Any ideas what a concrete block foundation runs?

[Erin]

DIY, not filled, but covered with fiberglass...  Anyone have a guess what it would cost to build a full basement, 28x40?

[glenn kangiser]

Erin, do you know if the surface bonded block is sufficient for use as retaining walls -- as in basement use?  I know n74tg - Tony put every third void filled with concrete and a bond beam on top along with the surface bonding.  Just asking because I haven't researched their advertising etc.

http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1178247761  Check his blog linked there also.  Maybe he can give you some info on cost.

[glenn kangiser]

Reason I am asking is that I accidently bumped a non-surface bonded wall with my crane and about 4 feet of it fell over.  It would not have worked as retaining wall for sure -but it was scheduled to be filled solid with concrete later. :-/

[n74tg]

The literature I researched before building said use one vertical rebar (1/2" diameter) every 4 linear feet of footer and fill only those cells (with rebar in them) with concrete.  I chose 3/8" rebar so halving the spacing to 2 feet was my choice.  Unfortunately, doing so pretty much doubled both the concrete and rebar used.  Done again, I'd probably follow their recommendations.

[n74tg]

Erin:
Are you talking a conventionally built (mortared) block wall or a dry stack wall?

Likewise is your "fiberglass" the same as surface bonding cement, and are you using the fiberglass for strength or for waterproofing?

[Erin]

I was looking at dry stack, surface bonded with fiberglass for strength.  
No, I don't know if this would work for a foundation application.  I've only seen it as a wall structure.  (Still researching! but looking for DIY-friendly and affordable.)

Tony, how much did you end up spending on yours?  (If i can be so nosy...)

[n74tg]

Erin:
I don't have a cost figure for my foundation walls that would help you because of the particulars of my design.

For instance, my project is 30' x 57',
And, the lot slopes down about six feet from one end to the other (so my footers will have used a LOT more concrete than a standard (level) footer because they have to step down along the way.
And, there is a 4" thick 12x22 basement slab inside of the project, with footers all around the outside
This basement room required extra digging (excavation cost).
And, there is a 4'x8' tornado shelter built in to the basement room.  It has it's own footers also and a cast in place rebar reinforced concrete slab roof.

So, as you can see, it's like trying to compare apples to oranges.  

Last total I had was about $3,000 in materials, but I expect now it's over $4,000 in materials.

Has it cost more than initially expected; absolutely (yours will too).
Was the work harder and more time consuming than expected; yes, that too.
Is there an endless list of problems to solve along the way that you didn't think about beforehand or expect; YEP.

Read the blog at bottom of post.  It will help.

[Erin]

I already have.  (well before today, even.   )  

When I was a teen, I helped my dad build a root cellar (5x10 and 9' high) with concrete blocks. All we did was mortar the joints and twenty years later, it still looks new.  But, that's a bit smaller and there's not a house sitting on it.  

But in other words, your project is bigger than mine, probably more complex and you needed to pay for excavation.  I'll probably get by at less than $4K or so....

[glenn kangiser]

Some of the strength requirements can have to do with the soil type also.  Some soils will nearly support themselves and others will try to cave in from the bottom up.

[Amanda_931]

Some of Rob Roy's books may have information on both keeping costs down and SB blocks.

His first house--hybrid cordwood/underground--had surface bonded block on the underground parts.  Covered with black waterproofing stuff (and possibly insulation).  And he's written at least twice on building without a mortgage--I'd think the later one would still be in print, doesn't show up on this list.  

http://www.amazon.com/s?ie=UTF8&search-type=ss&index=books&field-author=Rob%20Roy&page=1

[Jens]

About 9.657 in the hundred yard

[glenn kangiser]

I was waiting for someone to do that. :-/

[Jens]

count on me Glen.  I was gonna let somebody else have it but...