| Copyright © 2008 Christopher R. Prickett. All rights reserved worldwide |
| Expansive Soil |
If you are reading this, there is a very good chance that YOU HAVE EXPANSIVE SOIL!
Here’s a map that can illustrate point: GREATER PHOENIX/TUCSON SHRINK/SWELL
MAPS
So, what the heck is expansive soil? Well, it's fine grained clay which is found in many
areas throughout the Valley and it has the potential to cost you thousands in damage.
Do I have your attention?
As water is initially introduced into the soil (by rainfall or over-watering), the soil swells
like a sponge. If dried out, the soil will contract. This excessive wetting and/or drying
can result in damage due to differential settling of your foundation, driveway, patios and
walkways, and pool. Once damage occurs, the repairs are costly and extensive!
Here are five tips that can help minimize the detrimental effect of the expansive soil on
your home. If you are a landlord, you might want to share these tips with your tenant.
1. Proper drainage after a rain is the most important single factor. Rainfall should
run off the property as fast as possible following a storm. About an hour or two after the
next storm you should inspect your yard for "ponding", especially next to the building. If
you have ponding, the lot drainage should be improved as soon as practical, as
ponding water could saturate the foundation and cause major structural damage. Re-
grading of the lot and/or installation of a drainage system may be necessary to alleviate
the drainage problem.
2. Installation of rain gutters and downspouts can help in the elimination of a
drainage problem, but be sure that the downspout outlet does not discharge close to
the structure, as this could cause a problem.
3. In the summer water your lawn lightly two or three times a week. Heavy watering
is not recommended as this could saturate the foundations. However, it should be
emphasized that a uniform moisture condition around foundations should be maintained
throughout the year. This will prevent periodic drying (shrinkage) and wetting
(expansion) which will cause damage to structures.
4. Monitor your water consumption. An unexplained increase in your water bill
could indicate a plumbing leak. If there's a leak, call a plumber!
5. Don't plant trees, even small ones, within 10' of the house. Trees tend to extract
moisture from soil causing shrinkage. Greater separation is appropriate for larger trees.
Plants that require a large amount of moisture are also not recommended near
buildings.
If you think you 're having a problem with expansive soil, it would be in your best
interest to contact a soil engineer who specializes in expansive soil problems. If you
wish, you may contact the County Building Department for a list of soil engineers who
have analyzed expansive soil problems in your area. A soil engineer can investigate the
problem and make specific recommendations for elimination of the problem and repair
of your home.
Here’s a map that can illustrate point: GREATER PHOENIX/TUCSON SHRINK/SWELL
MAPS
So, what the heck is expansive soil? Well, it's fine grained clay which is found in many
areas throughout the Valley and it has the potential to cost you thousands in damage.
Do I have your attention?
As water is initially introduced into the soil (by rainfall or over-watering), the soil swells
like a sponge. If dried out, the soil will contract. This excessive wetting and/or drying
can result in damage due to differential settling of your foundation, driveway, patios and
walkways, and pool. Once damage occurs, the repairs are costly and extensive!
Here are five tips that can help minimize the detrimental effect of the expansive soil on
your home. If you are a landlord, you might want to share these tips with your tenant.
1. Proper drainage after a rain is the most important single factor. Rainfall should
run off the property as fast as possible following a storm. About an hour or two after the
next storm you should inspect your yard for "ponding", especially next to the building. If
you have ponding, the lot drainage should be improved as soon as practical, as
ponding water could saturate the foundation and cause major structural damage. Re-
grading of the lot and/or installation of a drainage system may be necessary to alleviate
the drainage problem.
2. Installation of rain gutters and downspouts can help in the elimination of a
drainage problem, but be sure that the downspout outlet does not discharge close to
the structure, as this could cause a problem.
3. In the summer water your lawn lightly two or three times a week. Heavy watering
is not recommended as this could saturate the foundations. However, it should be
emphasized that a uniform moisture condition around foundations should be maintained
throughout the year. This will prevent periodic drying (shrinkage) and wetting
(expansion) which will cause damage to structures.
4. Monitor your water consumption. An unexplained increase in your water bill
could indicate a plumbing leak. If there's a leak, call a plumber!
5. Don't plant trees, even small ones, within 10' of the house. Trees tend to extract
moisture from soil causing shrinkage. Greater separation is appropriate for larger trees.
Plants that require a large amount of moisture are also not recommended near
buildings.
If you think you 're having a problem with expansive soil, it would be in your best
interest to contact a soil engineer who specializes in expansive soil problems. If you
wish, you may contact the County Building Department for a list of soil engineers who
have analyzed expansive soil problems in your area. A soil engineer can investigate the
problem and make specific recommendations for elimination of the problem and repair
of your home.