Is it generally more expensive to build earth bermed walls (basement) vs. above ground exposed construction?

Concrete walls will usually be cheaper to build, partly because you are not installing siding and there will be fewer windows. Also, you won't be building a wooden deck and floor, so your floor finish can be concrete. The other advantage is that the ambient temperaure of what lies beyond your wall will be 45-50 ish rather than 0, so your overall heat loss will be less.

If you have the option to earth-shelter, be sure to understand how it is completely used to best advantage. Insulated thermal mass evens out temperature swings. The surrounding dirt/hillside adds that mass. The dirt is next to the concrete, not next to insulation. Unless you add insulation beyond the dirt, the wall will always be cold, like a bbasement; 50-65* depending on location. Read about a PAHS house; the surrounding dirt is insulated with an umbrella cap. The dirt now stores the heat it gains in summer and returns it in winter. The recommended umbrella extends 20 feet beyond the house; that's how far heat travels in 6 months.

If you don't want to do the umbrella, put the insulation next to the concrete like a normal house, The dirt will still be 50-65, so the delta you are insulating against is much smaller.

I am in the market to build concrete earth birmed shelters. I can pour 4" walls laid flat, and stood up with fork lift. Probably costs $20 sq ft.plus labor. Roof should be lite weight compost. Water proof walls and roof and cover with liner like pond liner, heavy duty and lasts forever. Been doing concrete work since 1977. Cheaper than any other methods. Ifc's or what ever.

Afton; 4" sounds too thin for below grade?

Not really, you can use 6000 fiber mesh concrete. costs about $10 per yard extra, same used in storm shelters.

forgot to mention the walls are line in a steel form that stays with the wall

Afton; does the wall have ICC or equivelency approvals?

Posted By Afton Allen on 30 Jun 2011 05:47 PM
I am in the market to build concrete earth birmed shelters. I can pour 4" walls laid flat, and stood up with fork lift. Probably costs $20 sq ft.plus labor. Roof should be lite weight compost. Water proof walls and roof and cover with liner like pond liner, heavy duty and lasts forever. Been doing concrete work since 1977. Cheaper than any other methods. Ifc's or what ever.

$20/sq ft of floor space or wall sq ft?  If you are talking sq ft of wall, I would think that standard 8" CMU walls would much less expensive than that.

arlie6; in our area 8" CMU is about $7.50 per sq. foot of material installed

not sure what ICC is. The cmu walls are labor intensive. My House is 4000 sq ft. Cost to lay plus block $12000. cost of concrete with steel $6000 to $8000

concrete wall is maybe $2 to $3 sq ft

Posted By Afton Allen on 30 Jun 2011 07:04 PM
not sure what ICC is. The cmu walls are labor intensive. My House is 4000 sq ft. Cost to lay plus block $12000. cost of concrete with steel $6000 to $8000

International Code Council http://www.iccsafe.org/Accreditation/Pages/default.aspx is there any testing at all?

Posted By Afton Allen on 30 Jun 2011 07:06 PM
concrete wall is maybe $2 to $3 sq ft

I think the numbers are a little skewed, Concrete material alone with fiber mesh is $1.21 sq. ft. Plus pouring, plus the steel form, plus the erection equipment and labor ........................a simple slab on grade in our area is $4 - 5 sq. ft. and thats just in the dirt!, no forms, no equipment or labor to tilt up in place

Personally I would build a monolithic concrete structure using rebar and spray the concrete or hand apply it forming a vaulted roof Arch is the simplest design and has endured the thousands of years of time Roman structures are still standing. Now instead of earth spray closed cell 3 lb foam onto the exterior. 3 inches of foam plus no air leaks will give the same insulation factor of 3 feet of dirt and less upkeep. Seal the foam with silicone or stucco product Now you have an indestructible off the grid capable structure. My 2 cents www.safedomes.com Currently have 12 saferooms in Missouri and several in Florida. Make money sell domes make a commission

The concrete is tested and the structure is engineered. I say again, the walls are 5x10 or 50 sq ft. $100 per wall labor and all. I do this for a living. A safe room cost is 1&1/2 yd concrete, $100 steel, $200 door, $300 labor.$800

Posted By Afton Allen on 30 Jun 2011 08:19 PM
The concrete is tested and the structure is engineered. I say again, the walls are 5x10 or 50 sq ft. $100 per wall labor and all. I do this for a living. A safe room cost is 1&1/2 yd concrete, $100 steel, $200 door, $300 labor.$800

is the "system" tested? and engineered with a set of signed and sealed plans?

Afton; for $1,400. I'll take one

Working with an engineer now on structural beam support and safe room door. Not a problem. Still cheapest I can see. Going to drop a car on my safe room, no cheesy two by four shot at it.

Egress is always an issue with earth bermed. But I say a person should be able to live how the want.

Brad; I agree to a point , but children sleeping in an non compliant egressed room should not be put at risk by an adult. Nor should the unsuspecting second owner