Are Bitumen products still the go to products in waterproofing?

Bitumen products - are they still the way to go? What use do they have in the waterproofing industry and how are they used?

When we started Gripset, we were pioneers in using bitumen technology and we were one of the first companies that had developed water-based bitumen technology and using with polymers. Now that's such a commodity-based system now, it's been bastardized, but back in the mid-80s it was fairly innovative and very, very different. So bitumen has always been referred to as the go-to product because it's waterproof, but has that now changed?

It was used in the early days because it was really one of the only polymer technologies that was around then other than sheet systems, so bitumen was very well known for bitumen sheet membranes and then there were a lot of solvent-based bitumen products that were out there, and you still see some of those dinosaurs around the place. There was the water-based polymer bitumen products like our Gripset 51 that we developed and brought out to the market. They still have a place in the industry, but back in the day it was the only alternative to tying on a substrate.

There weren't many liquid polymer systems in the market in the '80s and early '90s. There were a lot of companies actually using liquid bitumens as the membrane to tile over. Now it didn't impact the waterproofing, but it did impact things like the tile bed at tiling because there was a discoloring because of the black and what happens with bitumens is they do soften. That doesn't mean they fail, but they soften with thermal temperature. They go quite hard in the cold, very softened with warmth, and then what happens is you get an emission or a yellowing effect and that would be absorbed with anything water based, so things like tile adhesives, grouts, and there used to be a lot of complaints in the market where white tiles or light-colored tiles will be applied over a bituminous surface and there'd be a yellowing effect. They could see these yellowing stain in the tile and that all came through what we call the bitumen bleed. It wasn't really the bitumen, but it was the emissions through the bitumen and some of those surfactants that would come through and cause that discoloring.

So we've progressed a lot since then. As you know, Gripset's got many products in its range for tiling over.

However bitumen still has a place in the market, particularly for things like underground applications. Our Gripset 59, or our Gripset 51, they might be entry-point products in the market, but they still have a place because they are very cost effective, very easy to use, and they stick to everything. So what is great about them if you're going on, and I can only talk about our bitumen products but I know our competitors' is very similar, going over metal surfaces, poorer substrates, a lot of the plastics out there, they bond really, really well. If you're using a solvent-based bitumen, you need to be careful on what you put it on because that can attack the product, particularly some plastics or water-based systems that they will have a reaction to, because that solvent will have a negative reaction, but a water-based bitumen tends to bond to most things, particularly if it's got a polymer in there. It is an opportunity to still use it for what we call entry-point applications. A lot of our landscape customers still use those products. They have a place in the market.

There's been a number of products that have still progressed from there, like I know our bitumen products that used to be used like gospel underground, now we've got things like our Gripset C-1P, or our Gripset 2P, and some of our even polymer products that are used for underground applications in lieu of the bitumen, because the other issue with bitumen and underground is, when you come above the soil line, if you've got a render or texture over it, the same reaction to tiles. It will bleed or impact the render or the texture, whereas if you've got a cementitious product like the C-1P or our polymer systems, you can render or paint over them and there's no issue at all.

So that's something to take into consideration if you still are using bitumens out there, not to say you can't, but you need to find out when you can use bitumens and when not to. There was a time where they were the solution to everything. Now they have their place like everything else. We're much more knowledgeable and we know exactly what we're doing with it, but for whatever you do, if you ever see it in a wet area where you've got to tile or render over, call your builder, call your client, do not do that. That is red alert because that's going to impact the finish, and if it doesn't do it straightaway, it likely will over time because bitumens will always have a reaction to surface temperature changes. They're not as resilient to surface temperature changes, so hot and cold will change the stability of the surface.