Got a job to latex/screed on concrete ready for someone to fit wood stuck down apparently , which one do you recommend ? And am I right assuming it has to be water based ....? Plus if it was engineered going down any latex can be used I take it.?
Only mapei do a latex strong enough for bonded wood, latexplan mate or use a decent water based either ardex k11, fballs 300 or mapei's ultraplan to name a few, just make sure you prime concrete first and use a surface membrane prior to wood being fitted.
if a glued down product a surface dpm has to be applied. Even if the subfloor is below 75% RH. You need a compound that is above 20 NM strength so most waterbased and acrylic compounds. Mapei latex plan trade is also fine.
See the job today, one area is having underfloor heating mat , the other areas have the bitumen backing left from the little finger blocks, flooring is going to be floated engineerd so can I use tremco sx 301 or latex trade plan.? I can't see a problem as nothing will actually be stuck to the floor????
i would use fibre reinforced when going under or over UFH help prevent cracking when it expands etc...
What did people do before reinforced fibres were around ? I've used arditex na over mats aswell as tremco don't think there has been any problems yet.......
they used latex based. Latex is fine normally as a weak compound and would move with heat etc. No good for glueing wood to tho. hence you never find 'old' floors with under floor heating and wood floors on top. They all went wrong hence rocking horse pooh.
Oh I see , just read up on the tremco sx 301 ,and it say not suitable for bitumen , this won't be a problem will it ? As you said the wood won't be bonded to it, so in theory it would just be sitting there under the wood and underlay acting as a smoothing compund.?
with all compounds the bitumen should be removed. If going over the top its down to your discretion of if the subfloor is suitable. Normally the weaker the compound the more you can get away with. However you drop strength tho. I hear latexplan trade can take some grief and go over dodgy floors tho. ( Not recommended by manufactorier, just what i heard )
