A Few Former and Backerboard Questions.

[Youngoggy]

Dear all, I have a few issues in relation to my wetroom that I could do with some sound advice on.

Having ripped up the floor and levelled everything out I am now at the stage were the 6 mm backer boards can be put down ready for tanking and UFH.

As is turns out the backer boards are around 2mm higher than the tray former along its longest edge. Will I be able to loose this difference with adhesive when the tiles are laid or have I messed up!!

Also th backer boards are supposed to be laid on a layer of addy which will increase the difference further. Could I get away with simply screwing them to the ply without the adhesive?

Lastly the UFH I have comes with a probe which is quite thick and it says in the bumf that it should be bedded in a chanel cut out of the floor. Is this possible with backer board and what would you uuse to do it or will it be OK taped to the board and tiled over?

Thanks Rich.:gettree:

 

[cornish_crofter]

With regards to the height difference with the backer boards, I would have thought that you could lose the difference by increasing the fall slightly on the tiles over the former towards the gulley. I did this with a Tilux former that I used on a concrete floor after getting it slightly out of level at one corner. Just build up the SPF that you are using to give you a thicker bed at the top end.

With regards to your other problem. I've never laid the backer board onto floorboards, so I couldn't comment. You've got several options to consider, some of which may not be feasable or advised by the likes of Wetdecs.

1) Stick the boards down as previously intended, this will give you more of a height difference to make up. Make this up as above.
2) Screw down as you suggest, perhaps risking that the boards will not be ridged enough for the tiles
3) Replace the floorboards near the former with thinner ones and lay the backer boards as you planned. This would give you the chance to increase the fall further away from the former, which may not be a bad thing.

Can't help you with the UFH, sorry

Over to the Experts - Wetdecs please......:santa_cheesy:

 

[Youngoggy]

Thanks Cornish, not an exact science this wetroom stuff.

I reckon I should get away with building up as you suggest after all it's only a couple of mil :dizzy2:

Any advice on the UFH wetdecs :santa_cheesy:

Thanks Rich.

 

[wivers]

You can score a channel outa the backer board with a good stanley knife and then us a small wood chisel to chase it out.

 

[Youngoggy]

Excellent :20:

Thanks Wivers.

 

[wetdec]

For future reference............@ everyone

Wood floors.....Ply then weyrock then an 8inch cavity

How much heat do you think your going to lose through this floor area..........if any its negligable.

A 6m2 room will use approx 800 watts per hour approx 12p

If you have the ufh switched on for an hour a day you will need to take 800 showers to pay for the insullation boards.............

Look at the height probs we have with wet rooms and then do the math.

My opinion your wasting money and time.....................


..

 

[Youngoggy]

Hi Wetdecs,

not sure what you are getting at but my floor is a normal chipboard floor overlayed with 6mm hardie backer boards, so no 8" gap!

I didn't use insulation panels as I like you reckon they are a waste of money and it is only a small room at 4 m2. I will be tanking it and then laying the UFH on top of that hopefully before Xmas :gettree:

Will let you know how it goes.

Thanks Rich.

 

[cornish_crofter]

I think what wetdecs is trying to get at is that he considers UFH on a first floor a waste of time, as much of the heat is likely to travel DOWN into the ceiling void then permiate through the ceiling to the room below.

Although heat rises in general, it is also likely to take the easiest route, and if you've got tiles or tanking plus boards, it's likely to avoid the tiles, and go south instead.

 

[Youngoggy]

Mmmm not convinced thats what he means. He Says "A 6m2 room will use approx 800 watts per hour approx 12p" so a couple of hours a day is 24p! I appreciate that if I had used insulation boards it would work out more expensive but I haven't used em.As for the heat going south I guess there is only one way to find out,I will fit the UFH nd see how it goes. I could always put me shoes on in the shower if the floor stays cold.Any advice Wetdecs?

 

[wetdec]

It was a general opinion as to the use of insulation boards wasnt directed at you m8...........

@ Cornish No the floor boards + the joist void is insulation enough its only a small floor space.........

Take a double glazing unit 2 sheets of glass with air between creates an insulation space, same applies to a wood floor and ceiling below the air is the insulator along with the wood so extra insulation is not really required imo..........


..:santa_cheesy:

 

[DHTiling]

I am with wetdec...no need to insulate a timber floor over joists...wasted money.....and youngoggy...it wasn't meant as critism at you...just general info for use on timber fl oors...you have used a cement backerboard not an insulation board so no panic...

 

[Youngoggy]

Thanks Fellas that clears it up, thought I was on the right track but been new at this I am on a bit of a steep learning curve to say the least.

Can I just say that I would have been lost without the help and advice from the contributers to this forum. Great work guys keep it up :santa_cheesy:

Thanks Rich.

 

[Uheat]

Running an underfloor heating system can cost as little as a few pence per day depending on the conditions, the more insulation your room has the more efficient your heating system will be.

Rough warmup times based on different sub-floors are below

Thermopanel or Ekoboard - 15-30 Mins
Timber Flooring - 30-60 Mins
Insulated Concrete - 2-3 Hrs
Un-insulated Concrete - 3-5 Hrs

 

[DHTiling]

Aaron... I think un-insulated concrete can take more than a day to warm up...just depends upon thickness of the base....the base heats up before any noticable transference to the tiles....IMO.

 

[Uheat]

Thanks for the comment Dave.

To a certain degree you are correct but it really does depend on the individual conditions like you have said, thickness off the base, size and type of room, even as much as the outside temperature.