Before we lay the timber or floating floor, we need to know if the moisture content of the sub floor is suitable for flooring.

There are basically three methods: Preliminary test, Electrical resistance test and Hygrometer test. Both Electrical resistance test and Hygrometer test need expensive equipment to do the tests. Here we’d like to introduce the preliminary test,which is the easiest way. Anyone can do it.

A piece of impervious material such as polyethylene or vinyl sheeting (at least 600×600 mm). It is placed on the surface of the concrete slab to be tested and sealed through around all edges with moisture free sealing compounds. After a period of not less than 24 hours, the covered portion of the concrete slab is inspected for dampness. If this area is even slightly darker in colour than the remainder of the slab, the sub floor shall be considered too wet. Otherwise, it is dry sufficiently to lay floor on.

Thanks
Steven X. Chen