The science and skill of torch-on membrane waterproofing

Heating and melting bitumen

First-class waterproofing takes skill. At Danrae Group, we’re able to provide quality and effective waterproofing solutions because we have decades of experience, proven processes and a fantastic team of waterproofers trained and qualified to lay every type of membrane.

Torch-on bitumen is a relatively common form of membrane for waterproofing, but not an easy installation for the uninitiated.

We take a look at what’s involved, when torch-on membrane is most suitable and why it is an optimum choice for long-term and effective waterproofing solutions.

Torch-on membrane

What is torch-on membrane?

Torch-on is a flexible membrane containing bitumen and a variety of polymers. It contains asphalt in one of two forms: Styrene Butadiene Styrene (SBS), a rubber modified asphalt, or Atactic Polypropylene Plastic (APP), a plastic modified asphalt.

Torch-on bitumen is heat activated, so applied to the surface using a blow torch. We then add a layer of polymer to enhance structural integrity. Membrane edges are also bonded with heat, giving us the flexibility to cut and shape it to fit any space.

APP is quicker to install but less flexible and hardwearing than the SBS type of torch-on. SBS requires a longer installation process as it takes longer to heat. It is very flexible however and has a very long life span. Both types of torch-on installation are non-toxic and non-carcinogenic.

Danrae Group Planter Box Project

Torch-on benefits and best applications

Torch-on membranes are robust and durable, with UV and heat-reflective properties. Additional benefits include guaranteed membrane thickness, double thickness, long-term durability, vapour distribution base sheets and root-resistance.

Torch-on membranes are also non-water soluble so suitable for very damp or submerged areas such as basements, tanks and swimming pools.

At Danrae Group, we frequently recommend torch-on membranes for projects ranging from luxury apartment blocks to watertight planter boxes. And we find they can be a good option for flat roofs, which are more susceptible to storm damage, extreme weather and blockages, that impact adequate drainage.

Mat at the roof using torch

Our torch-on specialists

At Danrae, we have team members highly skilled in torch-on membrane application. Christian Xuereb is a Remedial Waterproofing Tradesman who has been in construction since he was 14 years old. A master of all trades, his skills include bricklaying, rendering, waterproofing, plastering and one of his favourites, laying torch membrane.

Zach Smith is another of our Remedial Waterproofing Tradesmen, and he gained extensive training and experience with torch-on while living in his native England.

“I do all sorts of waterproofing, but I specialise in torch-on membrane. I learnt everything about it while I was a roofer in England for ten years. You use a blow torch and it’s harder than it looks, plus there’s a lot of detail involved. I’m passionate about torch-on… and about doing every job as you’d like it done in your own home.”

Zach installed torch-on for a Surry Hills luxury apartment block that had been plagued by waterproofing issues for decades. With our extensive in-house expertise, we were able to provide a customised waterproofing solution that also included the installation of a PVC membrane for the rooftop’s tennis court.

Tennis court

Comprehensive waterproofing solutions

Danrae Group has the capability and dedication to provide comprehensive end-to-end waterproofing,  including full project management and ongoing preventative maintenance.

We know that thorough waterproofing solutions will last – and help prevent the onset of major issues such as concrete cancer that can lead to large-scale remediation and impact property value over the long term.

So contact us if you need a quality torch-on membrane installation from the team skilled in first-class and comprehensive waterproofing solutions. Read more articles about membrane waterproofing.

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