karndean fitting over underfloor heating

17 Sep 2010
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United Kingdom

I was going to fit karndean flooring over a floor with underfloor heating, after speaking to a flooring supplier today regarding floor screed i was told not to put down karndean over UFH it will shrink. He was advising me to go for enginered wood. I have looked on net and cant find anything about karndean shrinking when laid on UFC. Does anyone know if it does shrink ? or was this him trying to sell his flooring.

The builders put a sand and cement screed over the UFH pipes to me this looks perfectly level. Will i still need to install a screed such as stopgap 300 over this,or can it just be feathered in parts.

Is there any alternatives to stopgap.
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Hmmm - says alot about your supplier!

I dont deal with Karndean but I know all the suppliers I deal with are OK with UFH under their products (Polyfloor and Distinctive)
As these products are all the same I do not see why Karndean should have any problems - you can always ring them just to be sure

Yes you will still need to screed first

Please do not fall for the its easy to do line though, please consider getting a good professional fitter to install your floor

....just search through all the horror story threads on here if you dont believe me

Thanks for reply i thought the guy was at it , trying to sell me a product he no doubt got more commision from.

Will the whole floor need screeded or just any hi or low spots?

Is there somthing in screed that makes the glue stick better or is it just to make it perfectly flat ?

I have got a full time karndean installer to fit the karndean but he does not screed.

The area to be floored is 112 m2
I have priced the screed which comes in about the £600 mark does this sound right for screed sounds an awfull lot.
actually thats nearly half what I would expect to charge!

If its 112m2 then that equates to £5.36 per m2 which is suspiciously too cheap. Unless that is "lay only" i.e. you supply the screed and they lay it, in which case its a bit dear.

Yes, you need to fully screed the whole area.

A Karndean fitter who does not screed..... hmmmm...... :eek: :rolleyes:

Think you need a different fitter - Shortcuts with this type of flooring lead to very expensive misery. Please do your homework - this section of the forum (floors, loft and stairs) has several tales of woe, all a result of people doing it on the cheap. Having said that I note you are in Scotland and labour rates can be cheaper.
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thanks for your reply.

The £631 is for screed only to cover 112m2 which i was going to supply.That is stopgap 300 from a company on the net called i love flooring seems to be the cheapest i can find.

What screed do you use and what kind of price should i be looking at for someone to supply and screed floor.

I have used the fitter before to fit karndean and he makes a tidy job, but he does not screed.

I was looking at the karndean skim coat that covers 25m2 per tub would this be okay to take any imperfections out of the floor.

The floor has had a sand and cement screed put on it that looks pretty good to me.
@ gilly120....

I am a retailer not a fitter....

We usually leave the choice of screed to the fitter and it does also depend on your floor, its moisture levels etc.
Now you say that you are supplying the screed then your price seems a little high (but not much)
I am stiil a little surprised that your fitter does not screed! - a bit like a carpet fitter who doesnt do gripper!
At the end of the day you have to decide are you happy with the guys you will be using and do not pay them in full upfront!!!!

I wish you luck and please post pictures when its done
If you have had a sand/cement screed installed you will need a DPM (damproof membrane) and a levelleing screed prior to installation of karndean.
Your fitter should know this, why not ask him ?
The preperation is of most imprtance with karndean/ amtico etc.
hi what screed would you use prior to fitting karndean when there is underfloor heating.

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