Just a thought: cost differences in post & pier / monolithic slab

[SardonicSmile]

After a lot of research (and building my own house), I've convinced that slab foundations are just as cheap or cheaper than post & pier if you stain/paint the slab.. atleast here in the southern United States. In colder climates, slab foundations become more expensive and complicated.

Examples based on 30x20' 1/2

Slab:
$250 Backhoe rental.
$1500 Concrete for 4" monolithic slab, priced around $100 a yard.
$500 Labor, because a monolithic slab can be difficult to be set up on your own.
$500 Misc: slab screen, rebar, plastic, etc..
$200 If you use the expensive stain kits/solutions

Comes out to less than $3000, and no need for flooring of any kind.


Here are some REALISTIC examples of some DIY stained slabs..

[Beavers]

I totally agree with you if you are comparing concrete piers to a concrete slab.  The slab wins hands down, even a concrete block crawlspace wins out in some situations.   
With the slab or crawlspace you don't have to deal with bracing piers, insulating the floor, or plumbing, building beams, and buying pier to beam brackets.  All that adds up to $$$

If you are talking wood piers though...I'm still convinced that they are the cheapest easiest to build foundation out there.  They are easy to brace and attach a beam to.  If you are cool with the fact the wood isn't going to last as long as concrete, when in direct contact with the ground. 
If you are looking for cheap and easy they are the best IMHO! 

I've done a wood pier foundation and most of a concrete pier foundation.  I would do a wood pier foundation again, but agree that there are better options (time and money wise) than a concrete pier foundation.

[SardonicSmile]

I totally agree with you if you are comparing concrete piers to a concrete slab.  The slab wins hands down, even a concrete block crawlspace wins out in some situations.   
With the slab or crawlspace you don't have to deal with bracing piers, insulating the floor, or plumbing, building beams, and buying pier to beam brackets.  All that adds up to $$$

If you are talking wood piers though...I'm still convinced that they are the cheapest easiest to build foundation out there.  They are easy to brace and attach a beam to.  If you are cool with the fact the wood isn't going to last as long as concrete, when in direct contact with the ground. 
If you are looking for cheap and easy they are the best IMHO! 

I've done a wood pier foundation and most of a concrete pier foundation.  I would do a wood pier foundation again, but agree that there are better options (time and money wise) than a concrete pier foundation.

Well, even when the piers cost only 200 bucks, don't the joists, sheathing and flooring all add up to almost the same as concrete? Agreed that wood piers are much easier and more desirable in some cases.

[Onkeludo2]

I love slabs for passive solar and I love stained concrete due to a large-dog addiction.  That being said, I hate the inherent inflexibilty of plumbing and one slip in layout will cost you more than you saved.

Also, I believe you missed one item in your cost analysis.  Even in mild climate, a "decoupling" layer of rigid insulation is normally advised under a slab.  That insulation must have a very high load rate and tends to be expensive XPS foam.

My answer:  Pandek!  Normally used in commerical applications but the stuff can clear-span incredible distances over a basement, provides the thermal mass for passive solar and hydronic in-floor heat...and wait, there's more!  If you screw up your plumbing location you can diamond core drill through the thin slab (especially if you have said core rig from your time working for Hilti).  The ceiling of your basement is even a shiny electroplated finish which bounces light well for the underground workshop/brewery.  It is even possible, but difficult, to pour the basement stem walls and floor as a mono-pour.

Will I end up using said material for my home...building code enforcement level will decide that little question.  Most concrete-pan floors require engineering in commercial work and are almost never used (in the US) for single-family residential.

Mike