Home Plans And Home Designs - Underground home

I understand the most energy efficient home would be one built underground, where the temperature stays constant. I'm just interested in the whole concept.

How deep would you have to go?

What would you do with the space above the house, assuming it's in the country, on a wooded lot with a few acres?

What building materials would you use?

How would you design the entrance(s)?

What about putting skylights in most of the rooms.

What would you do for ventilation?



Thanks for humouring my questions :)

There have been thousands built since the 1970's with the last fuel crisis.

There are many books available. The main informations source was the "Underground Space Center". Googling may give some resources for you.

Generally -

1. The exposed side with many windows should face south for free heat.

2. Shading for windows in the summer.

3. Reinforced block or reinforced concrete walls.

4. Precast concrete plank for the roof.

5. Rock or lightweight aggregate backfill with drain tile.

6. Do not overinsulate the the walls exposed to the soil.

7. You can put goats and grass on the roof if you chose. - Install a handrail.

8. Very, very small furnace, if any.

9. Very good circulation and ventilation system.

Good luck!

Dick

Concrete gave you some good tips. Now here is another style of underground home. There are a great many built in the upper midwest in the 50's and 60's. They were built with block or concrete walls. However, the front of the house (the side with the door) faced south and that side is about 4 feet out of the ground, with the back side about 12" out of the ground. Roof made with rafters sloping front to back. Asphalt roof, and windows on the south side. Almost all egress windows due to fire codes.
They are starting to build some using foundation treated 2x8 lumber, with 2x8 studs, insulated and finished. These are very good homes and very energy efficient. Some of the newer homes are 6 feet under ground and 2 feet above. All are efficient.

The home Jack mentioned are usually referred to as "Earth Bermed" homes. They usually have conventional roof truss systems, but may need additiona structural support for the walls in the are wood.

Usually these homes usually relatively long back walls retaining the soil.

A wood wall cannot act as a catelever wall like concrete or concrete block, so you must have a portion of the roof structure provide horizontal support (a diaphragm) to help resist the wall loads. The concrete planks can do this, but concrete should not be supported by wood walls. A wood frame roof system will require some additional bracing and/or diagonals to provide this support for wood walls.

The convential lightweight roof system reduces the thermal benefits of the mass of the soil and concrete.

Some homes have been built this was because of the attraction to people familiar with wood frame construction.


Dick

I was not talking about earth bermed homes. Actually I had forgotten about that type. I was talking about underground houses built just the way I stated. They usually have a bearing wall down the center to help support the roof.

Lately I've been looking into earth bermed houses. I think that is the way to go.

I've been reading up on Passive Annual Heat Storage (PAHS) techniques. It's basicly insulating a portion of the earth around the house.

Working on trucks is a hobby of mine, and I've been trying to think of a way to have an attached unheated small garage for my daily driver, and below that, a heated hobby garage.

I've never seen a 2 level garage like that for a house, but the idea is to keep as much of the house under the insulating earth, rather than building out more on the surface.

What do you think, is something like that feasible?

Actually I think a 2 level garage like that would be too much work..

Instead, I was thinking of having a long single width garage, where I could have 2 vehicles bumper to bumper.

Then have a removable partition inbetween the one I want to work on, and my daily driver.