Barn foundation tall wall - vertical rebar??

[bebster]

Actually the creature I'm most concerned about is the powder-post beatle. But I plan to spray my timber frame with a borate product called Bora-Care to prevent them from going after it.

I'd like to put insulation on the outside of the foundation, but have been advised against it -- local wisdom is that it will provide a haven for bugs. That means the insulation will have to go on the inside of the foundation walls.

 

[Junkman]

I put insulation on the outside of my foundation and when I did an addition, I removed a section to see if there were any creatures living between it and the concrete. There were none. Besides, even if there were, they won't do any harm to the concrete... I like it as a buffer, but with your sand, it won't matter. If I were going to put insulation on the inside of a concrete wall, I would stud the wall with 2"x3" metal studs and use Styrofoam between the wall and the studs and then put fiberglass between the studs. Cover with sheet rock and you will have a warm wall. I was wondering why you didn't use the pre stressed concrete floor panels for the floor between the foundation walls and then build on top of that. That way, you would have a bi level building.... I like spending other peoples money!!!! /forums/images/graemlins/blush.gif

 

[yooperdave]

Have you considered insulated concrete forms? They will act as forms at first, and then will also provide wall insulation for the rest of your life. Also will help protect the hydrating concrete from freezing during winter construction.

Are you specifying smaller coarse aggregate and adding super plasticizer to the mix to aid in pumping?

Just some thoughts.

Yooper Dave

 

[MarkV]

I like the idea of pilasters, which are just small walls at a right angle to the main wall tied in with rebar. We poured a 40'x 11'6" wall and included two pilasters that kicked out 2' for added support. This would be pretty standard in my area and may have to do with the clay soil we have rather than your good draining sand. Maybe some of our engineers could comment about pilasters on long walls.

Sounds like a great barn you are going to have.

MarkV

 

[bebster]

I've thought about insulated concrete forms, but the concrete contractor wants to use his standard forms. It's hard to get a contractor it seems, so I didn't push that.

Right now planning to use a 50/50 mix of 3/8" and 3/4" aggregate. Not sure about adding super plasticizer, but thanks for bringing that up -- I'll surely inquire about it.

I've considered pilasters, but they would go on the inside, and I'd prefer not to have the obstacle there -- want to have as clean a wall as possible, since I want to be able to have a stair against it, as well as move tractor implements around on dollys in the back of the basement garage area. If it's required I could probably live with it, but right now I think the sandy soil allows me to get away with a rebar system, which is what I'm trying to finalize.

Here's a link that shows the architectural plans as well as timber frame design. The foundation plan is not accurate, and that's what I'm trying to finalize now before it warms up (if it ever does!) and we are ready to start pouring it.
barn plans

 

[Junkman]

I used concrete with chopped fiberglass in it when my garage floor was poured. The fiberglass is supposed to add strength to the concrete. I don't know if they add it to concrete used for walls, but you can check with the mix plant for their opinion... it adds about $3.00 per yard to the cost.

 

[yooperdave]

Adding fibers will only minimize plastic shrinkage cracks in the non-cured concrete - it will NOT add strength to the concrete. It will not hurt, but it really wont help in this case either.

Yooper Dave

 

[bebster]

I was also concerned about cracking, and will look into the fiberglass additive. But I was planning to put in vertical contraction joints about every 15' on the walls to control (ie direct) the cracking, especially on the inside.

 

[tomnky]

I think what you are referring to is what we call 5,000 lb. mix, it's the same mix they use for bridges and what have You.Correct me if I am mistaken, /forums/images/graemlins/grin.gif

 

[rambler]

Hum, thought vertical cracks were to be avoided, not sure one wants to plan for them?

Anyhow, the fiberglass helps the concrete bond a bit, it does not replace rebar as many wish to do - it has holding power, but not structural power? However, some folks have hated it in their floors, as the concrete etchs away over time, new fibers stick up & it is real miserable to work on the floor - itchy skin. I have no personal experience, but something I've heard about.

--->Paul