Adding a wetroom while screeding.

[Lee Edwards]

Hi all. I hope you are all well.

I am.building an outhouse which is going to have a showroom in it. It is going to be a beam and block floor, 100mm pir, UFH pipes and 50mm sand and cement screed. Can anyone advice the best way to create the slope. Actually slope it with the screed or slope it with a former?

Oh, and I have another question.

I am just about to pour my foundations. The structural engineer has said they should be 400mm high, now the height of the finished block and beam floor will be 810mm, the engineer has said to use 140mm blocks to sit the beams on which I think are 215mm high and the beams are 100mm deep. So 810mm - 100mm for the height of the beams leaves 710mm and I think a mortar joint is 10mm. So do I need to raise the height of the foundation to 485mm so there will only be one block and no need to cut any, but then on the outside it has a brick plinth upto dpc which is 150mm above ground.

Thanks for any advice you are able to share.

Regards Muts

 

[23vc]

Re. the wet room I’ve done a couple, one on S&C screed, another on concrete. Both times, I just freehanded the semi dry screed with my trowel a half decent fall around a couple of foot of the trap, which was obviously already in place at that point. Both times, tanking and tiling were all good.

The formers are probably a good shout, but I’ve never bothered on a solid floor.

 

[Lee Edwards]

Now that looks great. Exactly what I am looking for but with a linear drain. I believe a mud pan is a good option. It's just how much screed at the bottom of the fall is not enough. Maybe 10mm of screed on the pir would crumble?

Thanks for replying

 

[23vc]

Yeah you wouldn’t want to go anywhere near down to 10mm, you shouldn’t need to either, it’s only a slight fall from the main floor level. I just scraped the top few (10 mill?) away around the trap and feathered it out. You can, later, adjust things with a bit of self levelling and/or your tile adhesive bed thickness to get it bang on…all depends on the room shape, how much risk of it running where you don’t want it etc …

 

[Lee Edwards]

I see what you mean. I was looking at schluter wetroom kits and some of there formers have a 40mm fall if over 1200mm long.. Well between 1-35 to 1-80. I guess a preformed one that you cut into the screed could be good but I was kind of wanting it to be heated.