freestanding bath, floor support, tile choice

[newplumb]

Hi guys

About to embark on a bathroom job in the next month and would really appreciate some advice please.

It's a first floor bathroom and the existing floor is joists overboarded with chipboard. The customer would like a freestanding bath but hasn't yet decided whether to go for reclaimed cast iron, or a lighter modern one.

I'd like your opinions on what kind of flooring/tile combinations would be best for each of these two options. Given that the substrate would be going straight on to the joists, I'm guessing 3/4" ply probably in both cases, in which case do you think I could get away without building a plinth if the bath was cast iron? Then what options for tiles, to avoid cracking? Porcelain I guess, but anything else?

If the customer goes for a lighter modern bath could I get away with a thinner substrate, and ceramic tiles?

Thanks - looking forward to your replies
Matt

 

[david campbell]

Hi guys

About to embark on a bathroom job in the next month and would really appreciate some advice please.

It's a first floor bathroom and the existing floor is joists overboarded with chipboard. The customer would like a freestanding bath but hasn't yet decided whether to go for reclaimed cast iron, or a lighter modern one.

I'd like your opinions on what kind of flooring/tile combinations would be best for each of these two options. Given that the substrate would be going straight on to the joists, I'm guessing 3/4" ply probably in both cases, in which case do you think I could get away without building a plinth if the bath was cast iron? Then what options for tiles, to avoid cracking? Porcelain I guess, but anything else?

If the customer goes for a lighter modern bath could I get away with a thinner substrate, and ceramic tiles?

Thanks - looking forward to your replies
Matt

22mm ply would probably be the best idea due to the wight of the cast iron bath,other options for floor tiling could be travertine,i would probably not use ceramic on a floor as they tend to wear with traffic

 

[newplumb]

Thanks David,

So no need for a plinth then if I went for 22mm ply fixed to the joists?

 

[White Room]

If it is a cast bath would putting some extra noggins between the joists and using porcelain with a 100% bed

 

[Ajax123]

I guess there are point loading and deflection issues with a free standing cast bath on timber floor. Is this likely to affect the choice of tile and adhesive. I just asking this one - I have not got the answer...

 

[macten]

Cast iron bath + water + person is some serious weight.
I'd want to get a builder in to professionally strengthen the floor first before I took that risk.

 

[newplumb]

Thanks for all your replies so far. Some useful tips there. I think the customer is now favouring a modern acrylic rolltop bath, so hopefully that's one less problem to deal with.

However, for the floor tiling they would like black and white squares (diamond format), and they have their eye on "Forte" tiles from TileGiant (99p each). I'm pretty sure these are 300x300 and about 10mm thick ceramic. Obviously as the tiles under the bath will be visible, I'm still a bit concerned about cracking. Do you think these are suitable to take the weight of an acrylic rolltop bath?

 

[Deleted member 1779]

When I put this free standing bath in I put extra noggins into the floor joists below to improve the rigidity of the floor.

Had to cut holes in the middle of them to run the 40mm bath waste.

The bath is a lightweight contemporary bath so much less heavy than cast iron. Sits on basic floorboards (tongue and groove) with 12mm ply on top.

PS: If you need perfect holes in your porcelain floor tiles for the waste pipe then we do a 45mm diamond tile drill.

 

[newplumb]

Thanks. So even with a lightweight rolltop, you would recommend 22mm ply (not 18mm - I'm taking this from your example of boards plus 12mm ply) plus joist strengthening? Is that right?

Do you have a view re the tiles I mentioned in my last post?

Thanks
Matt

 

[david campbell]

would use a porcelain or natural stone tile for a bathroom floor,and would make sure there is 100% coverage under the tile making the chance of any breakages virtually nil