Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 22·5.6
Membrane above concrete - polyethylene or bitumen solution
A membrane laid above the concrete can be polyethylene sheet or three coats of cold applied bitumen solution or similar material, and must be protected by a screed or floor finish unless it serves as a waterproof floor finish itself.
A membrane laid above the concrete should be either polyethylene sheet as described above (but without the bedding material) or three coats of cold applied bitumen solution or similar moisture and water vapour resisting material. In each case it should be protected either by a screed or a floor finish, unless it is a waterproof membrane that will also serve as a floor finish.
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