Glue Down Wood Floor Installation:
Site Preparation for Engineered Wood
Flooring
This section, is designed to answer the most common questions
on glue down wood floor installation, as well as outline the
steps necessary to prepare your room for this renovation.
If you wish to nail it down, follow the instructions
for installing a classic 3/4" solid wood floor.
This is not meant to replace a
professional installer, but rather to help our customers understand
the process and guide, those that wish to install the
flooring themselves. Please read carefully all the information
included with your flooring purchase, and follow the manufacturers
recommendations!
Step 1. Preparing The Job Site for an Engineered Wood Floor
What subfloor is considered adequate?
Plywood:
As with standard 3/4" nail down flooring, The National
Hardwood Flooring Association recommends a minimum of 5/8"
tongue and groove plywood as a base. Aspenite or any other
particle board product is not considered to be suitable substitute.
Concrete
Many of these products can and are designed to be glued down
to a concrete base. Check with the individual manufacture
for guidance, and follow specific instructions for moisture
barriers etc. Mirage, will warranty an engineered wood floor,
glued to a concrete slab, as long as there are NOT any related
moisture problems in the concrete, and their recommended
hardwood floor adhesive are used in the installation.
Should I do anything to the subfloor before
I install my Engineered flooring?
Both wood and concrete subfloors should be
tested to see how level they are. Manufacturers typically
require that your floor must be flat to within 3/16"
in 10 feet. High spots must be sanded or ground down and low
spots filled within an appropriate floor leveler (make sure
it is given time to properly dry).
All old flooring must be removed, if it does
not provide a solid gluing surface (or a new subfloor installed
over top).... and the prepared surface must be clean for good
glue adheasion.
Wood Subfloors:
It is essential that a wood subfloor be screwed down every
6" to the underlying floor joists. Once that has been
completed, although it may seem kind of stupid, it is a good
idea to jump around on every corner of the floor, to locate
any remaining squeaks.
Add additional screws and reblock the floor
from underneath in any areas that persist in being noisy.
Don't let anyone convince you that squeaking can be solved
by nailing or glueing a new floor on top. At that point, it
is usually too late to solve the problem!
Concrete Floors:
A conrete floor must be free of grease, oil or dust. If it
has been coated or painted, and you wish to glue your flooring
directly onto the concrete, you may have to wash it with an
acid to etch the concrete, prior to installation. This will
improve the quality of adhesion, between the concrete, glue
and floor. Ask your installer for advice!
All cement floors must be properly dried
(typically 60 to 90 days old for new concrete) before considering
any floor installation.
Test for moisture! Tape a 15" square of clear polethylene plastic to the
concrete slap with moisture resistance tape, sealing the plastic
around all four sides. Leave it for 24-48 hours. If no condensation
collects under the film, then the slab is probably dry enough
to install your floor. Test a number of different locations
around the room and test it in the damp part of the year.
Use heat and fans to speed drying if
necessary, on a new slab.
If this is an older home and moisture problems
are present, DO NOT install wood flooring. The glue will not
hold in most cases and the moisture will get into the wood
and cause all kinds of problems
Below Grade vs At
Grade Concrete Slabs
When a cement slab is located at ground level (at grade),
you don't usually run into problems with moisture, once the
slab has cured properly, and can easily glue this type of
wood flooring directly onto the concrete.
BUT, with the traditional basement floor,
that is lower than the surrounding land (below grade), drainage
around the house becomes a key issue in determining whether
you will have problems. A "wet basement" can exist
"one time of the year" and not another, or "one
year" and not the next..... so be sure that you are comfortable
in saying you DON'T have moisture problems year round before
you invest any dollars in any kind of wood floor.
Plywood laid over
concrete on below grade applications:
If you wish to install a subfloor, over a concrete base, for
insulation or to address minor moisture issues, please see
these web sites from The Hardwood Council and Oak Flooring
Association, for specific advice:
Can I use a glue down wood floor installation
over radiant heat?
Yes, usually, but check with the individual
manufacturer. Most Engineered floors are constructed in layers
to make the product more dimensionally stable (relative to
a solid wood floor). It can withstand minor fluctuations in
temperature, caused by an infloor heating system. Ask First!
Recommendation: stay with the 2 9/16"
wide flooring, avoiding wider planks.
Make sure your radient heat system has been
operating for a number of days prior to installing your floor,
so any residual moisture is removed..... check the moisture
as suggested above.
The fact that it can be glued down, gives
one a degree of comfort in not worrying about putting a nail
through one of your pipes during installation..... but yet
still ending up with a floor that looks exactly like a traditional
3/4" solid wood floor.
There are many different methods of installing
radiant heat systems, both for new homes and to retrofit an
older home. This is beyond the scope of this article, but
let me say this: Most important is to have a system that works
on water volume and low temperature (most new systems).
These low operating temperatures, go a long
ways not to shock your floor and cause any buckling or cupping.
You want a system that maintains a steady even water temperature
with limited radical movement, and then you can glue down
this floor, as you would under any other applications.
For more information try:
The Hardwood Council
Tips on Installing Hardwood Flooring over Radiant Heat
I'm installing this flooring in a new house,
are there any special issues here?
Follow the advice for a traditional wood
floor, get your house to a reasonable humidity (ie under 55%).
All engineered floor is made from natural wood fibres and
will react to excessively high or low moisture levels. If
you follow all these basic guidelines you should have no problem
with your glue down wood floor installation.
Further Information:
Hardwood Floor Installation
Acclimatizing
a Hardwood Floor
