es, Hardwood flooring can be installed successfully over a
slab which is on-grade or above grade. Below-grade
installations are not recommended. The slab must be
constructed properly (dry and flat with a trowel finish).
Watch out for water. New concrete is heavy with
moisture, an inherent enemy of wood. Proper on-grade
slab construction requires a vapor retarder such as 6
mil polyethylene film between the gravel fill and the
slab.
While this prevents moisture entry through the
slab, this membrane also retards curing of the slab. So
test for dryness, even if the slab has been in place over
two years. Slabs younger than 60-days are generally
too wet for flooring installation.
es, Hardwood flooring can be installed successfully over a
slab which is on-grade or above grade. Below-grade
installations are not recommended. The slab must be
constructed properly (dry and flat with a trowel finish).
Watch out for water. New concrete is heavy with
moisture, an inherent enemy of wood. Proper on-grade
slab construction requires a vapor retarder such as 6
mil polyethylene film between the gravel fill and the
slab.
While this prevents moisture entry through the
slab, this membrane also retards curing of the slab. So
test for dryness, even if the slab has been in place over
two years. Slabs younger than 60-days are generally
too wet for flooring installation.
