ALPOL HYDRO PLUS T system chart

The ALPOL HYDRO PLUS T waterproofing method includes the following layers: – slide insulation layer – thermal insulation layer – pressure layer – undertile insulation layer – cladding

Application of the slide insulation course

First of all, clean the structural slab of loose material and non-adhesive layers. For possible slab repair, and working out the desired slope, use the ALPOL AZ 130 quick setting mortar, or ALPOL AZ 135 levelling mortar. The slide insulation layer should be applied directly to the structural slab. Any flashings should be fixed before application of the torch-on underlay membrane. Apply the membrane in one or two crosswise layers. Then, spread draining matt or 0.2 mm PE membrane and overlap its edges onto the wall to the pressure course height. Instead of the torch-on membrane, ALPOL AH 740 priming and insulation bitumen compound can be applied followed by two coats of ALPOL AH 741 bitumen sealing compound. Application of the pressure course should be preceded by fixing the edge expansion joint to the walls, using e.g. 1 cm thick and 10 cm high Styrofoam strips or adhesive expansion joint tape. Cover the edge expansion joint with the overlapped membrane of the slide insulation course. The edge must be boarded on the outer side.

Application of a thermal insulation layer

The thermal insulation layer is intended to protect the rooms underneath the terrace or loggia from heat loss and to remove heat bridges in balcony or loggia fixing points. It can be done of extruded Styrofoam or EPS 100 - 038 (FS 20) Styrofoam. It is recommended to protect the thermal insulation layer, especially when made of EPS 100 – 038 Styrofoam, from mechanical damage with a coat of 0.15 mm PE membrane.

Application of the pressure course

ALPOL AP 400 underlay floor mortar (ALPOL AZ 130 quick setting or ALPOL AZ 135 levelling mortar) is recommended for the pressure course, which should be at least 4 cm thick. Work in ambient temperatures between +5°C and + 30°C. Once the mix has been prepared and applied, spread it with a skimmer blade or a large steel float. Particular attention should be drawn to maintaining the existing slope of the structural slab and to keeping its direction of rainwater drainage. Recommended inclination of the topmost surface of the pressure layer should be 1.5 to 2 %. The topmost surface of the pressure layer should be trowelled smooth.

Installation of anti-contraction expansion joint in the pressure layer

Additional anti-contraction joint in the pressure layer should be installed when the slab length to width ratio is above 4:1, or when the slab area is larger than 6 m2. The width of the expansion joint gap, reaching to 1/3 coat depth, should be around 5 mm. The work can be continued after the pressure layer has set and dried out.

Application of the undertile insulation course

The undertile insulation is applied onto the pressure course or levelling course for terraces built on ground. In a newly built building, just treat the surface with ALPOL AG 707 primer, at least 3 hours before application of ALPOL AH 752 sealing mortar. In case of repairs, clean the surface well, open cracks and patch it with ALPOL AZ 130 or ALPOL AZ 135 mortar. After the patching has set and dried out, prime the surface with ALPOL AG 707 primer. Before application of the ALPOL AH 752 sealing mortar, bond additional insulation components in the expansion joint gaps, interface between the pressure course and building vertical wall, outer surface edges with flashings and balustrade fixing points.

Gluing sealing tape in the expansion joint

Apply ALPOL AH 752 sealing mortar of sludgy consistency on the surface in belts of the same width as that of the sealing mesh tape ALPOL T1 with some surplus. Then, embed the tape so that it can be pressed into the expansion joint gap to the depth of twice the gap width. Apply the compound again as described above. The cavity formed out of the tape allows its free movement and the expansion joint rope to be placed after the tiles are bonded.

Sealing of flashings

The flashing (drip edge) is fixed mechanically with bolts, directly to the surface, to the wet layer of ALPOL AH 752 mortar, in such a manner to ensure proper adhesion. The depth to which bolts are driven may not exceed that of the pressure slab. Horizontal plane of the drip edge should overlay on the balcony slab to ca. 10 cm. Then, apply mortar of sludgy consistency onto the surface and flashing in belts of the same width and spacing as that of the sealing mesh tape ALPOL T1 with some surplus. Do not apply the compound in the very contact point with the tape. Glue the tape avoiding tension that might obstruct its free movement. Apply the mortar again on the contact surface. If no gutter is provided, the drip flashing must be 1 cm larger than the pressure slab. Its distance from the front edge of the pressure slab should be between 3 to 5 cm.

Sealing balustrade post fixings

Apply ALPOL AH 752 sealing mortar of sludgy consistency in belts of the same width as that of the contact surface of ALPOL M1 seal sleeve with some surplus out of the sleeve. Then, slide the sleeve onto the balustrade post and embed it into fresh mortar. Apply the compound again as described above, and do not cover the sleeve surface at the post with mortar.

Sealing balustrade post fixed to the balcony structure

When repairing a terrace, balcony or loggia with a balustrade the posts of which penetrate through the top coats: cladding and undertile insulation, first, mechanically or chemically remove old paint from the posts up to 20 cm height from the balcony slab level. Then paint them with anticorrosion paint. The ALPOL M1 seal sleeve must be applied around each component penetrating through each damp proof course level.

Fixing balustrade on a new balcony

While constructing a new balcony, terrace or loggia, it is recommended to fix the balustrade post to wall plates or expansion bolts located in the front or bottom of the structural slab. This will allow continuity of courses to be maintained and ensure a long-term trouble-free performance.

Gluing ALPOL T1 sealing tape in the surface-wall interface

Apply ALPOL AH 752 sealing mortar of sludgy consistency on the surface and wall in belts of the same width as that of the sealing mesh tape ALPOL T1 or ALPOL corner piece, with some surplus. Then, glue the tape leaving some clearance for free movement of the tape. Apply the mortar again as described above. After tiles are fixed, press expansion joint rope of appropriate thickness into the cavity form that way. Round the corner edge with ALPOL AZ 130 or ALPOL AZ 131 mortar if necessary.

Application of the underslab insulation course

Application of the ALPOL AH 752 sealing mortar can be started 6 hours after bonding additional components. Prepare mix of sludgy consistency to apply the first coat, and a putty consistency for the second coat. Apply the first coat on the entire surface with a rough paintbrush or brush, rubbing it intensively into the surface, covering also the points in which additional components are bonded. Apply the second and the following coats crosswise in a similar manner or by trowelling. Remember to apply the following coats after the previous one is set, i.e. after around 6 hours, at 20°C. To avoid shrinkage cracks, do not apply more compound than 2 kg/m2 at a time. The coat will be resistant to rainwater after around 12 hours from application. The minimum undertile insulation thickness is 2 mm.

Application of cladding

The cladding is most commonly made of ceramic tiles. Use frost resistant low-absorbing tiles, e.g. porcelain or clinker tiles. Tiles can be bonded after 24 hours from application of the ALPOL AH 752 mortar, using recommended liquefied adhesive, highly flexible ALPOL AK AK 516 or medium flexible ALPOL AK AK 517 liquefied adhesive. Tiles can be bonded with a “combined method” which consists in applying adhesive both, on the surface and on the tile bottom. This method allows the use of ALPOL AK 512 quick setting flexible adhesive, ALPOL AK 513 flexible adhesive, ALPOL AK 514 white flexible adhesive for marble, ALPOL AK 515 flexible adhesive for porcelain tiles or ALPOL AK 511 flexible adhesive for porcelain tiles. Apply ALPOL adhesives with a trowel and float and spread uniformly with a notched trowel with square or rounded notches. Apply tiles and press them lightly against the surface.

Sealing expansion joint gaps and corners. Grouting.

Expansion joint in the cladding can be made using a special metallic or plastic profile with compensating filling or by filling the gap with permanently elastic material, e.g. silicone. Press waterproof expansion joint rope into the gap before filling it with silicone. The joints between floor and walls should always be protected with waterproof expansion joint rope or silicone. Flexible grouts of reduced water absorption are recommended for pointing. ALPOL AH 760 grey epoxy compound is recommended.