Underfloor heating & LVT

Hiya all,

I have a customer who is moving into a small retail outlet, she has picked her lvt, but has complained that the shop is very cold, so has asked if she could have underfloor heating fitted prior to her new flooring going down.
It is an asphalt sub-floor so would have to be the "electric matt type".

Is it ok to screed over this type of matting and if so, at what thickness?
Also, does it then become necessary to use HT adhesive rather than PS.

Personally, id rather she just put a heater in the corner, but we must keep the customer happy, mustn't we?

Thanks

 

I've screeded over the matting but can tend to float if its not stuck down properly (and even then some parts still float). Youll need to be at the very least half an inch (12.5mm) over the top of the wires as well.
You will most definitely need to use HT or even epoxy glue and then the heating will have to be introduced gradually.

 

It's not recommended to put to thick a screed over asphalt. Think its about 6mm max.

 

I'm in the middle of a job right now with electric UFH. It's made by Ebeco, then I'm going over it all with jumpax/versalay. It's probably the best UFH system I've seen, everything very neat and organised. I'll post some pictures when its finished.

 

You can you F46 mate. In fact F.ball say its better on underfloor heating the their HT.

 

Are using heatpak mate? I've used it and think its a pretty good system

 

Thanks for the input guys, Jambo look forward to seeing those pics mate.

 

Fitting the Van Gogh on Monday/Tuesday. Post them after that

Merit, it's the Ebeco foil kit. The packaging says its for wooden and laminate floors, so had to get the go ahead from them first for LVT. As mentioned above, one of the tidiest systems I've seen and the versilay feels great to walk on over the top. Seriously tempted to make a mini display for the shop.

 

Sounds like a good idea mate. The shop I use to work for did a lot of electric ufh with the Amtico sales.

 

does it have to be installed by a qualified spark tho?

 

As promised some pics of the job. Fitted pictures haven't come out as clear as I'd like :-(

 

Can you explain each picture jambo

 

If you have a nosey in my album, I've labelled each stage. There's a few extra pics as well. I spoke to the Ebeco direct in Sweden today and to their main distributor in the UK with a view to installing a small display of this system in my shop. Probably the neatest (and cleanest) systems I've worked with.

 

In fact, I've only put basic descriptions. So..........
UFH System
The subfloor gets covered with Ebecos own underlay product, it's a foam board with a bit of give and provides decent cushion for the UFH matting. Then the matting is unrolled on top in strips, the strips are then connected at the ends with a crimping tool. The matting is then covered with a poly sheet, if the sheet needs to be joined you give it a 200mm overlap and seal with tape.

Flooring
Lay the first layer of versilay/jumpax using wall spacers (approx 6mm). The first row is cut in half on its length and shortened by 300mm so that the second row gives a good over lap on the joints. The second layer gets the same spacing all the way. Once the versilay is completed I like to go over al the joins with a scraper and sander to take down any raised edges. On my one I had to fibre screed an opened doorway to meet against an existing floor that I fitted years ago, lift the now redundant cuts planks to allow new planks to be merged in as if they had always been there. Opinions and experiences will vary next but I fit the Karndean tight to the edge as if on concrete or ply. I know some folk leave an expansion gap when fitting onto versilay but so far 100% of installs have never moved so I go tight.

Sorry the photos aren't any better but you get the idea

 

ok, silly question time from me here
Why is the poly sheet between the heating system and the jumpax?
Shouldnt it be on the subfloor to stop in moisture etc getting to the electrical system?
Isnt the heating going to be constricted tryng to penetrate the poly sheet?
Jut a few random thoughts that occured to me
Am prob way off base but better to ask and be enlightened than not and be forever in the dark lol

 

Mike, I asked Ebeco the very same same question. They advised the sparky to lay the foam boards direct to the subfloor and the poly sheet would act only as a protector sheet between the foil kit and the jumpax. Type in Varmefolie timelapse into YouTube and it shows you a quickened version of the process. Interestingly though if it was solid timber being laid they say not to install the poly and lay the timber direct to the elements.

 

I've used jumpax over ufh with Amtico on top. Poly over anhydrite then jumped.
Admittedly a different scenario.