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diy888
Hello, I am a first-time do-it-yourself tiler in the US, though long ago I lived for half a year outside of Bath, in beautiful Somerset. There's lots of good info and many knowledgeable folk on this site, and I need your advice on a particular problem. I'm using wedi, and I think wedi is more widely used in the UK and Europe than it is here in the States.
I am using a wedi presloped Fundo shower base. I bought 50mm mosaics (2" x 2") and quite a bit of matching quarter-cove trim pieces, which are non-returnable. It turns out the mosaics are thinner than advertised, 4mm rather than 6mm. 6mm would have been perfect for the wedi base; but 4mm creates a problem. The 2mm difference looks small but there's more to it than meets the eye.
The plastic strainer frame on the particular wedi drain that shipped with my unit rises about 9-10mm above the cementitious surface; in order to have the mosaic tile be flush with the top of the drain, a ~6mm-thick adhesive bed would have to be placed under the mosaic tile.
The manufacturer of the thinset I bought says their thinset would lose much of its compressive strength if laid so thickly, especially beneath small tiles. The 100% solids epoxy mortar I bought from another manufacturer can't go thicker than 3mm beneath the tile either.
Why am I concerned about compressive strength? A former wedi distributor in the US told me that they didn't recommend tiles smaller than 4 inches when wedi is used underfoot, and I recalled a wedi recommendation to use epoxy with mosaics. So I'm taking the point-load issue seriously, even though on another tiling forum people told me not to worry, unless I happened to weigh 20 stone.
To build the surface up, I've put down a layer of thinset down on the wedi Fundo base, combing it with a 3mm U-notch trowel. It has cured for several days. Now I want to fill in the valleys to create a smooth surface for the final mortar bed to go on top of. Can I use epoxy mortar to fill in the valleys, let it cure, and then bed the mosaics in another layer of epoxy mortar? Or should I use thinset again to fill the valleys, and only use the epoxy as the final bedding layer? Is it 6 of one, half a dozen of the other?
Thanks
Tim
I am using a wedi presloped Fundo shower base. I bought 50mm mosaics (2" x 2") and quite a bit of matching quarter-cove trim pieces, which are non-returnable. It turns out the mosaics are thinner than advertised, 4mm rather than 6mm. 6mm would have been perfect for the wedi base; but 4mm creates a problem. The 2mm difference looks small but there's more to it than meets the eye.
The plastic strainer frame on the particular wedi drain that shipped with my unit rises about 9-10mm above the cementitious surface; in order to have the mosaic tile be flush with the top of the drain, a ~6mm-thick adhesive bed would have to be placed under the mosaic tile.
The manufacturer of the thinset I bought says their thinset would lose much of its compressive strength if laid so thickly, especially beneath small tiles. The 100% solids epoxy mortar I bought from another manufacturer can't go thicker than 3mm beneath the tile either.
Why am I concerned about compressive strength? A former wedi distributor in the US told me that they didn't recommend tiles smaller than 4 inches when wedi is used underfoot, and I recalled a wedi recommendation to use epoxy with mosaics. So I'm taking the point-load issue seriously, even though on another tiling forum people told me not to worry, unless I happened to weigh 20 stone.
To build the surface up, I've put down a layer of thinset down on the wedi Fundo base, combing it with a 3mm U-notch trowel. It has cured for several days. Now I want to fill in the valleys to create a smooth surface for the final mortar bed to go on top of. Can I use epoxy mortar to fill in the valleys, let it cure, and then bed the mosaics in another layer of epoxy mortar? Or should I use thinset again to fill the valleys, and only use the epoxy as the final bedding layer? Is it 6 of one, half a dozen of the other?
Thanks
Tim
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