Terra-Dome Earth Shelter Build

[sajurcaju]

Steve,

I am just getting started.. Terra Dome is supposed to show up any time to start our build in PA. For the water proofing/control... after the concrete and penetrations are sealed.. we plan to add some fill and then cover the entire roof with 6 mil poly, extending it several feet past the walls and sloped to a perimeter type drain with river rocks. The poly is cheap and easy to install. The idea is to keep the soil around the house dry. I never had much faith in the black tar stuff lasting long. Actually we will sandwich insulation board between several layers of plastic creating an insulation water shed umbrella.

Just my 2 cents.

Bob

6 mil isn't very thick, I think you may get some holes in it. Instead, you could use a pond liner, something that will take some scraping without penetration. Sounds like a good idea, wish we'd done something like that.

I don't think TD puts enough downspouts in. I'd consider adding more. Our roof doesn't have any slope to it, but we only have one downspout for the whole 100' long structure (as installed). We've added two since, but it is much easier to do up front.

Keep an eye on their work in flat areas. We ended up with 3" deep puddles with nowhere for the water to go (thus the extra drains).

Steve

 

[patrick_g]

Guys, I used a product called Insuldrain. It is 4x8 foot sheets of foam insulation with tongue and groove edges. One side of the sheet has channels in it both vertical and horizontal. That side is covered with Tyvec filter material. I installed it against the outside of the below grade concrete walls of my walk-out basement. The filter cloth side goes to the outside (backfill side.)

You don't have to glue it to the concrete but a little dab will hold it in place until you backfill.

How does it work? Well, besides giving a good R-value it is an excellent system for avoiding water leaks through any cracks in the concrete. Pretty much all concrete cracks and if you have appropriate steel in it (rebar, mesh, etc) the cracks are just cosmetic and not of structural concern. If there is a head of pressure from standing water (about one PSI per two feet of head (water depth) even microscopic cracks will leak. Any water in the backfill next to the Tyvec filter cloth gets filtered by the Tyvec and then goes into the channels in the Insuldrain and falls to the bottom where you will have a French drain.

The ground water at the site of my basement is about 5 ft above the level of the basement floor slab. I have volunteer cat tails growing behind my basement (walk-out side) and they thrived during a recent record setting drought. My walls were formed with Snap-Ties so there are plenty of little channels for water to leak through the wall. During the wettest year on record our basement walls did not leak a drop.

If you tape a piece of vapor barrier to the wall or floor and leave it a while (I can leave it for a week or more) when you remove the plastic you may notice that the concrete is darkened where it was covered. This is water. In bad cases there may be condensation/liquid water on the inside surface of the plastic. The uncovered part of the wall looks dry because the water coming through the wall is evaporating. Your arm may look dry but wrap it in Saran wrap and in a little while you will see liquid. Same deal with the concrete walls and floors.

I get NO discoloration of my walls or floor. They are quite dry even though there is water on the other side of the walls up to 5 ft above the floor! My walls are not covered with a membrane, not painted with any sealer, nor was any additive put in the mix for waterproofing. The Insuldrain product ensures that there is no head of pressure to force water through the cracks in the walls or the holes where the Snap-Ties penetrate the wall.

The water diverted by the Insuldrain falls into my perimeter French drains and drains to daylight near one of my backyard ponds. Those drain lines have run a constant stream of clear water since the drain lines were installed.

I know I may sound like an infomercial but I'm just reporting what I did and how well it works. I am not connected to the MFG or distributor in any way except as a customer.

I did employ a PE who was a consulting soils engineer so not all the drain ideas were mine alone.

Pat

 

[SamWalton]

We installed our septic tank today and once again were required to jack hammer the black water connection between the house and the septic tank.

 

[sajurcaju]

Sam, you must be getting pretty good with the jackhammer by now. Lotsa work.

Update on roof drainage/leak issues from Maine:
Our house is 3 modules, plus one for the garage and two big ones for shop and barn. I'm still amazed that for all that roof area, covering 100 feet end to end, Terra Dome only gave us one downspout. We've added two more.

The front of the shop has always dripped through the form ties. We (well, the crew we hired) dug up the entire parapet wall (i.e. down to the roof itself) and found 6" of standing water in the trench. There is a drain near, dug that up and found that the "perimeter drain" tube was only 3' long. This is on the front of the house; the single TD supplied drain is on the back. I dug up a small spot along the back, and found damp sand, but no standing water. The conclusion is that our front perimeter drain (at least on the shop) doesn't work. I don't know if the house has a tiny slope back to front or what. We added a perimeter drain the full width of both the shop and barn, plumbed to the drain we added at the front of the shop. We also put some hydraulic cement in to seal the ties. Why this wasn't done the first time, I'm sure I don't know (that contractor is no longer on the job).

What we had before in the added drain was a hole down through the overhang, connecting to a path out for the water. Above the roof, the hole met a T and connected to drain tubing. This pretty much guarantees an inch or so of standing water, that doesn't reach the bottom of the tubes (held up by the T). We eliminated the T and put a rock screen over the hole. Above that we made a rock pit--the perimeter drain pipes just dump into the rocks, which drain down the hole. Any surface runoff will also drain into the rocks.

Since we have had a problem with the water staying *above* the insulation, with the drains below, we also added perimeter drains above the insulation, just sub-surface. I really don't want to have to go in there again. Accuse me of belt and suspenders.

The perimeter drains we dug up and placed are now covered with 3/4" rock, then landscape cloth. Note that rock is not called for in TD plans.

It will take a good hard rain to tell how well this really works. I think a pond liner over the roof and up the walls is a very good idea for anyone building one of these (but somehow you still have to deal with roof penetrations and attaching to the drain pipes). Add more drain pipes.

On a related note, I found some reasonable caps for the plastic culverts we used for roof penetrations. They are called "split end caps". You have to buy the same brand cap as the tubing you use, they don't match up to other brands. These were about $33 each. You can see the one we bought here:
http://www.ads-pipe.com/pdf/en/ADS_Product_Catalog_06-07.pdf
Look on page 15. They are sized by inside diameter of pipe.

Steve

 

[SamWalton]

Our home doesn't have any down spouts. We plan to use gravity and drainage pipe located in the lowest areas between modules and along the parapet walls to channel the water to either the east or west berm wall and down into the French drain system along footing walls. We only have a few leaks at the cold joints. At one time we didn't have any leaks with the Econline-T, which was only applied to the cold joints and low spots. Then we applied the Econline-R product over the whole roof and the previously applied Econline-T. The Econline-R re-emulsified and or de-bonded from low areas where water collected. We were never able to reach a solution through Tom Dick of Eproserv of Kansas.
We are officially done with the septic system. We are focused on the massive network of conduit systems under our floors. A few pics of our progress.
Good luck on the leak repairs.
Sam

 

[SamWalton]

We installed our electrical conduit from the transfer switch to the primary and secondary load centers.

 

[sajurcaju]

Our home doesn't have any down spouts. We plan to use gravity and drainage pipe located in the lowest areas between modules and along the parapet walls to channel the water to either the east or west berm wall and down into the French drain system along footing walls. We only have a few leaks at the cold joints. At one time we didn't have any leaks with the Econline-T, which was only applied to the cold joints and low spots. Then we applied the Econline-R product over the whole roof and the previously applied Econline-T. The Econline-R re-emulsified and or de-bonded from low areas where water collected. We were never able to reach a solution through Tom Dick of Eproserv of Kansas.
We are officially done with the septic system. We are focused on the massive network of conduit systems under our floors. A few pics of our progress.
Good luck on the leak repairs.
Sam

That sounds pretty unfortunate with the Econoline stuff. Hope you can get it straightened out. I'd escalate if Tom has dropped it.

What are you doing for heat? I didn't want to put forced air under the slab because it would have to be high pressure (i.e. not huge ducting) and probably pretty noisy. We did put in ventilator units (in/out with a heat exchanger between); it would have worked a bit better if we'd run those under the floor, but didn't. Yet more complexity to the massive conduit system.

Steve

 

[SamWalton]

That sounds pretty unfortunate with the Econoline stuff. Hope you can get it straightened out. I'd escalate if Tom has dropped it.

What are you doing for heat? I didn't want to put forced air under the slab because it would have to be high pressure (i.e. not huge ducting) and probably pretty noisy. We did put in ventilator units (in/out with a heat exchanger between); it would have worked a bit better if we'd run those under the floor, but didn't. Yet more complexity to the massive conduit system.

Steve

We have multiple methods of heating. Our Green Wood Boiler will be on a closed loop with solar panels, which heats the 120 gallon indirect hot water via heat exchanger, radiant floor heating and hot water coil in HVAC system, a heat pump forced air system using General plastics under slab loop and plenum system, passive solar and Earth sheltering.

 

[sajurcaju]

We have multiple methods of heating. Our Green Wood Boiler will be on a closed loop with solar panels, which heats the 120 gallon indirect hot water via heat exchanger, radiant floor heating and hot water coil in HVAC system, a heat pump forced air system using General plastics under slab loop and plenum system, passive solar and Earth sheltering.

Sounds excellent Sam. I hope to add some thermal solar panels to preheat hot water and heat, but something tells me it won't be this year. Too many irons in the fire.

Steve

 

[SamWalton]

We are finally ready to pour the footing where our black and gray water leave our home but also two French drains, a fresh air supply for the second wood stove and electric conduit for future use.