Foundation for Clay Soil

[Susan]

Hi guys! We have ordered our Keystone home by PH. Only thing we still cannot decide on is wheter or not to have the concrete runners poured for a foundation or just leave it on the standard blocks.

It will be placed on clay soil in the Central TX area, w/a little sand in the area, but mostly red clay. It will have a perimeter to support the 2x6 exterior walls, but we will not have sheetrock. (May upgrade that ourselves someday)

It's a pretty big expense (around $3000), that we have no idea if it's worth that. From what we've heard the house should be pretty sturdy on that type of soil, but if the expense will save us money down the road and take away the "spring" you typically get when walking across a mobile home floor, it would be woth it.

HELP!!!

Any suggestions would be greatly appreciated!!

Susan

[Susan]

Forgot to add...we don't have to worry about resale value, this is going on family land, so resale value isn't a big issue.

[rmurray]

Actually the set up manual should prevail...the only real way to know what you really need is to do a soil compression test..then refer to the manual for proper instructions..

Soil compression test are not hard to do..nor are they very expensive..

[Danny]

I am a manuactured housing cotractor in North Carolina where theres mostly clay in this area....a home on clay will settle ... I would recommend poured footings no matter what...

[Craig]

I just ordered a Homes of Merit & will be putting it in NE FL.
I am having it put on concrete runners. for the $3000, its worth the peice of mind to me to decrease my chance of problems.

[Rschmitt]

I'm not familiar with the soils in that area, but here in CA clay soils are very expansive, that is they swell with the rains and dry out and crack apart when dry after the rainy season. This can cause lots of problems. Additionally, it can cause moisture problems under the home. We set all our homes on concrete perimeter stem wall foundations and in these situations will dig the footings at least 18" deep into the soil which helps with both problems. A local soils engineer could probably give you some great advice in about 10 minutes time.

[Russ]

I too am a General Contractor in AZ and yes, clay soil is the worst. Biggest thing to do in this situation is to make sure water sheds away from the home and does not collect near or under the home.

Concrete runners are definately worth the expense but usually these are fairly shallow, usually 6 to 8 inches of concrete and definately not below any frost line.

My advice would be to go with as permanent foundation as can be afforded and make sure concrete is poured as thick and high strength (3000PSI vs 2500PSI) and can be had. Also make sure steel reinforcement is used.

Especially on the water issue...no home will withstand water collecting around its foundation for long durations. if you keep water away you will be better off. Have your site sloped away from the home in all directions.