Hi all

I am planning my first UFH project in my small bathroom.
My concern and question is when I have glued the heating wire to the insulation board and start tiling how do you protect the heating wire on the floor that you will have to kneel on.
Is it just a case of using sheets of cardboard on the floor to protect the element, how resiliant are they?

Many thanks.............................

I use a flexible self levelling compound and cover the whole area, this also protects the heat mat getting damaged when you spread your adhesive and stops potential voids and hot spots from forming

Thanks for the speedy reply, the thing is I am not using a heating mat, its the loose wire installation.

I thought and have heard the idea was to spread a screed of tile adhesive over the wire and lay the tiles straight away in one process as such...?

Cheers......

heat mat, loose wire, same priciple. Some people do use addy instead of slc, but I prefer to use slc

Hi Doug

Oh I see, well actually I still don't understand.........!!!!

1. Do you cover the whole area first with SLC or addy then let it go off then tile?

2. How do you protect the wire whilst you are laying the SLC or addy, as you would be standing/kneeling on it?

3. Can you not do it in one process using addy in an 8mm screed and tile on top as you go, surely this would be stronger too?

Cheers.............

after you've fixed your loose wire down, flood the area with flexible slc, it's very fluid and gets into all the areas completely encapsulating it. Doing it this way ensures a more even heat distribution.When laying the slc use a soft kneeling cushion and a non-metallic trowel or shortish length of batten to distribute the slc around the area.

Got it now, thats great, many thanks Doug....................

Can anyone recommend a quality SLC and where to get it from...?

Cheers.....................

Mapei Fibreplan
Mapei LatexPlan Trade

Get it at Tile Giant....may have to be ordered though depending on what they stock.

Hi Madman,

I'll second the Mapei Fibreplan, just used it myself to cover a Devimat, used 2 bags over 5 square metres, the matting and thermal sensor were just a smooth, clean surface to tile over.

Steve

Is fiberplan suitable for ufh?

forget that last post, I was thinking of something else doh!!

And wear trainers or other soft soled shoes

either of the above, fibreplan is better, latexplan is cheaper.

Originally Posted by Scottley

And wear trainers or other soft soled shoes

ARRRRG Scot, what about PPE/ HSE, and all that. Only joking I agree slc is better option, imo.

Madman, one more tip...before pouring the SLC, double-check that all the wires are securely attached to the floor.

If not, a loose wire can "float" to the surface of the wet SLC and then it's too late to do anything about it when you see it happening from the other side of the room and 15 bags are on the floor...uhhhh, nothing like that ever happened to me or anything.

Originally Posted by Rob Z

Madman, one more tip...before pouring the SLC, double-check that all the wires are securely attached to the floor.

If not, a loose wire can "float" to the surface of the wet SLC and then it's too late to do anything about it when you see it happening from the other side of the room and 15 bags are on the floor...uhhhh, nothing like that ever happened to me or anything.

Good point, cheers.......

How often should the wire be secured with glue, every 50mm for example or should it be glued its full length?

Also is the regular glue supplied with glue guns ok to use on the cable and insulation board?

Cheers....................

Any 'hot glue sticks will do, i just buy the cheapest!
If you have the patience and the glue stick the lot down if you are concerned but not necessary as long as no possible 'floaters' as rob z said

i like to use a 'monitor' from Uheat, this gives you assurance that the mat /wire is ok all the way through the installation, might help your confidence

Madman, we usually skim the wires with thinset (I think is what you call addy? John, help me out here please ) in order to hold them down. Sometimes, however, we don't have time and can't do the extra step. In these situations, we secure the wire every foot or so. Every 50 mm would be about every two inches, which I think isn't necessary. Where the wire is straight, you could secure it farther apart than every foot, I think. But at the turns...every two/three inches is probably OK.

And I think this varies with the mats. NuHeat wires are thick in places and it seems like we have to fight with them more to get them to lay down.

The use of a monitor like Faithy mentions is well worth the money.