Foundation Comparisons

[r8ingbull]

First post on the site.  Nice place.  I am in the purchase phase of 14 acres in Southwest Michigan.  I've been studying the victorias cottage plans and have a few questions.  How do the various foundations perform in comparison to each other.  What are the strengths and weaknesses of each?  My building site is near a river and the water table is very high.  I have this info from a perk test:  High Water Table 48", 0"-10" topsoil, 10"-24" Loamy Sand, 24"-48" Sand, 48"-54" Loam, 54"-72" Sand.

I'm leaning towards the pier foundation due to cost and limited concrete use.  How does the floor insulation perform?  Is the reduced cost going to bite me later in high energy bills and lower resale?

And finally why don't I see more pier foundations used?

[jraabe]

Pier foundations have the same floor insulation detail as a vented concrete crawlspace. I would suggest an air barrier on the bottom of the insulated joists (Tyvek or equal). This would then perform better than standard floor insulation.

Piers can make sense in wet soils or in a flood plain, but you may need something more sophisticaed if you don't have good bearing at the bottom of the hole.

It would be a good idea to work with a local foundation contractor who knows the soils and relative costs of what will work best in your situation. That's why the plans include so many foundation options. One is not better than any other - site conditions determine that.

[peg_688]

#1: How does the floor insulation perform?


#2:  Is the reduced cost going to bite me later in high energy bills

#3:  and lower resale?

#4:     And finally why don't I see more pier foundations used?

#1 As John said with a barrier to protect it from critters , wind , etc it should be fine . You could always build a Pressure treated wood skirting with Hardi brd / wonder brd (sort of looks like concrete) to protect from those with a crawlspace hatch .


#2: I wouldn't think it would effect those , with the above measures .

#3: Now this one is more difficult to pin down , just as your having questions / issues with it maybe others would stay away / offer less on a place without a full concrete foundation , Banks can and do look at those things .

So a unfair bias MAY be possible working on this . Folks not educated / eludicated in a proper post and pier / Big Foot foundation system would think it was like a turn of the century type "rock under the corner beam " system.

 
I'd say for some of the reasons in #3, along with " less forward thinking " , "this is the way we do it ", "everyone else uses a full concrete foundation "  , type thought process.

John's plans , which I have seen , to me , are well thought out / flexible / based on sound construction methods.

I do have 30 years in the building industry as a carpenter , so those comments are based on working conditions in the field , not on office / speculation views.  

[Erin]

I'm leaning towards the pier foundation due to cost and limited concrete use.  How does the floor insulation perform?  Is the reduced cost going to bite me later in high energy bills and lower resale?

To answer #1&2--
Thirty years ago my dad built a cabin very similar to the 20x30 with the half-loft in northern Nebraska.  A bit smaller as it's more of a pioneer-cabin layout (and doesn't have indoor plumbing).  
It's on a pier foundation due to costs and site limitations for concrete.  It also doesn't have any modern heat sources/electricity/etc. which means Dad knew he had to make it snug to get the most out of the Franklin stove heat source.  
We've been up there when it was well below zero F outside and the stove kept the house nice and warm (when it was burning, that is!  Around 3AM when the fire's been out for a while, it could get awfully nippy in there...   )
Couldn't say about A/C as that's not an option (though there's been many a vacation we wished it were!)

So far as #3, I couldn't guess as he's never had any intentions of selling and probably never will.

And I'm going to take a guess that the answer to #4 is that it's probably a combination of aesthetics, habit,  possibly codes and utilitarian (a basement foundation, for example, is far more useful than a pier foundation if you can get away with one)