Abstract = Experience
shows that a high moisture content in concrete slabs at the time floor
coverings are laid often increases emission of volatile organic compounds
(VOC) from the floor. In this study the emission of VOCs was measured from
floor constructions with concrete, adhesive and vinyl flooring. Concrete
with different water-to-cement ratios was placed in cups. A levelling compound
of low alkali content was applied to some of the specimens. The concrete
was left to dry for varying periods before the vinyl flooring was laid
in order to obtain different moisture contents. The emission of VOCs from
the floor specimens was measured by a Field and Laboratory Emission Cell
(FLEC). The results show that the emission of VOCs increases from floors
with high moisture content. However, the emission from the floors where
the concrete has a low water-to-cement ratio also increases even if the
moisture content is low. This probably an effect of the higher content
of alkali in this concrete composition. A levelling compound decreases
the emission when the underlying concrete has a low water-to-cement ratio.
This effect was not obtained when the underlying concrete had a higher
moisture content. The conclusion is that it is both important to let the
concrete dry sufficiently before applying the floor covering and to the
alkali content of the material, concrete or a levelling compound, directly
beneath the vinyl flooring. |