Would this work ?

[eddienpk]

I have an idea for footings for a pier foundation for my log home. Dig a square hole 24 inches deep
24 X 24 square and place 2 cinder blocks in bottom of hole side by side with 3 pieces of rebar cut 24 inches long on top of the hollow blocks. Place another layer of blocks on top of these and rebar on top again. Pour this hole full with cement.
I am at a loss for piers themselves, but I have aquired a boat load of cinder blocks and would love to be able to strengthen them enough to use as piers if possible. Suggestions please on above ground piers.

[WillandHelen]

I'm not quite sure how you are going to orient the blocks, but just know that a solid pour is much stronger that pouring in and around blocks or pouring a form over several days instead of one continuous pour. Don't be afraid to pour something big by mixing a few batches in a wheelbarrow or front end loader over the course of a few hours. I have done this several times for steps and footings with great results...but it will wear you out!

[StressMan79]

Where you dig a trench ~2'deep, then put in some 2" Blue under slab insulation to the bottom of the trench and 6" above it. support this to the outside of the foundation. aslo dig out roughly 3" on the inside of the trench. Put in an inch or so of sand and tamp down, then insulate the slab with 2-4 inches of the same foam that you used around the perimeter. Put 6" of gravel in the bottom of the trench, wrapped in landscape fabric. use 2 #4 bar around the center of the perimeter of the trench ~2 inches from the bottom (separated of course). Then bend rebar on 2' centers in bar to slightly above grade into the slab. finish the rebar for the top of the slab. It will help to tie all this rebar together with wire. Pour your foundation. It is now insulated and reinforced.

I would not do this on my first house. I would use a traditional footer and stem wall/icf. However, I am building a small mother in law house. I'll let everyone know how it goes and holds up. I may use this for my next place if it works good. Otherwise I'll use a more traditional method and eat the cost.

-Peter

[dvb]

Peter,
I am sure the reason to make sure your foundation is below frost line is to make sure you don't have frost heaves under the foundation. Frost heaves are caused when wet ground freezes and the ice expands causing the soil to expand upward. Insulating the foundation will not stop this from happening. Maybe I missed something in your post?
Dean
On another note; did LHBA folks ever come up with a solution on the double signature posts?
LHBA Class of Feb. 2006
Best investment of my life.
http://s522.photobucket.com/albums/w343/deanbrossman/

[StressMan79]

that is what the insulation around the perimiter is for. It protects the dirt under the footer (which is above the frost line) from freezing. My frost line is 30 in deep, this allows me to only dig 24' down and do a slab on grade, the cheapest form of foundation (no beams, etc). Like I said, I don't think this has been done with a log home (one of ours) but It was recommended to me by the building inspector out there, and he sent me literature on it.

Like I said, I plan to just build a Guest house first, with enough solar gain to protect the dirt under the foundation from freezing when I'm not there. I also plan to beef up the design somewhat (go to a 2'wide at the base rather than 1' wide, use 1/2 inch rebar for everything, some is recommended @ 3/8).

Look us FPSF on google for more info.

[Curt Hicks]

I know, I know i need to take the class!!! But iam looking at buying a 1950 house w/ 3.5 acres...it is a raised concreat foundation for a stick frame house (dont want the house)...question is how wide does the foundation need to be for the logs..and if too narrow can i widen the foundation??? or sould i just walk away?? thanx^0^

[Loghomeguy]

None of us can answer that without a detailed description of the existing foundation. That would include: width of footing, size of stem wall, depth of footing as related to frostline, amount of rebar, type and stability of soil, etc.

Normally one log weighs as much as a stick frame wall so normal foundations are not designed for such, but there may be exceptions.

Best wishes,

Mikey

[Yuhjn]

A log home built the LHBA way is incredibly heavy. Unless you have extensive knowledge about foundations or have a good engineer helping you, deviating from either the pier block or stem wall foundations recommended by the LHBA is a bad idea.

The single worst problem you can have with a log home is a foundation problem.

One thing you can do with your stockpile of blocks is use them to fill in the sides of your pier foundation, once you've built your home (this would be non-load bearing). This is assuming you want to close those holes which most people dont.

Are you signed up for the class? I think it might change your approach if you take it.

[Timberwolf]

I was actually suprized that it was fairly conventional.

He had never done a LHBA house, but he has done a bunch of Scandies, so the weights are similar.

Calculated the weight of the wall logs at approx 50000 lbs

Footing: 8" thick, 24" wide, 3 continuous strands of rebar spaced 6" apart.

Foundation wall: ICF with 8" core 9' high. Vertical rebar every 4 feet from footing to top. Continous horizontal rebar every 2'.

This is actually pretty standard, with the exception of the 8" core. For a stick frame house I could get away with 6" concrete core in the ICF. Although the ICF is potentially stronger than a straight poured foundation, I believe they don't give consideration to this, so a 8" thick poured wall is the same.

Of note, earthquakes are not an issue here, only snow loads.

Given the specific requirements for a LHBA home, I think you'd be hard pressed to determine if an existing foundation could even be considered without taking the course. Even then, I'd want a qualified engineer to inspect the foundation to be sure.

Jason.

[Curt Hicks]

i would have had more detail if i was in the country (u.s) to do a walk through..but i was not even thinking of the weight facter..MAN i need to take the class^0^ thanx agin^0^