Ply lines have started to show through on a lvt I did on underfloor heating All prep were done correct full nail down 5cm around the perimeter of sheets, expansion, primed the ply to stop delamination (Chinese ply) feathered x2 as the customer has increased the temp on the floor the line are really starting to show, the karndean with high temp hasn't budged. I've only done Is this a matter of cheap ply delaminating with too much heat? Has any one experienced this before? We did another area with no ufh and it's fine.
We haven't taken it up, the feather sanded OK when prepping with no issues, I haven't fitted many lvt over ufh but the one's we have done we haven't had any problems but they've all been screeded over ufh. There would be no chance of screeding when plyed before with the firm this was for, they go the cheapest way about things. We have no control over what products to use.
When ply dries out and shrinks or absorbs moisture and expands the feather will go with it every time and crack it's weak ! Flexy will hold its ground most of the time If I'm fitting Amtico I always flexy coz everything shows through Ply lines nail holes even specs of dust can show through
Do you flexi even if not on ufh?, If it comes to us ripping it up could the flexibility go over the broken feather?
Agree. Unless ur fitting it in a nightclub where it will never see the light of day it needs flexi screed. Sent from my iPhone using Tapatalk
Sounds crazy but did you check the moisture content of the ply and floor before fitting? Sent from my SM-G900F using Tapatalk
Chinese ply are the words that stand out...... Been issues with it since 2013 so stopped using it and use far eastern on standard jobs and sp101 on amtico...... Ply on ufh could have dried and expanded..... A layer of fibreglass screed on top could have prevented it
Hi guys when fitting ply over under floor heating I always glue the ply to the sub floor with Pva adhesive and glue every joint. I also never use poor quality plywood, stick to Malayan or Sp101. Never have joints show through my jobs.
Just to note also Ardex feather is not heat tolerant, the only feather that is or can be used in high temp areas is Uzin 888.
