Car ramp repair and waterproofing

The site is a two-storey above-ground garage cooperative built in the Soviet era. The access ramp to the second floor is made of monolithic hollow-core panels resting on a retaining wall, which had been waterproofed with multi-layer tar paper laminated between layers of liquid bitumen. The total thickness of the old waterproofing layer was over 10 mm. Despite this, the ramp let water through into the rooms below.

Work sequence

To make a structure like this watertight, all layers must first be removed down to the load-bearing structure. Once all layers had been removed, the entire surface was roughened with an ultra-high-pressure washer. After a levelling compound had been applied, the Köster NB 4000 waterproofing system was applied in two coats – a highly elastic mineral waterproofing coating with excellent adhesion properties. Corner tapes were installed in the corners, and reinforcing fabric was embedded in the levelling compound over the panel joints to help the waterproofing membrane absorb stresses caused by cracks.

A 100 mm thick reinforced concrete protective layer was cast on top of the waterproofing. It bonds to the waterproofing layer, so that together with the hollow-core panels it forms a single monolithic, watertight whole.

Materials were supplied by Primostar OÜ.