Hardwood Floor Underlayment? Yes or No
NOTE: this is Not a discussion of underlay required for "floating
floors" but rather only in reference to installing nail down
solid hardwood flooring!
Do I need to put tar paper or wax paper over my subfloor before
traditional installation of hardwood flooring? The answer is NO!
At least not under normal conditions.
This is probably a question I get asked every week by various
home owners that are interesting in installing their own hardwood
flooring. Let me suggest first and foremost that felt paper does
NOT stop squeaks! It seems to me that this is the most common
consumer understanding on why paper is used when installing hardwood
flooring, but I'll discuss that a little more, further down the
So then the obvious question, considering that we KNOW installers
have been using felt paper under hardwood flooring for many years,
is why did they do it? Well, I have asked every installer I have
come in contact with for the last 20 years and here's their most
- the tar paper prevents moisture migrating from a damp basement
up into the underside of hardwood flooring... but how many people
have a damp basement today?
In older days, the basement was an infrequently used crawl space
with only a earth base, so moisture was an issue... today the
basement is usually a fully finished living space with the same
environmental conditions as the rest of the house... sooo there
is no moisture to keep out of the flooring
If you are installing flooring above a damp crawl space then
certainly using tar paper as a moisture barrier is a great idea.
But maybe a better idea is to consider other flooring options
that are more able to deal with high moisture conditions.
- In the old days subfloors were traditionally made of rough
lumber. Installation of hardwood flooring using wax paper was
common, to prevent the slivers from the rough lumber getting
caught between the tongue and groove connection of the neighbourhood
boards of hardwood flooring. If a sliver of wood got caught
between the boards then it would leave cracks and make wood
floor installation more difficult.
Today we always use oriented strand board (OSB) or plywood as
the subfloor so dealing with the fibers of rough lumber is rarely
an issue... and NOT a reason to use a hardwood floor underlayment
or wax paper.
As pointed out earlier, many suggest that we should install felt
paper to stop squeaks--- Felt Paper does not stop squeaks--- usually
squeaks are caused by
1. subfloor (plywood) movement against floor joists (especially
in cases where bracing has been removed to install air ducting)
2. strips of hardwood flooring moving against each other, particularly
when nails have been spaced too far apart or tongues broken during
Felt paper will NOT help either of these conditions.
Thus make a decision that makes sense given your particular job
site issues and don't work under the illusion that underlay paper
is an easy solution to moisture migration or squeaking in hardwood
flooring installation. If you want to use it, go for it. Its not
expensive. But deal with squeaking and moisture as separate issues.
As a last point, I really don't like using tar paper as a hardwood
floor underlayment under any conditions as my personal hangup
is that it adds toxins to the home environment that I don't want
to breath. If its not necessary then why expose your body to this
Hardwood Floor Installation