Self re-builder doing bathrooms in Bath

[aviator99_uk]

Hi Guys,

I'm the not very proud owner of a 10 yr old timber frame building in Bath. Which is plagued by design and build issues and I have had to virtually re-build it, look at "Homes from Hell" next spring.

Anyway, I have an on-suite and a bathroom on the 1st floor which both leak like a sieve and have caused timber and plaster issues and so have never been used (apart from to realise that they were un-usable).

This experience has kinda soured me and as a consequence I am doing belt and braces (with a bit of string just in case) on evrything I do.

I am now doing these 2 areas, I have taken the wall tiles off, the walls were normal pbd skimmed and painted then tiled, no bond between paint and skim so the tiles came off whole, I have lifted the floor tiles,floor is 18mm T&G chipboard, bond between chipbd and tile was average and about half the tiles came up whole, the grout between tiles on the floor was cracked as you might expect.

The pbd is in the skip and the timber frame exposed, only slight mould damage evident, and the builders had put up a 1000 guage poly sheet between frame and pbd, the spread who did the pbd must have had issues getting his board to fit as he took his stanley to the plastic in several places, and the plumber did much the same, and then the electrician must have as well, so if it ever might have worked after the trades had been in it didn't stand a chance, the shower spigot wasn't secured and water just went from the back of the spigot past tile, past pbd, past plastic (no attempt to collar seal) and down to the floor and found its way through a big hole where some one had ****ed up and not made good, to the ceiling downstairs.

I am proposing :

Make good walls with a screwed on concrete board like 9mm "no more ply", or hydropanel, or aquapanel, or hardi. Make good the floor with 6mm "no more ply" or similar (screwed & glued). There will be a height diference at the floor threshold so I need to find a trim of appropriate height (schluter / gemmini/ others??).

The floor can then have a decoupling membrane (ditra / others) and the walls a waterproof membrane (kerdi / homelux / others) with corners and overlap strip and collar seal for pipe work, also need a seal for a separate 4" vent pipe.

Job can then be tiled.

questions:

Threshold trim strip, must be others on the market but I'm not finding them.?

Sealing collar for a big pipe?

What products (primer / adhesive / cement) are best to use for bonding membranes ( waterproof and decoupling) to backer board on wall and floor?

 

[Dontiler]

:welcome:

 

[White Room]

Hi and welcome

Do you have any deflection on the bathroom floor

 

[aviator99_uk]

Wedi is certainly one of the products I'd look at but...

Deflection :

There is a fair amount of deflection because the joists are a "strange" size kinda 7" by 3", if you look at the span tables they are right on the limit for domestic even on the 12" on center that has been used. I think the designer gave himself a 200mm (8") grid that he worked off and wanted the joist and floor to "fit" into that asthetic probably because of how he drew the plan. As an engineer turned chippy I would have gone for 10*2s and made the rest suit, but we have the last couple of inches of the 7*3s exposed as a "feature" in the downstairs ceiling.

Aside from the fact that the builders didn't leave me with a decent chipboard floor, (the guy who plumbed in the waste obviously didn't have the right size trap and he didn't get what he had right first or second time), put a 20 stone bloke in the en-suite and you could probably measure the deflection of the floor with a tape, I can measure over 1/2" of "sag" mid span of the first floor joists which has just "happened" over the last 10 years under its own weight.

Its a timber frame which will move, its badly designed and although I've replaced all the rotten timber (another story) I have to assume that there is no reason to expect other than that there is going to be movement.

Thanks for the input on the trim and the sticky stuff.

A

 

[White Room]

Just an idea I saw done once on a job, steel plates were fixed to sides of the joists to give strength and stop deflection.

They were fixed the whole length of the joists and bolted thru, they were solid bits of steel though.

 

[aviator99_uk]

In one place where I had to replace the floor I have actually had to do that. However as the chipboard floor is laid under the walls of the first floor to get at the joists to strengthen them means either skipping the ceiling or having a lot of work trying to put noggins in to support the floor off something, and the first fix is bound to be in the way, and as the ceiling comprises of a gazzilion 9" wide strips between these stupid exposed beams I'd just sheet over and loose the design "feature" and also the missus.

But right idea.

A