Terra-Dome Earth Shelter Build

[carpolisher]

Hey all,
I was that guy a few months back who posted about asking questions then disappeared. Not sure how but every time I visited the page for the next week or so it never updated so I figured the thread died. If I may still ask questions, I certainly do have a few. (Some basic background, I plan on using a two 28'x28' modules, sheltered on 1.5 sides and the roof. Not looking to build for 2-3 years, but want to do as much work as I can myself)

-I do still plan on using Terra-Dome. How has your experience been with them to date now that you've had some time to really look at their work? Would you recommend them?

-Waterproofing: What have you guys learned about it so far. I read the 10 or so pages after the web error and see there has been some problems. I've been doing my own research, but have no idea what to use. Everything sounds good, but there is just so little posted about actual experience with product/technique X. What would be your ideal drainage/waterproofing system if you did it all over again?

-HVAC: I really want Hyrdonic Floor heating (radiant floor) especially since there will be such a large concrete mass, but am having a hard time justifying the extra cost since a forced air ventilation system is almost required for safety and dehumidification. What convinced you to do in-floor heating? (By the way, I have been using http://zurn.com/images/pdf/ZPM02101.pdf as my reference for designing the hyrdonic system.)

- How are you finishing the interior? I plan on using metal studs for interior walls (low/zero smoke in the event of fire and no worries of mold damage), but are you using drywall or plastering the walls? Using products from Dietrich, I am just thinking about using plaster (also no worries of mold damage) for all the interior walls.

-What is the cost of insulating, waterproofing, and draining? They don't really mention it which scares me. I have been trying to get a cost estimate going, but if they don't include it, I worry it has to be a significant cost addition if they don't mention it.

-How good were the concrete forms? Did you lose any receptacles/box cutouts due to sloppy side wall forms allowing concrete to pour into them? This was a concern I read on another source I found. Do I need to plan on losing some so add extra?

-What solar tubes are you planning on using? I found a company that offers a really nice product, Solatube. Are these what your using, and if so, have you had any experience with them? I plan on using these in the bathroom because They can have a built in light, 110 cfm fan, and a dimmer for the natural solar light. Probably expensive as sin, but meets my bathroom requirements.

-Did Terra-Dome provide any HVAC analysis with their design? It says they provide a HVAC plan, so I'm guessing they must have sized an Air system.

-Where is the HVAC plenum located? Is it located in the concrete slab, or below the slab? (aka.. will it interfere with Hydronic in-floor heat or conduit/cable?) I got the impression it's located under the slab, but wanted to confirm that.

-What are frost footings and where might they be needed? I am guessing they would be required on the exposed walls, and normal footings on the earth sheltered walls, but haven't been able to get a clear answer from Terra-Dome on this when I asked.

Well I think that's about it for my off-hand questions. I have been having a lot of fun designing this house in AutoCAD. I have the layout done, now I'm just preparing the different plans now (electrical, plumbing, Hydronic Heating, etc.) Seeing all your projects really makes me excited to move forward soon with mine own. They all look amazing and I've learned a bit from reading all these posts!

Allow me to introduce myself. My name is Bob, I am a retired facilities engineer from New Holland. I plan on having Terra Dome construct 3.5 modules this spring in central PA. This was the result of several years studying the subject and reading others experiences shared in wonderful sites like these. My recommendation is research as much as you can on earth sheltered technology. One of my favorites is John Hait's book Passive Annual Heat Storage, Improving the Design of Earth Shelters. There is a lot of good information on the subject of waterproofing, insulation and ventilation. I look forward to sharing information and experiences with you all on this site. Thanks.......

 

[woodlandfarms]

Steve. I guess it would be too expensive to have them cut a larger window out for you? I have seen jumbo concrete saws, cool machines but they do charge a lot...

 

[patrick_g]

Regarding concerns about having concrete fill your J boxes (any conduit) or similar. You can cover the ends of conduit with duct tape or similar. Spray foam insulation is good for filling an electrical box to prevent its being filled with concrete and not very hard to clean out.

If you want your little boxes all made of ticky tacky and all just the same to be super clean then line them with wax paper or saran wrap held in place with double stick Scotch tape or equivalent prior to filling with spray foam. This makes it way easier to clean out and leave the box clean.

Pat

 

[sajurcaju]

Steve. I guess it would be too expensive to have them cut a larger window out for you? I have seen jumbo concrete saws, cool machines but they do charge a lot...

We could do that, but instead are compromising. The 2x framing around the window is coming out (the hole is square enough), and a little larger window is going in.

Thanks,
Steve

 

[SamWalton]

We found a plumber to install our black and gray water drains and venting. He is charging us $65 per hour for himself and his helper. We have a little over 200 feet of black and gray combined. Our laundry area has a shower, toilet, urinal, laundry sink, washer, commercial floor drain and two cleanouts in floor under washer dry area. The kitchen has two sinks, one on a separate island. Our main bath has a shower, Jacuzzi tub, urinal, sink and a commercial floor drain. Also our utility room has a commercial floor drain. He has a third guy that will provide and operate a small track hoe to excavate the necessary trenching inside. He said it will take two days if they don't run into rock. His estimates was $2600 for time and materials. What are your impressions on this estimate?

Thanks
Sam

 

[dave1949]

We found a plumber to install our black and gray water drains and venting. He is charging us $65 per hour for himself and his helper. We have a little over 200 feet of black and gray combined. Our laundry area has a shower, toilet, urinal, laundry sink, washer, commercial floor drain and two cleanouts in floor under washer dry area. The kitchen has two sinks, one on a separate island. Our main bath has a shower, Jacuzzi tub, urinal, sink and a commercial floor drain. Also our utility room has a commercial floor drain. He has a third guy that will provide and operate a small track hoe to excavate the necessary trenching inside. He said it will take two days if they don't run into rock. His estimates was $2600 for time and materials. What are your impressions on this estimate?

Thanks
Sam

For two days w/helper and the track hoe work included, dual drain system, I don't think it sounds bad Sam. Be interesting to hear others.
Dave.

 

[MarkV]

Cheap in my area Sam.

MarkV

 

[carpolisher]

We could do that, but instead are compromising. The 2x framing around the window is coming out (the hole is square enough), and a little larger window is going in.

Thanks,
Steve

The price is good. It may be a good idea to put in a not to exceed dollar amount in the contract. I have had projects go way over budget due to contractors exceeding their time and material estimate.

Bob

 

[sajurcaju]

Boilers

Our Terra Dome house (under construction in Maine) has three 24x24 modules, between 1700 and 1800 square feet. The concrete floor has hydronic heat. We are offered three choices for boiler:
Peerless boiler, 83% efficient
Peerless condensing boiler, 87% efficient
Buderus modulating boiler, 92% efficient
I don't know the size yet, my contractor thought it was about 100k btu.
The first two fit in budget, the third one is 2-3k beyond budget.

It seems pretty clear to me that we want the second option, a condensing boiler. I am intending to add a lot of thermal solar starting this summer, if that affects the discussion. I'd like to hear what people have to say.

Our house is fully enclosed, but the front entry is uninsulated (soon to be changed). The uninsulated part is a single wall, about 24' long, 8' tall. The rest of the house is insulated plus dirt on some walls and roof. Our contractor reports that even without heat it has never dropped below 40F. Pretty good deal, this winter has been on the cold side.

Steve

 

[dave1949]

Boilers

Our Terra Dome house (under construction in Maine) has three 24x24 modules, between 1700 and 1800 square feet. The concrete floor has hydronic heat. We are offered three choices for boiler:
Peerless boiler, 83% efficient
Peerless condensing boiler, 87% efficient
Buderus modulating boiler, 92% efficient
I don't know the size yet, my contractor thought it was about 100k btu.
The first two fit in budget, the third one is 2-3k beyond budget.

It seems pretty clear to me that we want the second option, a condensing boiler. I am intending to add a lot of thermal solar starting this summer, if that affects the discussion. I'd like to hear what people have to say.

Our house is fully enclosed, but the front entry is uninsulated (soon to be changed). The uninsulated part is a single wall, about 24' long, 8' tall. The rest of the house is insulated plus dirt on some walls and roof. Our contractor reports that even without heat it has never dropped below 40F. Pretty good deal, this winter has been on the cold side.

Steve

Hi Steve,

Sounds like progress is being made. Were you thinking of using solar hot water for the hydronic heat? I have thought about that for our house. My problem, and you may be different, is if the sun is shining, I don't need it. If we have long cloudy stretch, it would be nice by about the third day to take some heat in, but the sun isn't bright enough. I would need to heat the water in a very large super insulated tank in sunny weather and draw from it in cloudy weather.

Some solar sites like ..::REvision Asset Management Systems::.. I have visited say this isn't a good matchup due to the btu's the solar would need to provide. Plus, when I would need it the most, mid-dec thru mid feb, there is the least sun to begin with. I notice evacuated tube type collectors are getting pricey. The link is to revisionenergy.com. It works but won't give up on the wrong name.

Good luck in your research.
Dave.