Plaster

62tucker

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Pulling my bathroom apart and the outside walls are proving trouble which I thought they would. Plaster is loose in places down to blocks. Thermolite blocks. whats best plaster to use to repair the wall. Bonding in my building site days. It it still the same. It’s about 1/2 inch thick
 

davylad

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I think they use plaster board nowadays, Wise Owl is the man to ask.
 

crackatoa

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Pulling my bathroom apart and the outside walls are proving trouble which I thought they would. Plaster is loose in places down to blocks. Thermolite blocks. whats best plaster to use to repair the wall. Bonding in my building site days. It it still the same. It’s about 1/2 inch thick
It was probably Browning. Best use Sand and Cement to skim finish, or dot and dab plasterboard.
 

62tucker

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It was probably Browning. Best use Sand and Cement to skim finish, or dot and dab plasterboard.
Just be patching the bits that have came off or going to come off.
Internal walls that are boarded have been ok. The 2 layers of tiles that are in them have cane off no problems. It’s just the external walls that have been plastered and skimmed and then 2 layers of tiles.
I thought I would have trouble as I don’t think plaster sticks to thermolite blocks as good as concrete blocks. Or I could be wrong and ordinal plaster just wasn’t put on right.
 

Dave

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Give the Thermolite blocks two coats of diluted PVA first, letting them dry out between coats. And then patch with bonding.
If youre going to retile the walls put the bonding on so it is flush to the finish plaster.

Thermolites suck all the moisture out of the plaster hence the reason to 'size' them first with PVA
 

62tucker

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Give the Thermolite blocks two coats of diluted PVA first, letting them dry out between coats. And then patch with bonding.
If youre going to retile the walls put the bonding on so it is flush to the finish plaster.

Thermolites suck all the moisture out of the plaster hence the reason to 'size' them first with PVA
And just tile straight on top of the bonding ?
Not be me it be a professional fitting my bathroom and tiling.
I have now come across a patch where it’s been boarded to the thermolite and skimmed.
The lad who’s doing job just said if I could remove all old tiles if would be a great help and then he would call in to asses what’s needed plastering wise.
Also pipe dripping leading to my cistern so had to remove that today and stick a bit of wonder tape on and retighten and fingers crossed. Stopped leaking.
If I was more confident I would attempt to do my bathroom myself but scared I balls it up.
New suite. New shower unit etc.
 

slaner

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And just tile straight on top of the bonding ?
Not be me it be a professional fitting my bathroom and tiling.
I have now come across a patch where it’s been boarded to the thermolite and skimmed.
The lad who’s doing job just said if I could remove all old tiles if would be a great help and then he would call in to asses what’s needed plastering wise.
Also pipe dripping leading to my cistern so had to remove that today and stick a bit of wonder tape on and retighten and fingers crossed. Stopped leaking.
If I was more confident I would attempt to do my bathroom myself but scared I balls it up.
New suite. New shower unit etc.
If you are fitting a new bathroom suite etc I wouldn't leave any of that old s**t on the walls and patch it up, hack the lot off and dot n dab some new waterproof boards on, no need to skim just tile straight on, trust me I have done what you are thinking in the past trying to save a few ££s and its bit me in the asse a few years later when the old bonding I left came away from the walls with my new tiles still attached,
 

62tucker

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If you are fitting a new bathroom suite etc I wouldn't leave any of that old s**t on the walls and patch it up, hack the lot off and dot n dab some new waterproof boards on, no need to skim just tile straight on, trust me I have done what you are thinking in the past trying to save a few ££s and its bit me in the asse a few years later when the old bonding I left came away from the walls with my new tiles still attached,
49EF7FC7-2D75-4416-AFF6-4101AD2D3755.jpeg
 

62tucker

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Above the toilet. All external walls down to block.
Might pva and cement joints before boards.
 

Dave

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Definitely PVA, twice, but don't bother cementing the joints, just put your dab on any that look deep and it will give the boards a stronger bond
 

Paul22

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Above the toilet. All external walls down to block.
Might pva and cement joints before boards.
If you are dot and dab the block you will be able to dot straight to the block if you use drywall adhesive......if the blocks are loose they need to be reset properly with sand/cement.
Dot and dab is the easiest and probably cheapest way of doing it.
If you use a moisture board it won’t need skimming and you can tile direct to the board.
British gypsum recommend you don’t skim moisture boards. You can tile any board without skimming but moisture boards are recommended.
Remember a decent tiler will require a decent background to leave you a spot on job.
 

Wise Owl

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Most tilers moan for the sake of moaning ffs it’s only a one piece jigsaw after all said and done ?
 

62tucker

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If you are dot and dab the block you will be able to dot straight to the block if you use drywall adhesive......if the blocks are loose they need to be reset properly with sand/cement.
Dot and dab is the easiest and probably cheapest way of doing it.
If you use a moisture board it won’t need skimming and you can tile direct to the board.
British gypsum recommend you don’t skim moisture boards. You can tile any board without skimming but moisture boards are recommended.
Remember a decent tiler will require a decent background to leave you a spot on job.
The lad who’s doing job said he would send a plasterer to check what needs doing. Also said all loose plaster would have to come off. He originally went around tapping walks so I guess he knew they would be 5hit
 
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