Whats wrong with my tiled floor?

[actionjackson]

Hi all,

Great forum with a wealth of knowledge.

Here goes with my first post, i live on the first floor of a new build (5 yrs ago) converted granary. My bathroom is porcelain tiled and over the last 2 yrs a number of tiles have started to crack.

I decided to investigate (under the bath) what they have been laid onto and it appears this is the setup-

- Tounge and groove chipboard floor
-17mm floating plywood on top of chipboard floor
- 17mm Tounge and Groove on top of plywood
- Tiles

I cant tell without removing tiles if the top level T&G is fixed to the plywood however i can tell you the plywood appears to be unattached to the main chipboard flooring.

So before i pay someone to lay my expensive new tiles and possibly UFH, what should be done to stop this happening again?

All advice gratefully welcome.

Thanks

[david campbell]

is there any movement in the floor? if not
on top of the first layer of chipboard i would screw 15/18mm ply or use cement boards if there is no movement!

[actionjackson]

is there any movement in the floor? if not
on top of the first layer of chipboard i would screw 15/18mm ply or use cement boards if there is no movement!

how would i tell if their is any movement?

[doug boardley]

same here DC. Why was there another layer of T&G on top of the ply? (which should've been screwed down anyway)

[david campbell]

jump up and down gently on your toes on the floor and if there is any bounce in the floor then it's not suitable for tiling

[Dave]

Hi and welcome..

If the ply is floating then nothing will sort it till this is fixed.. I think there might be a reason for this floor construction.. Are you able to contact the developer.. and ask why..etc..?

[actionjackson]

jump up and down gently on your toes on the floor and if there is any bounce in the floor then it's not suitable for tiling

there appears to be little movement apart from near the walls. When looking under the bath i could see the top plywood and T&G is simply butted up against the stud wall. The stud wall is mounted onto of the actual floor board.

[actionjackson]

Hi and welcome..

If the ply is floating then nothing will sort it till this is fixed.. I think there might be a reason for this floor construction.. Are you able to contact the developer.. and ask why..etc..?

The develops are very difficult to deal with but i can try. I guess this is not a usual layout then? Typical!

[Phil Hobson]

This seems a strange mix to me, in general floating floors and tiles don't go well

[actionjackson]

So would the best course of action be to screw down the 17mm ply to the floorboards?

[Dave]

The develops are very difficult to deal with but i can try. I guess this is not a usual layout then? Typical!

It's not no.. must be a reason why it is laid this way..

[doug boardley]

So would the best course of action be to screw down the 17mm ply to the floorboards?

I'd check with developer first, as Dave says, there must be a reason for it.

[Dave]

So would the best course of action be to screw down the 17mm ply to the floorboards?

In theory yes... but i would double check before you do..

[actionjackson]

Thanks all - i will report back when i have got an answer from ther builders.

[actionjackson]

Right... i have spoken to a very helpful guy at the builders (previous comments taken back lol) and he has told me i have a floating acoustic layer above the T&G chipboard floorboards. This layer consists of 17mm ply, 2mm rubber matting and 17mm T&G chipboard T&which is all bonded as one layer. He did admit this is not the best platform for laying tiles but couldn't offer a solution as this was specified by the developers to reduce sound travel between floors.

So what should i do? Can i simply screw down this acoustic layer and lay tiles on top, accepting i (and my neighbour) will loose the sound proofing properties? Being a bathroom and the floor below having the same layout i can't see this being a major problem.

Just to add to the mix, I'm seriously looking at fitting electric UFH whilst i have the opportunity and would like to know how this fits into the equation.

Thanks in advance.

[DJS]

I'm new to this, so wait for someone with more experience to confirm it.

But if the building requires an acoustic layer, then you can get one's suitable for tiling. The one I seen at my local tile shop display is made by Schluter systems.

If your considering UFH though have you looked at marmox boards?

I had a job recently with similar floor construction. Didn't have a rubber acoustic layer, it was 10mm fibre floating on 25mm ply, overlaid with 22mm chipboard!

To prep the floor I ripped up the T&G chipboard and sound insulation, screwed down the ply on top of the joists (was previously only randomly nailed down, but the floor/joists were solid). I then used 30mm marmox fixed with flexible addy and mechanical fixings, laid a loose wire UFH system, covered in flexible adhesive again and laid a de-coupling membrane, then laid a slate floor on top using flexible addy & grout.

You can get marmox in varying thicknesses, so with a bit of homework, you can work out roughly the right thickness board required to get you back to the original floor level including the new tiles, decoupling membrane and UFH!!

Let us know how you get on

[mikethetile]

if its a conversion then you have a floating floor to deaden sound transfer to the property below

you cant fix it down as it will transfer sound, there are ways around this but your first port of call is the developers as already said

[mikethetile]

I didnt read the 2 page before answering........... oops

but its nice to know I was right LOL

[actionjackson]

if its a conversion then you have a floating floor to deaden sound transfer to the property below

you cant fix it down as it will transfer sound, there are ways around this but your first port of call is the developers as already said

I have spoken to the developers and although they have told me its an floating acoustic overboard floor - im still unsure what i should do to allow me to re tile.

I have just had another look at it and their is also foam underneath the ply.

[Dave]

Use Karndean.. Karndean UK & Ireland Residential | Luxury Vinyl Flooring and Floor Tiles

[actionjackson]

Use Karndean.. Karndean UK & Ireland Residential | Luxury Vinyl Flooring and Floor Tiles

Thats giving in!

[Dave]

i know but problem free..LOL

[actionjackson]

I'm totally worn out with this to be honest and have spent a fair some of money on new tiles already justto rub salt into my wounds lol. You would think that buying a brand new house would be a good move!

[Dave]

Ok OK..

Right.. screw and plug the whole floor down to the slab.. make sure it is solid.. then use an uncoupling membrane.. no probs job done and one tiled floor..

not a cheap route but deffo a good one.

[Dave]

p.s... sorry for avin a laff..

but above method will work if done solidly..

[actionjackson]

Evening all, I have finally got round to booking a week of work to get my bathroom sorted.

DAY 1

was spent removing all of the old tiles - 70% coming up very easily and the remaining being a total nightmare.

This left 18mm water RESISTANT (green) T&G chipboard which was WATER damaged around the bath area.

DAY 2

I decided to remove all the T&G as part was water damaged and i needed to see what was left underneath as i had been told by the builder that i have an acoustic substrate layer.

First i had to use a circular saw to cut around the bath, cupboard, entrance door and then into sections as the T&G was bonded together. Very messy.

This has taken all day and I'm knackered.


full.JPGboard profile.JPGboard.JPGT andG.JPG

As you can see in the pictures I'm left with sections of acoustic panels sitting on top of standard T&G chipboard nailed to the joists. These acoustic panels have a rubber/furry material each side of a 10mm piece of timber (not sure what timber though?) The backing material can easily be pulled away from the boards so my question is -

Can i screw these 10mm wooden panels (unknown material) to the T&G chipboard and then fix my 10mm Marmox tile backer boards with adhesive? Going on top of this is UFH and SLC. The floor is very firm with no notable deflection

I had planned to also tile the walk in (sort of walk-in anyway ) cupboard in the bathroom at a later stage as this houses the water tank and didn't want to be without running water for a week. I'm now wondering if i should leave the white tiles in place and use a strip of timber on the floor to separate the different rooms/tiles. What are peoples experiences with this - will it look rubbish?

open cupboard.JPG

doors.JPG

This is seriously hard work and i have full admiration for you tilers - i do hope I'm over the hard stuff and bring on tomorrow!

[EFC Mike]

Be careful what size screws you use if you go ahead, as the pipes may be high in the floor cavity, which might explain why no fixings in the first instance! It sounds to me like the ply has been glued and failed, maybe?
Good luck!

[Dave]

Looks more like Sound proofing.. Acoustic layer..

[actionjackson]

Be careful what size screws you use if you go ahead, as the pipes may be high in the floor cavity, which might explain why no fixings in the first instance! It sounds to me like the ply has been glued and failed, maybe?
Good luck!

No central heating - only electric so no pipes to worry about. I have been working in my own ceiling void which is 600mm deep and all electrical cables are fixed to the joists about mid-way so should be safe to screw the boards down.

They are deffo acousic boards but i'm unsure what material the wood is?

[actionjackson]

Looks more like Sound proofing.. Acoustic layer..

Yep certainly is. What type of wood do you think it might be going by the pictures?