Piers Vs....

[scody311]

Hey folks,
I gather from reading some of these comments that Piers are frowned upon. I do have the 1.5 story plans (awesome, thank you)... and it definitely gives me an option for Piers.
As a DIY home builder, piers are intriguing. I can pretty much do them myself, the cost is right... and it seems I'd be alright...

But lots of folks (including one of my friends who is a GC) warn me AWAY from them.
I'd like to hear thoughts pro/con for using Piers.

We are on a grade of 20 feet over, 5 feet down. I imagine a crawlspace with trenches dug, and the wall built, and the concrete poured is going to be a LOT more expensive, but of course... I want to do this right.
Can I get a discussion on the matter?

[flyingvan]

I've never built on flat ground.  That slope is moving---not fast, but it IS flowing downhill.  A one piece, solid foundation is a good investment, provides storage space---and sets a good theme for the build, of taking the time to do it right

[ChugiakTinkerer]

scody311, you've precisely hit on why piers are so appealing to the DIY builder.  They are doable by folks with limited skills and equipment, they can be put in the ground with not much more than sweat equity, and in a lot of cases they are more than sufficient for the job.  Where other folks take issue with endorsing them as a viable method is because they fail a lot more frequently than do code-approved foundations.

With a prescriptive foundation, you know that as long as the construction is according to code the foundation will last many decades, if not centuries.  With piers there are too many variables to come up with a straightforward recipe.  So if you want piers and are building in an area with code requirements then you will need an engineer's stamp.  That stamp indicates that if the pier foundation is built to spec then it will withstand the forces and motions of the earth and wind.

Should you have an engineer-approved pier design I bet everyone here would be offering encouragement and perhaps even technical support in building that design.  But without that engineer's stamp, how do you know that the foundation design is adequate?  That's the concern I've seen expressed by folks that frown upon pier foundations.  There are too many ways for a DIY builder to get it wrong, and there are examples on this forum of actual failure.