My pier and beam house moves more than the stock market. I had a foundation repait company give me an estimate, but they said there was no warranty as it would just move again. With a move in the near future, I am wondering if all pier and beam homes are equally succeptible to moving, or if being build in 26' has more to do with it.

I am in the Houston Heights and see giant homes being built in the neighborhood that appear to be pier and beam. Are they using different/better methods? I can't imagine spending a million dollars on a home that needs foundation work on a yearly basis.

And yes, I realize a slab foundation won't have this problem. But I really like the look and feel of pier and beam.

Why is it moving? Is it settling or are you on a fault line?

http://pubs.usgs.gov/sim/2005/2874/pdf/sim2874plate.pdf

Our place is pier and beam and it's stable. There are no signs of movement, ever. IMO it all has to do with your soil and how the footings are constructed. Footings I added are 1' deep x 2'x2'and the originals are the same depth but closer to 1'x2'. Soil in the area is non-expansive.

Seems like you could get a foundation repair company that could insert some new piers that would not move. Or did you just ask them to level your house?
But the answer to your question is yes. It has more to do with construction technique in 1926.

Most large commercial buildings are on piers. They do not move. Need soil borings and an engineer to do it correctly.

[This message has been edited by TexAg2016 (edited 11/14/2013 10:56a).]

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And yes, I realize a slab foundation won't have this problem

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I've actually found the opposite to be true. Slab foundations are generally cheaper to build which is why you see them used in almost all tract homes, while top-notch custom houses will often still use P&B. In my area the expansive clay soil is hellacious on slabs but P&Bs seem to do pretty well if the piers are set down to bedrock. My parent's house which was built in 1955 on P&B is solid, while my 1974 slab construction rocks and rolls...

There is no magic bullet when it comes to the expansive soils we have in Texas. Plenty of WELL DESIGNED slabs out-perform poorly designed pier and beam slabs throughout the state. By the same token, a poorly designed slab can't hold a candle to a well drilled, belled, and designed p&b.

Drilling to an adequate depth should tell you enough about the soil below to tell you which you should use. Also, if you go the slab rout post-tension is the way to go. That is why every builder who does any real volume in Texas uses it.

A newer method is the slabtek method. Basically you pour piers with jacks built into them and then place a post tension slab on top of them. Once the concrete cures jack up the slab 12-18 inches and you have the best of both worlds!

Moral of the story: Ask to find out whether or not an engineer designed the foundation you are looking at and ask around to see how their work holds up in the area.

[This message has been edited by rilloaggie (edited 11/14/2013 12:30p).]

^^ well stated!

+1 rilloaggie

Although I personally wouldn't be buying another slab house on expansive soils in Texas.

We drilled down 6' when we built ours to get through the really bad stuff and still had a little movement. I fixed it myself when we sold the house. When I do it again, I plan on drilling deeper with bellbottoms. The drilling is cheap.

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Also, if you go the slab rout post-tension is the way to go. That is why every builder who does any real volume in Texas uses it.

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NEGATIVE.

Post tensioned slabs are used because they are cheap and fast. No other reason - and don't kid yourself thinking anything otherwise.

If post tensioned was worth a crap, it would be used in something other than residential construction, but it is not (when talking about slab on grades - bridge construction is a completely different story).

To further compound the suckitude that is post tensioned slabs - there is almost zero QC involved with home building. No on site QC slump and temperature tests taken when the truck arrives, no cylinders taken for 7,14 and 28 day compressive strength testing, no QC on proper cure of the concrete, I've not once seen a single mill cert for the wire used in post tensioned, nor reports certifying that the wire was pulled to the proper tension by a certified and calibrated tensioning rig - after verification that the concrete had actually reached design strength on a cylinder test.

Seriously - talk to a contractor or engineer not engaged in the business of throwing up as many homes as humanly possible and you'll find this to be near universally agreed upon.

Slab on grades are just fine - even on Texas gumbo. The problem is that the vast majority (99% or greater) of home builders do dick for work when it comes to subgrade prep, and the codes generally allow them to get away with it. Grubbing the lot does not equate to subgrade prep. 6" of fill brought in from parts unknown does not equate to subgrade prep. And yet, that is the standard for most houses. Overex? Engineered fill? Subgrade compaction to +/- 3% of optimum moisture and 95% standard proctor density? Crap, you might as well be speaking Swahili to your run of the mill home builder when talking about this stuff.

You can have an outstanding SOG with good subgrade prep even in the SOG design is not optimal. You can have the best designed and constructed SOG fail miserably with piss poor subgrade prep.

Drilled piers are still the best way to go, but they come at a cost. It really doesn't matter which slab design you have - if it is not installed properly, it will fail. To what degree and how long is a shot in the dark, but it is still inevitable.

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Post tensioned slabs are used because they are cheap and fast. No other reason - and don't kid yourself thinking anything otherwise.

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Post tension isn't going to work 100% of the time, neither is pier and beam. Post tension slabs are better equipped to handle stresses of expansive soils than conventional rebar slabs simply due to the fact that they are actively reinforcing concrete. You can put the thickest rebar in the world in your slabs but it isn't doing a thing until the concrete starts to fail. 50 years and 300,000 slabs worth of data support this. The fail rate on our post tensioned slabs is about 1/3 of the avg state wide when considering all foundation types including piers.

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If post tensioned was worth a crap, it would be used in something other than residential construction, but it is not (when talking about slab on grades - bridge construction is a completely different story).

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Like High rises?
http://www.vsl.net/Portals/0/vsl_techreports/PT_Buildings.pdf

Or parking garages?
http://www.laytoncompanies.com/parking.html

More?
http://www.adaptsoft.com/resources/CI_article_Oct_2007.pdf

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To further compound the suckitude that is post tensioned slabs - there is almost zero QC involved with home building. No on site QC slump and temperature tests taken when the truck arrives, no cylinders taken for 7,14 and 28 day compressive strength testing, no QC on proper cure of the concrete,

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And this has to do with post tension how? Sounds to me like more of a general qc issue that has nothing to to with pt.

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I've not once seen a single mill cert for the wire used in post tensioned, nor reports certifying that the wire was pulled to the proper tension by a certified and calibrated tensioning rig

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All wire companies that supply cables, anchors, wedges, etc. have to meet pti(post tension institute) specs. All subs that stress and install cables must have their jacks and hydraulics calibrated at least once per 6 months. They do, and I have a stack of calibration forms, along with individual cable observations and measurements sitting in front of me. It would stand to reason that you don't see them because, well, why would you? I don't think you build homes.

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It really doesn't matter which slab design you have - if it is not installed properly, it will fail. To what degree and how long is a shot in the dark, but it is still inevitable.

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Agreed and generally the point I wanted to make in my post. Post tension won't work everywhere(nothing is one size fits all) but to say that it isn't worth a crap is frankly a little foolish. I don't mean anything personal and I'll buy you a beer some day if you want to meet up and talk shop sometime. I just dislike misinformation when it comes to what I do for a living.

Dude, I make a living with concrete. Your arguments are laughable and you are using completely different design parameters when you use parking garages in comparison to homes.

Post tensioned slabs on grade, without the benefit of other systems supporting them, are used on home building because they are fast and cheaper to install when compared to more conventional grade beam slab systems. That is a 100%, undoubtable fact.

They are not used because they are better - in the vast majority of cases, they are not better - they are faster and cheaper, and in an industry that is woefully short on anything remotely considered quality control, faster and cheaper is a good thing for builders and developers.

If you want post tensioned for a slab, have at it. But don't tow a line that is a false line in thinking they are a superior design, because they simply are not - especially when real world variables (such as concrete mix design and placement, mill certs, inspection on tensioning, quality of the cables, calibration of the tensioning machine, skill of the people putting all of this in place, etc) are just as important to a good system as a good design.

And no, I don't build homes. No desire. Been there, done that.

Well, I'm sure you probably know much more about concrete than me, and I'm not being facetious. I know what I need to know about concrete as it pertains to residential const. That is what I know a lot about. I'm not going to be able to change your mind here but I can look at our numbers and tell you without a doubt that pt slabs fail less often than the other options out there. Again, I'd be happy to talk sometime if you want to see it in practice( I think you would be surprised at the level of qc that goes on)