Amtico floor failure - advice required

Because it's a separate physical barrier as opposed to a bonded chemical barrier. Same as a screw is a mechanical fixing, and glue is chemical.

 

I always thought it was reffered to as a mechanical dpm as it is part of the structural part of the house and also to distinguish it between a flooring liquid dpm, that and it sounds mighty fancy when explaining to a customer what one is

 

It's just a terminology thing, you know how the construction industry is. Trades call it one or more thing frequently depending on what area you're in, manufacturers another and building regs another. Personally I don't see the problem with calling it a DPM and liquid DPM.

I suppose as long as it's called something other than a sheet of plastic and a tin of paint it sounds better.

 

I agree, it's terminology. I'm just a bit of a technocrat and had not heard of it described that way previously. A flooring, surface applied membrane, actually uses a mechanical bond to hold on to a substrate, which is why you need to give the substrate a key - shot blasting, grinding or abrading but it's called a surface applied membrane. I was not sure if this is what the previous writer meant. Polythene/Visqueen is normally described as a structural membrane.

 

It's technical nit picking for sure, but the surface applied/liquid membrane are chemical bond not mechanical, the bonding and capillary action keep it in place. Polythene membranes aren't structural as they are held in place by the structure (concrete, mortar, screed insulation) but don't actually form part of the structure.

 

Thanks for that. It was previously explained to me that 2-component surface applied, liquid membranes were chemical cure and mechanically bonded, as was the Visqueen/Polythene scenario.

 

It's just the same as calling screws or nails mechanical fixings. It's physically solid as opposed to the chemical ie liquid adhesive or dpm.

 

Have you had issues with this company?