How common are foundation issues? (Houston: sales, how much, houses)

[Hopeful for Life]

I often hear that these issues happen because of the type of soil that we have here. Has it happened to you?

[mkwensky]

Very common. I had them in three different houses in different parts of town.
You should almost accept this as a given when you buy in the area.

[As Above So Below...]

Very common. I dont know anyone who hasnt had them.

[Need4Camaro]

How are foundation issues generally handled? How far can they go before they need to be repaired and how are they repaired? does it require a teardown / rebuild?

[elnina]

Very common, due to expansive soil.
Look at the maps:

https://www.stratumfoundationrepair....D3XdypECg.jpeg
https://www.permapier.com/wp-content...-experts-1.jpg

Depending on damage and method, here is general estimate:
https://homeguide.com/costs/foundation-repair-cost

Watering the foundation might help. I am looking into it myself.
https://hdfoundationrepair.com/how-o...my-foundation/

[astrohip]

While foundation problems are common, not all houses have them. Most builders use post-tensioned slabs, and they can be prone to shifting (cracking) over time. Much depends on the soil, the soil prep, and the quality of the slab. And PTS are the cheapest slabs a builder can choose.

We had a house built in 1988, and the builder used bell-bottom piers with beams, and a floating slab. Never had a problem in 30 years (we sold it in 2018). Not a crack in the wall, never even a door shift. I had an appraiser run a water level and he said it wasn't 1/16" out of level, front to back, over almost 100 feet. Not bad for 30 years!

So better slabs are available, but most people don't want to pay for them. My attitude was I'm either going to pay for it now, or pay for it later. I chose now.

[Ghost Town]

I hear that there have to be sprinklers around the house to prevent foundation cracks. But I bought the house built in early 90s without any sprinklers and I don't see any issues so far. Half of my neighbors also don't have sprinklers. Maybe these houses were built better back then.

[modster]

It's almost a given that slab on grade foundations in Houston will need some kind of work at some point. This is due to the "gumbo soil" we have here. The clay soil expands in wet weather and can contract considerably during very hot, dry spells. This movement can spell trouble for foundations. Another common culprit for foundation problems is failure of the under-slab sewer lines. Houses built in the 50's and 60's usually had cast iron sewer lines that ran under the slab, buried in the ground. These lines typically had a 40 - 50 year life span before turning into Swiss cheese and leaking. In more severe failures, some sections of the pipe could completely disintegrate, and when water would be carried down the pipes, it would wash out some of the clay soil underneath the slab, and over time cause the house to sink in those places. If you ever are house shopping mid-century fixer uppers, estate sales and the like, you may often see sheetrock cracks and settlement in and around master bathrooms and utility rooms for this reason. Under slab plumbing reroute is not a cheap date.

As for repairs, there are a ton of foundation companies out there, and some are definitely better than others. Reputable ones offer a lifetime transferable warranty on their work. The "work" typically consists of installing underground piers that basically jack up the house. The most common foundation issues involve "drooping" around the edges, requiring exterior piers installed around the outside perimeter of the house. If there is settlement in the interior, then more expensive interior piers are required. There are three common methods to deal with this. With piers, they either break through the slab, punching a hole in it to install the piers, then cementing it back up, or the more expensive tunneling method, tunneling under the house. If it is paired with replacement of the under-slab plumbing at the same time, tunneling may be the way to go. The third option I am not as familiar with, but there's a way they can drill dime size holes in the slab and inject a substance the lifts the slab. Only a few companies are capable of doing that, and those that don't are quick to criticize the method. How much of that criticism is due to they don't sell it and how much is due to actual shortcomings is up for debate. It's my understanding though that it's been used on commercial properties for years. Only more recently has it moved into the residential market.

Determining if a house actually needs foundation work is best determined by a structural engineer. You can get a free estimate and opinion from a foundation company, and some are more honest than others, but at the end of the day they are in the business of selling piers, so you are better off getting a determination from an engineer. Typically they measure the deflection in the slab, it's never 100% level from the day they were built. They usually allow up to 2 inches of deflection over so many yards, I can't remember how many yards though.

I've seen this movie a few times....