I'm looking at installing a retrofit "wunda" type UFH system and looking to lay 15mm engineered parquet as the finished floor. Each block is 450mm x 90mm. Reading threads on here there seems to be a lot of problems but with LVT and screeds, but my install is different. Spoke to various manufacturers but there is so much conflicting advice. The retrofit tiles are identical for all the manufacturers and from the advice they;'re giving, I just don't know what to believe. Some suppliers are saying engineered wood can be direct bond, others are saying it must be on a 10mm screed, others a 12 mm screed. Wunda say that engineered wood can be laid floating, direct bond to the tiles or over a screed. As its parquet, it obviously won't be a floating floor so that leaves direct bond or SLC. But...they say if its short plank an d parquet, it needs to be over a screed. They can't say what size equates to a short block and they say it has to be minimum 5mm deep in one instruction, then 10mm in another. So, if engineered wood can be laid direct to the tiles without a screed, why does parquet need to be laid over a screed? Is this because of the herring bone layout? Would parquet blocks installed in a straight linear layout need a screed? If this can be installed without a screed then it would be a bonus. Any advice from the pros?
Screed minimum 10mm from the top of the UFH, Rh% needs to be below 65% then fully bond the wood to the floor. Sent from my iPhone using Tapatalk
So, Wunda are promoting this couple's reno and have confirmed that parquet can be bonded directly to the the foil backed tiles. Check this instagram video where they're glueing it down with no SLC layer. Thoughts.....
Oops...forgot the link. https://www.instagram.com/the_scruff_house/reel/DS63rnVjPD3/?hl=en Screenshot for those without instagram.
If laying engineered wood in plank you can float it with a UFH underlay. If it’s parquet it has to be fully bonded so would need a 10mm screed.
Just watched that video, come Summer when the humidity increases and that floor wants to expand after being shrunk by the ufh all winter, I really don't think tinfoil is going resist the movement of a material that used to be used to split rocks
1. Id no way risk that! 2. I wouldnt take advice from Wunda myself Its crazy because later on down if that ever needs taking up for whatever reason (New owners want to change the flooring) that will be an absolute mess, new ufh....the lot!! Just dont make sense
This is the issue. These floors will need lifting at some point and bonding direct to the ufh system will make that a nightmare. They should always either have a floating floor over them or have a timber/screed subfloor over the top
