Fast drying screeds for levelling & backfilling…
- Products & Services
- Ardex A38, fast drying screeds, polyurethane cement, polyurethane resin floor, polyurethane screeds, Pumabulk, Pumadur HF, resin floor installers, resin flooring, Sika Purcem, Tramex, Ucrete UD200
- 9th December 2020
Time & again we come across the same problem…concrete which has been poured the day before we attend site!
The above is a bit of an exaggeration. Most people have the sense to pour their slab or backfill around a new channel at least a couple of days before the resin floor installers turn up. But it is fairly common for us to check on our clients progress & stop them from putting concrete in a hole less than a week before our intended start date.
As experienced installers we know too well that the construction moisture from a damp substrates can lead to failure. This is why we regularly test substrates for moisture content as some systems are much more sensitive than others.
Saving a few quid by using a standard screed or concrete mix can mean holding up a program & cost production.
Polyurethane cement hybrids such as Sika Purcem or Ucrete UD200 can be applied to 7 day old concrete, providing minimum strengths are attained. Many epoxy systems are much more temperamental & care should be taken when apply to new slabs. Testing slabs using moisture meters such as the Tramex CMEXpert II can be vital in making a decision to proceed using a certain product. If the readings you get are unfavourable you may be reassessing the specification, adding cost and or time to the project.
To prevent resin flooring failures & hold ups to construction programs due to issues surrounding construction moisture we recommend & use a range of specialist products. The products we use must quickly, suitably cure & be non / low shrinkage.
Pumabulk – Polyurethane Mortar
A firm favourite of ours, which we order by the tonne, is Resdev’s Pumabulk. This product is well know in the resin flooring industry, everyone seems to use it! Based on polyurethane resin technology it can be used to fill deep holes & can be topped with polyurethane floor screeds, such as their Pumadur HF, in a matter of hours!
Another product we use time & again is Ardex A38 screed. This product can be used to directly replace cement in your screed mix & no matter what thickness you install at you can carry on with your floor installation in 48 hours. The Ardex ‘Ardurapid’ range of floor screeds, levelling compounds & mortars lock the moisture within the matrix of the screed. On occasion we have laid on A38 screeds within 24 hours without problems – but be aware you do this at your own risk!!
Polymer Modified Sand / Cement Screed
An alternative to A38 is the good old polymer modified sand & cement screed. Years ago this would be our only option, and it is still a good one. Curing time is dependent on screed thickness but time needed before you can carry on your flooring install can be seriously reduced by replacing some of the guaging water with a good quality SBR. We would use this on larger jobs like screeding multiple rooms to falls in fairly thin sections. The addition of the polymer / SBR will also increase the strength of the screed.
Products mentioned above are definitely our most popular but we’ve used loads more & specify based on the environment we’re looking at & our experience! If you have a query or would like advice please get in touch.