BPC Painters | Waterproofing Roofs | Contractors

BPC Painters and Renovators is a top waterproofing company in Cape Town. We are specialist in waterproofing.

Below we explain different waterproofing scenarios and how to effectively treat each problem.

With all the advents in technology and materials sciences, there are a number of effective waterproofing products on the market. Silicone based sealants, acrylic fibre-reinforced paints, polyurethane based sealants, membrane impregnated acrylics etc. However, when dealing with flat roofs or roofs with a slope of less than 1%, the most effective application in the South African climate is bitumen-based torch on membrane. There are a large variety of manufacturers of these products, but we prefer to use ABE products for their 70 years of proven excellence in our market. We recently encountered a waterproofing challenge in Constantia where we felt this torch-on application would solve the endless damp problems the client was experiencing on a flat roof surrounding a glass and aluminium pitched atrium.


The first thing to be done is to determine all possible points of water ingress. I tend to follow the fall of the roof and see where water tends to dam up. This is normally where the water has attacked the old waterproofing system the most and will show deterioration. All remotely questionable materials are completely removed.

In this case there was a considerable amount of acrylic waterproofing in areas with a poor fall (drainage gradient) which is not meant for prolonged submersion. This was especially evident in the box gutter.


Prior to the torch-on application, cement was poured into the problem areas of the box gutter to ensure the water drains out completely instead of damming up as before. Once all the falls are improved as much as possible, all surfaces are dried and cleaned of loose debris. Those areas to be torched or any other bitumen applied must be primed with Bituprime as was done to this flashing area.


Those areas that are too small or do not require re-torching are done with plasticized bitumen applied by trowel as seen below on the roof screw heads.