wear-resistant and protection against mould and mildew, for joints with 2 to 25 mm width)

or TERAFLEX® SILVER SELECTION (Elastic hydrophobic grout highly resistant to dirt and with protection against mould and mildew, for joints with 1 to 6 mm width)

12. TERAFLEX® PU 40 FC (One-component polyurethane sealing and bonding mass for highly elastic and leveling pressure sealing of pressure-loaded joints and bonding in construction and machinery construction) 

or TERAFLEX ® PU 50 FC (One-component polyurethane adhesive-sealant for extremely strong and highly elastic bonding in construction and machinery construction).



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