Roof Waterproofing & Repair

Most roofs in Singapore are constructed using reinforced concrete (RC) which is known to have pores or capillary tracts. Concrete is inherently weak in tension and cracks can appear from thermal expansion and shrinkages as a result of extended exposure to heat. A damaged roof or its deteriorated existing waterproofing system can allow water to seep into the structure which can cause significant damage. Leaking roofs can be prevented if it is cyclically re-waterproofed, maintained and inspected regularly.

Methods & Techniques

Torch-on Membrane to RC Flat Roof

These modified bitumen membranes are pre-formed membrane manufactured with various reinforcements to form a strong, flexible, puncture-resistant material.

It is then installed onto the substrate using the torching method. The edges of the membrane are then overlapped and sealed together using heat to form a continuous waterproof layer over the entire roof. When properly installed by a trained and highly competent applicator, it is one of the most superior waterproofing systems.

We have the multi-building and multi-system experience to assist you in the installation of Torch on Membrane, to provide your building with a virtually trouble-free waterproofing installation.

Liquid Applied Membrane to RC Flat Roof

Liquid applied membrane systems refer to roof coatings that are in liquid form. The coating can be applied by brush, rollers or spray equipment. After application, the coating solidifies either through evaporation of solvents or by a chemical cross-linking process to form a layer of waterproof membrane.

Liquid membranes are usually applied in several coats with a primer or sealer to enhance adhesion to the surface of the roof. Fibreglass reinforcement or polyester nettings may be embedded into the layer of the liquid coating to withstand the repeated expansion and contraction of the concrete roof due to heat changes.

Liquid applied membrane is best suited for waterproofing congested roofs.

Liquid Applied Membrane to Roof Tile

Roof tiles are assembled in an overlapping manner and are linked with nails. When installed at a gradient, roof tiles allow water to slide down effectively into gutters, preventing ponding that would occur if the roof is flat.

However, like most materials, tiles are not immune to wear and tear from constant and extended exposure to the weather. Leaks are often caused when tiles are damaged and when cracks start to form.

Sealants, fibreglass and waterproofing coating may be used to seal the vertical joint between roof tiles. Apart from the overlapping tiles, other problems can arise from ridge tiles, the valley gutters and the roof’s flashing. With the proper preparation and application, an industrial-strength roof coating system can greatly extend the life of a tiled roof.

Liquid Applied Membrane to Metal Roof

In constructing metal roofs, zinc, aluminium composite and steel alloys are commonly used. A large majority of leaks on metal roofs can be attributed to corrosion due to extreme temperatures.

Other problems including improper screwing and inadequate lapping joints can leads to water ingress if not properly treated.

A liquid applied roofing system can be used to waterproof a metal roof. These systems involve cleaning and preparing the existing metal roof surface, applying a primer and then applying intermediate and top coats over the entire surface.