30x40 Earth Berm Passive Solar in Maine

[Bishopknight]

This weekend I started building the footers for my 30' x 40' earth berm, passive solar, insulated slab house. I'm mainly doing this myself, pay as I go, paycheck to paycheck. Let it be known, the only experience I have building prior is with the 12x16 house shown below and described at this link.

http://countryplans.com/smf/index.php?topic=4569.0

I bought 10 acres and a John Deere backhoe this spring. I wasn't able to start this project sooner because this summer has been so rainy and its taken until now to prepare the housepad.  It was forest originally when I bought it. I built the driveway this summer. This pic was taken north facing. I brought in 3 loads of sand to build up the pad so far.





I have a healthy respect for people who build foundations



Form boards came next. I used 2x10's. I'm not worried about frost heave because again, it will be earth bermed.



Leveling stakes and strings came next.





Next is the plate compactor rental, sweat equity and another load of sand. Then the plumbing comes after that.

[glenn kangiser]

Looks like you were busy with the backhoe.  Can you tell us how you are going to prevent the infiltration of water - French drains?  Umbrella?

[Bishopknight]

Aren't backhoes great Glenn?

My drainage concerns were #1. I created a 30" ditch (future french drain ) around the perimeter which drains downhill. That will prevent the majority. Rock gravel with perforated drain pipe will round the perimeter and also be drained away as well. That should prevent the minority. The rest I leave in Gods hands

[glenn kangiser]

I've been doing backhoe work for a week now - much on a 40% slope-- it's fun.

Thanks for showing us what you are doing on this.

[Redoverfarm]

Bishop I would say you will be OK building. Hey the original that you built is still standing.

[Lorangerlife]

Bishop,

I have to agree man... You did a bang up job with the 12x16.  Watching your build showed me that 12x16 could be a livable space while I build my house.

No doubts coming from my side of the fence that you will do as great a job on your house as you did on your cabin.

Andrew

[ScottA]

What a great spot. I can't wait to see this one come together. 

[mvk]

Congratulations, great start, thanks for the pictures.

Is the south side walk out? I was wondering about frost on that side.

What a great project, can't wait to see it. Your cabin came out great too.

MVK

[soomb]

Will the subterranean portion be poured concrete, block or other?

A bold project. What was your learning process? read read read then do or some reading and see how it goes?

[glenn kangiser]

I like read - do - read - do read- do.

After a while you can skip the read part and just do - do 

[soomb]

or run them together and re-do re-do. 

[Bishopknight]

Thats pretty much the process soomb!  I try to keep things one-day-at-a-time when I build something I've never done before.

The walls haven't been decided yet, either ICF or surface-bonded concrete with exterior blueboard insulation.

These are my main reference materials incase anyone is interested.

Earth Sheltered Houses by Rob Roy
http://books.google.com/books?id=0gCQl64B1iAC&pg=PA20&lpg=PA20&dq=richard+guay+house+earth&source=web&ots=GcarPxWUG4&sig=5Flov1fmN3tdeCg72qoefrP0iKo&hl=en&sa=X&oi=book_result&resnum=1&ct=result#PPP1,M1

$50 and up Underground home by Mike Oehler
http://www.amazon.com/Fifty-Dollar-Underground-House-Book/dp/0442273118/ref=pd_bxgy_b_img_b

Working with concrete
http://www.amazon.com/Working-Concrete-Rick-Arnold/dp/1561586145/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1224076563&sr=1-1

and this excellent website
http://www.ourcoolhouse.com/

[glenn kangiser]

Good refs.

[soomb]

ahh ourcoolhouse.com  love that site.  that is one smart guy.

[MaineRhino]

Looks great Sean!

[Bishopknight]

This past weekend I had to redo the forms because the sand wasn't high enough, the south east corner did not have a wide enough drainage skirt and I didn't like the forms zig zagging in and out ( would have been hard to lay in the XPS foam board). I also had a dump truck fall into my driveway ditch saturday morning while delivering another load of sand. He tried blaming the road material and not the fact he was 4' from center.

I completed the house plan yesterday and drew the supply and DWV diagram today. I'm meeting with the plumbing inspector to go over them this weekend. The first draft house plan is below.

Lastly, I had a really hard time finding Dow Blueboard High Load 40(psi) for the slab footers. I located some from a supplier in Portland, Maine. They are 2'x8' - 2" thick for $14 each.  I really lucked out finding them, 2 other places wouldn't sell them unless I bought 98 at a time.  They only had 16 left and I only needed 16.5 so I'm going to just cut some 2" , 25 psi dow blueboard (from home depot) into 1' x 2' sizes and space them in between the 8' pieces on the 30' side.

Btw, I found out there is a big difference between EPS and XPS Styrofoam. One is expanded which can get wet (EPS) and the other is extruded which stays dry (XPS). Rob Roy recommends XPS for all under slab insulation because once it becomes wet, it loses much of its insulated value.

[Bishopknight]

Monday update:

I bought 2 more loads of sand to build up the front of the pad foundation and also get the inner pad about the right height. Then picked up the XPS insulation for the slab foundation and built the formboard for the front, leveled and spiked it.



Next I used a 26" board to go around the perimeter and roughly level the footer base by hand and rake. Then rented a plate compactor and went to work. Btw, a 180 lb wacker is not easy to lift on/off a trailer , up a pad and over a footer wall by yourself!



Yesterday, In my 3d design software, I used the dimensions ruler to tell me how far apart each plumbing device was. I ran measured string lines and then started digging and laying pipe. I made absolute sure the pipe dropped 1/4" per foot. Laying the DWV (drain, waste, vent) was pretty fun. Especially when its compacted sand, not hardpan clay! Also the familiarity with having done the plumbing myself in the little cabin made it easier. 





























Here is the vent pipe for the woodstove




The plumbing for the bathroom was tricky, after the foundation is poured, I'll remove this wooden form box to give me more space approximating the p-trap for the shower. that slanted pipe is the cleanout and the other 3" beside it is for a future bathroom if I decide to build a second floor.



This is how it looks now.

[glenn kangiser]

Hey BK thanks for the update.  Looks like you have been busy.  You know about wrappiing the pipes where they come through the slab w/cardboard or other wrap to keep the concrete from gripping and possibly breaking them?

[Bishopknight]

No, I didn't know that, thanks Glenn! I'll make sure I wrap the exposed PVC.

Also, I've been emailing the author of "Earth-Sheltered Houses", Rob Roy and hes been very helpful answering my questions. Most recently regarding whether a vapor barrier was needed in addition to the XPS foam insulation. He said not in his view, that without the extruded, you would need the vapor barrier to slow the rapid set of the concrete. That basically the extruded does the same thing.

[Mike 870]

Awesome project, I can't wait to see how it progresses.  I found this site when I was trying to figure out how to do a foundation and septic.  It might help, it's might not.  It's not for your region, but it might be good for some pointers.  http://www.eco-nomic.com/septic.htm