One of the most
misunderstood sections of a home is the crawl space. Many homeowners take this
for granted or do they understand what crawl spaces are and how it can benefit
a home. Homeowners accept the fact that these crawl spaces are there in their
homes for lack of a basement. However,
there is more to crawl spaces than meets the eye.
To answer how critical
it is to maintain a good condition for crawl spaces and what homeowners can do
to improve this condition, first, people must understand what crawl spaces are
meant for.
What is a Crawl Space?
Technically, a crawl
space is a variation or an alternative to a basement, particularly for homes
located in areas where basements are not practical to build. Unlike a basement
which is practically another level to a home, the gaps inside crawl spaces are
just large enough to crawl into, thus the name. For houses that are not built
on solid rock or slabs, the surface of crawl spaces is plain bare earth. The
original purpose of crawl spaces is to create a certain gap between the floor
and the ground as an access area for the maintenance and repair of household
facilities like electrical wirings and plumbing works. Pipes and other
substructures can be easily accessed through crawl spaces.
Another purpose for
crawl spaces is to provide a passageway for cooling air to circulate all
throughout the house. However, this reason is the main cause for the
accumulation of moisture inside this area, on top of the already damp soil and
moisture that seeps through the permeable surface of the concrete walls. Aside
from the small space inside that makes crawl spaces an impossible location for
a living space, moisture would be the main reason why crawl spaces is not an
ideal location for storage of seldom-used items inside the home. Although many
homeowners do use crawl spaces as storage areas, the inherent moisture in these
areas can make it susceptible to the proliferation of molds and mildew which
can attack anything organic. Paper, cardboard, wood, cloth and other similar
materials are organic and can be affected with molds if exposed to moisture.
Types of Crawl Spaces
and Their Characteristics
Houses with crawl spaces
have been designed and built throughout the years based on two building
methods. The following discusses these types and the typical characteristics
that homeowners will encounter with each type.
* Vented Crawl Spaces
For several years, the
International Residential Code has mandated that crawl spaces should have
ventilation leading into the exterior. The purpose of these vents supposedly is
to bring in fresh air from the environment and to be circulated around the home.
The belief that venting can remove moisture from crawl spaces slowly diminished
through the years as homes continued to experience the proliferation of molds,
mildew, termites and other pests, which slowly caused a slow decay to the
foundation of the house.
This problem persisted
for years and the initial solution that builders thought of was to increase the
ventilation. Homes with central air conditioning had their ductworks installed
within these crawl spaces allowing better circulation of air. Still, the
problems with moisture and its related issues persisted.
A better understanding
of how crawl spaces and ductwork function showed that venting is not effective
in minimizing moisture within crawl spaces. Condensation should be taken into
account, particularly if the outside air is hotter than the air inside. As hot
air enters these vents and ducts and comes into contact with colder surface,
the air reaches dew point and creates condensation. And when there is
condensation, there is moisture.
Another problem seen
with vented crawl spaces is that it could be the vehicle for disease to spread
throughout the house. Moist crawl spaces would only result to mold and mildew
infestation, as well as the proliferation of other disease-carrying pests. Air
from these crawl spaces is then circulated into the home, along with harmful
pathogens that would put the residents at risks.
* Dirt Crawl Spaces
Traditionally, crawl
spaces are built as part of the foundation of a home but most are built with
the bare earth as the base. This exposure to soil can result to a very high humidity
level and this moisture is then allowed to circulate into the home.
As mentioned earlier,
people tend to utilize crawl spaces as storage areas for a variety of stuff.
However, the inherent moisture content of these crawl spaces makes it susceptible
for mold growth. The moisture level is further aggravated when homeowners use
crawl spaces as an area where clothes dryers are vented into. The design and
structure of crawl spaces, where most lacks an effective insulation layer or a
moisture barrier, also contributes to these high humidity levels.
The Dangers Associated
with Moisture in Crawl Spaces
Crawl spaces, particular
those built on bare ground due to cost considerations are prone to moisture and
high humidity levels. This condition creates the following potential health and
even economic implications, which homeowners should seriously take into
consideration.
* Molds, Mildew and
Fungi
Molds and other
microorganisms thrive on organic materials that are exposed to moisture and
located in damp and dark areas. It has been proven that molds can cause certain
diseases that if left unchecked can cause more health risk implications.
Another potential problem is that spores coming from molds in crawl spaces can
spread throughout the house as they are carried within the circulated air in
vents and ductworks.
* Wood Rot
Microorganisms that
cause wood to rot proliferate in the same manner as molds and mildew. The
biggest problem is that the wood located in the foundations of the home are the
ones being attacked by these microorganism. Repair or replacement would be a
very costly affair because the house itself is built on top of this foundation.
* Damage to Belongings
As mentioned earlier,
organic materials that are stored inside crawl spaces are prone to infestation
by molds and mildew. If left unabated, these materials would slowly rot away
and rendered unusable.
* Increased Relative
Humidity resulting to Increased Energy Costs
As explained earlier,
vents actually increases relative humidity inside the home, resulting in
condensation on pipes and ductworks. This would result to an increase in
overall energy costs due to the adjustments made by your air conditioning and
heating equipment due to the cold air coming in during winter and the hot air
entering the house during summer.
* Standing Water
One of the perennial
problems of dirt crawl spaces is standing water caused by moisture from the
soil, moisture from seepages in the concrete and condensation from the
ventilated air. Standing water can result to unpleasant odor that can circulate
throughout the house, as well as disease causing bacteria.
* Household Pests
Most pests like
termites, rats and cockroaches thrive in damp and dark places. Your crawl
spaces are likely candidates for their abode and pest infestation can lead to
other health risks.
Improving the Condition
of Your Crawl Spaces
The perennial problem of
moisture in crawl spaces resulted in a variety of attempts for remediation,
which includes the pouring of concrete. However, the problem with this remedy
is the high costs and the difficulty of pouring concrete into an already built
foundation and floor. Another problem that would be encountered would be on how
to address the permeating moisture that seeps through the walls and accumulates
into the crawl spaces. Another method should be performed to address this.
In this regard, the
following procedures are outlined in an attempt to provide a guide on how to
remedy this moisture problem and improve the conditions of crawl spaces.
1st Step: The Removal of
Organic Debris
Begin by removing scraps
of wood and other organic materials from the crawl space flooring. These
materials should be removed before any insulation is laid out on the floor to
eliminate any potential "food" for molds and other microorganisms.
2nd Step: Remedy the
Issue on Standing Water
Any insulation work to
crawl spaces would be for naught if standing water is not remedied. There are
advances drainage enhancement methods available that can readily remove standing
water inside crawl spaces. These methods are customized though per home as each
home has its unique drainage characteristics.
3rd Step: Installation
of a Vapor Barrier
Using advanced plastic
liners, the floors and walls of the crawl space should be completely sealed.
Caulking should be done when the plastic liner encounters pipes and other
protrusions. The plastic liner should be at least 20-mil thick and made from
sandwiched layers of high and low density polyethylene.
4th Step: Cover and Seal
the Vents
As explained earlier,
vents are not effective in removing moisture and could actually increase it. It
can also lead to energy wastes. Seal and cover these vents using the plastic
lines can caulking as necessary.
5th Step: Install a
Dehumidifier
To completely dry a
crawl space before sealing it, you must first use a dehumidifier to speed up
the removal of moisture from the compartment.
6th Step: Prop Up
Sagging Floors
Sagging floors can
result from the moisture accumulation that weakens the wooden structural beams
causing it to sage from the weight exerted by the house. For severe cases, you
may need to prop them up using adjustable jacks which can be adjusted should
the need arises in the future.
Crawl spaces are
important sections of the house that if not well attended to, could result to
serious structural risk as well as health risks to the occupants of the house. Changing
the way how crawl spaces were installed or built can improve its conditions and
make it safer and more reliable.
