What are the benefits of adding floor insulation or replacing old
- Improved comfort: Floor insulation will help keep the
temperature of your floor closer to the actual room temperature and
will also minimize unwanted drafts coming from the crawl area. It
will also make your home quieter by providing sound control.
- Lower energy costs by keeping the conditioned air in your home
and keeping out the cold moist unconditioned air.
- Reduces the risk of your plumbing pipes freezing
- A well insulated building can improve fire safety by reducing
air leakage that could otherwise provide nourishment to a fire.
Insulation is rated by R value. The higher the number, the more
effective it is in stopping unconditioned air from entering into your
home or heated air from leaving your home.
If you have no insulation at all in your floor and you add R-19 you will
experience a 90% improvement in reducing heat loss. If you already have
R-19 and you upgrade to R-30 you will experience a 36% improvement after
the upgrade. These statistics come from the Clark Public Utilities web
In Washington State the minimum R value in crawl space floor insulation
for new homes is R-30. Many older homes that either donít have any floor
insulation or their existing insulation is old and ineffective will
experience a substantial improvement by adding R-19.
Iíve heard about crawl space encapsulation. Am I better off
sealing the vents to my crawl with a rigid foam board or insulating
between my floor joists and keeping the space ventilated?
If you have or want a non ventilated sealed crawl space, full
encapsulation, then you probably donít need to add floor insulation.
Traditionally, crawl spaces have been vented to prevent problems with
moisture. However there are a growing number of building professionals
that recognize the benefits of a moisture controlled unventilated crawl
There are two main reasons for this line of thinking:
- Ventilation in the winter makes it difficult to keep crawl
- Warm, moist air brought into the crawl space through foundation
vents in the summer is often unable to dehumidify a crawl space. In
fact, this moist outdoor air can lead to increased moisture levels
in the crawl space. This information is from US Dept of Energy
For a more complete discussion on encapsulated crawl spaces please
see our section on crawl spaces
in this website.
Call (253) 691-9239 or
Contact Us for a
free consultation about your crawlspace needs.