Looking to do a crawl space type wall about 36" high like 8" thick.

Want to also do the footings with IFC.

Is it possible to lay 2" insulation under the footings to avoid a thermal break

I see several manufactures any that are ez to use, see a lot a Fox product out there.

What is the ball park cost per sq ft of the forms w/o rebar?

Do I even need vertical rebar at that height?

Building Ga if that helps manufact & avail

Posted By gosolar on 23 Mar 2015 02:42 PM

Is it possible to lay 2" insulation under the footings to avoid a thermal break

I see several manufactures any that are ez to use, see a lot a Fox product out there.

What is the ball park cost per sq ft of the forms w/o rebar?

Do I even need vertical rebar at that height?

Building Ga if that helps manufact & avail

Yes, it is possible to lay 2" of EPS under the footings BUT is it cost effective and worth the hassle of dealing with engineers and county inspectors who will have a fit when they see that?

Having rigid EPS under a footing is something not for the faint of heart. It must be 100% engineered and then dealing with the cost and the inspector who will red mark and flag that condition/detail. People have been placing footings on raw earth for a long, long time but putting foam under a footing is a new thing here for the US.

Unless you are in Zone 6+, I don't see the benefit in insulating the footing. Even in Zone 4 climates where footing depth is usually 18-24", the ground temp in that area is around 55F - 60F even in winter. A Zone 2-3 ground temp footing would be in the 65F range.

Being that you are in Georgia which sees Zone 2 - 3 or 4 depending on where exactly you are at. It would NOT be a beneficial move to install foam under a footing.


Typical ICF costs (forms, rebar, concrete, labor) is around $10 - $15 per wall square foot, depending on area, experience and difficulty.

Foamglass might be easier to get approved for under a footer than EPS since it has good compressive strength (90 PSI).

Also Dow now has a structural foam for this purpose...if you can find a stocking distributor

You are only going 3' height in an ICF crawl basement, I see some huge cons of foam under the footing but not any benefits, especially in your climate area.

Form cost $3 to $4 per sq ft. I agree with Lbear nothing to be gained

got a much better suggestion....capillary barrier for the footer......google it

got a much better suggestion....capillary barrier for the footer......google it

the capillary barrier  looks like a great idea, I guess I'll forget the 2" foam Idea.

What about this Monpour system?  link

also going just a height of 3' are adjustable supports needed or can 2x4's every 8' work ok?

Posted By gosolar on 24 Mar 2015 05:54 PM
the capillary barrier  looks like a great idea, I guess I'll forget the 2" foam Idea.

What about this Monpour system?  link

also going just a height of 3' are adjustable supports needed or can 2x4's every 8' work ok?

The monopour looks nice but that is another red flag on the inspections. The county/city inspector usually wants to see the footing hole, then they want to see the footing AFTER the pour BUT BEFORE the stem wall goes up. You will get resistance to the monopour by some county inspectors. Not to say it can't happen but get ready for some push and pull.

A one pour footing and stem wall is "stronger" but once again footings and stem walls have had cold joints for a long, long time and house have not fallen because of a cold joint. That is what footing to stem wall rebar is for.

Eventually you will have a cold joint somewhere.

In 29 years of building I have never had an inspector (1) come and look at a footing after the pour but before the wall was built, and (2) when doing a mono pour had any resistance...and I have built in the toughest, most stringent places in North America...including The State of California...which has the most enforced code out there

So please do not scare people off with this misinformation. Unless you have personally had this experience, it's gibberish and hearsay. If the EOR draws it and approves it that way and it does not contravene any building code, your inspector will have no issue with it.

Posted By Chris Johnson on 24 Mar 2015 10:44 PM
In 29 years of building I have never had an inspector (1) come and look at a footing after the pour but before the wall was built, and (2) when doing a mono pour had any resistance...and I have built in the toughest, most stringent places in North America...including The State of California...which has the most enforced code out there

So please do not scare people off with this misinformation. Unless you have personally had this experience, it's gibberish and hearsay. If the EOR draws it and approves it that way and it does not contravene any building code, your inspector will have no issue with it.

It's not gibberish in my area. Read it and weep...

Footing Inspections: After the trench is dug and reinforcement is installed, and prior to placement of the footing material.

As per the government website in my area:

Required Inspections

All construction or work for which a permit is required is subject to city inspections and must remain accessible and exposed for inspection purposes until approved.The following inspections are required, depending upon the amount of work being done:

1. Foundation inspection: When the excavation for footings is completed, with steel reinforcement in place, but before any concrete is placed.
2. Footing inspection: See Below
   
3. Under-slab or under-floor inspection: When under-slab or under-floor plumbing, mechanical and /or electrical is installed, including the subfloor.
4. Masonry inspection: When required; reinforcing steel is in place, but before grouting.
5. .......

FOOTINGS:

• Footing layout/dimensions must match approved plans.
• Footings dug to width and depth as shown on approved plans.
• Footings 12 inches (18” for 4500 elev+) into native soil with bottoms squared/level.
• Check soils: no loose material, mud, organic material in footings, no expansive soil.   If fill on site, a copy of the soil compaction report must be available for inspector.
• Expanded footings installed per the approved plans with additional steel as required.
• Exterior piers and/or interior footings installed per the approved plans with steel.
• Steel properly lapped, supported and size indicated on approved plans and grade pins set.
• Bulkheads installed in stepped footings.
• Vertical steel (J bars) on site for placement at time of pour unless retaining walls then J bars must be tied in place to horizontal steel per the approved plans.
• Plumbing/electrical sleeves cannot pass through the footings (they must be placed under footing or through foundation wall).
• Plumbing sleeves must be twice the diameter of the piping that will pass through it.
• Ground electrode (if required) installed ( #4 bare or stranded copper, 30 feet in length with 20 foot in footing around steel and 10 foot out of footing).

STEMWALL:

Posted By Chris Johnson on 24 Mar 2015 10:44 PM
In 29 years of building I have never had an inspector (1) come and look at a footing after the pour but before the wall was built, and (2) when doing a mono pour had any resistance...and I have built in the toughest, most stringent places in North America...including The State of California...which has the most enforced code out there

So please do not scare people off with this misinformation. Unless you have personally had this experience, it's gibberish and hearsay. If the EOR draws it and approves it that way and it does not contravene any building code, your inspector will have no issue with it.

The other factor is in the FAB FORM fabric. Do you use that system?

My question is how will the inspector SEE that the footing trench is flat, level and smooth on raw native undisturbed soil if the fabric is sitting in the trench covering the ground and sides?

Chris, just checked the code where I'm building

they require a second inspection after pouring before framing.

I do mono pours with my own system and we have this discussion from time to time so I have a engineer that stamps my customers' plans and it's the end of any questions.

Ok the mono pour system on a job this small for a stem wall is not cost effective IMO.

About $6.00 a linear ',

I only need to 12" below grade here with a 8" footing, it's a 24x36 box, so I'll just use wood and reuse what I can on interior.

I'll still use FRC for the stem walls

No where in your post from the government website does it call for an inspection AFTER the footings are poured and prior to building a stem wall, which is what you stated earlier

Let me give you a brief synopsis

Excavate
Survey Corners (Optional, but recommended)
Form Footings
Place Steel

Inspection

Place Concrete in Footings
Build Stem Wall with Steel

Inspection

Place Concrete in Stem Wall
Waterproof, Weeping Tile, Gravel, etc, etc as needed
Survey (Elevation and SetBacks, this varies by municipality as to when it is required, now is the easiest time to check and confirm, and if it was done prior to building footings it should be dead on correct)

Inspection

I use my own system similar to FabForm

The inspector can use common sense and know if the ground is flat, level and square, when quality of soil has been a concern, probing the ground on an angle under the mono pour system is sufficient to make sure there is no soft spots, and if soil is a concern, a soils engineer should be employed on the project as your inspector does not want any responsibility if soil conditions are questionable.

gosolar - re-check that info I think you have a misinterpretation. Use PT wood for your footings, they can be re-used as your sill plate normally, confirm that with local codes if PT can be used

I agree with Chris, except I only pour on a crushed stone base. No native soil for me. If you ever watch an excavation being done, there is no such thing as undisturbed soil, unless they use a tamper

I agree with Chris, except I only pour on a crushed stone base. No native soil for me. If you ever watch an excavation being done, there is no such thing as undisturbed soil, unless they use a tamper

We do mono pours with foundation insulated. As long as an PE approved the plans it is typically a couple minute chat with the officials. Though do talk to them first. We also video all ready to pour assemblies so if there is a question you can show them what you did. Also keep a journal and date and time and name of were the information came from when you get information from an official.