Expansive clay soil construction questions

[DUCK01]

I'm in the quote stage of having a new pool installed and have concerns regarding our soil type. I'm in a small sliver of SE Texas that has clay soil. It swells in the wet season and cracks in the Summer. I've seen cracks that are 2" wide and over a foot deep in my yard and I've been in the place less than a year.

The closest pool builders to me are in College Station and NE Houston, but the soils in both locations are very different than our property, in that they're loamy to sandy loam. The area I'm in is very rural (my town's population is ~250) and I only know of one other in-ground pool in the area. I'm guessing it's ~20 years old - the pool needs some TLC, but is solid. The flatwork is a different story, as it has shifted quite a bit over time. No idea who originally built it.

Our soil is much more similar to the Dallas / Fort Worth area and am wondering if anyone from that area can offer up their experience. I've read about chemically injecting the soil to keep it from absorbing water and expanding. There may be other options, but I want to be able to ask the right questions and know if I'm getting a legitimate answer or not. The first company I had come out couldn't offer up a solution and even said that they had one pool with flatwork cracking & shifting that they couldn't resolve. They're obviously off my list for consideration, now.

Thanks for anything that can be shared.

 

[YippeeSkippy]

Another option is to place small sprinklers in the ground around the pool to keep the soil evenly moist, if I recall?

Let me page a couple of our Texas folks for input --> @pooldv @Jimrahbe @JJ_Tex @Texas Splash

Maddie

 

[Jimmie48]

DFW pool in progress here with very clay rich soil in my yard. We did the injections as a precaution even though most are not doing it around here, as we are on a greenbelt where we get a lot of water when it rains. We also had a sump put in under the pool which our PB told us they rarely ever have to use just as a precaution. We did have some recommend piers but the engineer we talked to said they are only as good as the ground underneath them....meaning they can shift as well. If you do piers do standard concrete piers not helical metal piers....according to our engineer. Have you had a soil test done? See how deep your bedrock is also, it may be higher than you think. Just giving you my 2 cents.

 

[rmontgomery]

I just had mine built East of Dallas and spent many days concerned with the soil preparation decision. The pool builder indicated probably more than 95% do not do anything in our area and they have not had issues or known of issues over the past many years he has been building pools. Even if I were to do injections or piers, they would still not warranty it without an engineering report. So scoured the internet and forums for recommendations. What I found was that the best thing you can do is what Maddie describes so I had sprinkler guys install a drip system around the pool. From what I understand even with piers or injections, the soil will still move and the only way to help prevent it is to keep the soil at an even moisture. I also had the pool builder up the rebar to #4 and he placed them on 6" centers, which is probably way overkill, but it was only a couple hundred dollars more for the false sense of security.

 

[JJ_Tex]

We hired an engineer for about $1k. It was not so much for the clay/soil, but due to the fact that we sit on top of a 15' retaining wall and didnt want our pool to end up in our neighbor's yard.

He recommended piers and soil injections. Luckily during our construction when they added the piers, we were only a few feet off the bedrock. The engineer was able to modify the design to half the amount of piers and no soil injections.

Good luck. Also, there is plenty of clay in Houston so a builder there should be very familiar with building in clay.

 

[DUCK01]

Thanks, all. Good call on a soil test. I can do that independent of the pool process and have those results in my back pocket, whether we decide to start this year or next. I'd thought about adding drip irrigation around our house to keep it level (102yo pier and beam), I could do the same around the pool. Coupled with more steel, I'd at least have a fighting chance. Instead of trying to keep the pool from moving with the soil, you just minimize the soil movement.