900 Sq. ft Earth Bermed Passive Solar Home in Upstate NY

[Bishopknight]

Wow, looks awesome Jeff and Deb!

Ya, i think if you had a wood stove going, you'd have no problems.

[rickeyleee]

Very fasinating project.  I spent the entire morning yesterday reading this one thread and will keep following it to completion.  My hat goes off to the 3 of you.  Too bad Tuck isn't a little older to help lift those blocks. I have 7 acres of rough ravine and scrub oak with about an acre of flat ground with a lawn that looks better than my lawn in town and plan to build in the next few years.  I have been looking at earth tubes also but am still confused on how you convert the approx. 55 degree air from the ground into 70 degree heat for the winter. 

1. I have read some about the air to air heat exchangers but their sure isn't much out there as far as costs.  Not a lot about HRV sytems either. The post I did read explained that most local heating and cooling places don't know anything about them.
2. Heat pumps aren't recommended for central Iowa because of our winters but my idea was to possibly installing the unit in a atatched garage with the heat tube outlets being vented in that area for the heat pump to work with that air rather than below zero weather outside.  The same of course would be true for helping with the very humid hot conditions we have in the summer.  I read somewhere that you need a minimum of 10' on all sides of the heat pump outdoors but if an insulated garage could help with both the heating and cooling with the earth tubes, it seems like this would be a pretty effecient way to go.  Does this make sense?..... any ideas.  I plan on eventually dabbling with some hydro power from the creek in front of the house, a few small wind turbines and some solar panels to provide 50 to 75% of the electricity.   
3. I want to incorporate a berm on the north side of the house and like the dry brick approach to a foundation and back wall and a lot of glass on the south side with concrete slab floors for some thermo mass but concerned about the interior design for the passive solar heat to optiminally flow through the two story home.  Like the idea of pouring a slab over cinder blocks that are layed so that the holes are aligned to flow into register vents but would the cost and benefit be worth the time and money?
4. Also like the idea of a wood stove in the middle of the house with a block and brick surround with plenty of spaces for the brick to vent the heat from it's thermo mass but can't find anything about making such a surround for a typical steel fireplace. I suppose you could just allow some room around the sides, back and top for an air barrier and convection would take care of the rest and allow the thermo mass of the bricks to provide heat long after the fire goes out. (another dry stack project maybe)
5. I like the idea of a forced air back up system of some kind and once again the heat pump seems to be the most efficient (don't want to mess with a big propane tank in the yard). My big concern is how to begin to plan any duct work when the house will be on a slab.

Any ideas would be greatly appreciated. 

[EcoHeliGuy]

I don't have a lot of time to dive into your questions, but I will tackle the first one.

In your house the temp would be 70 degrees, out side would be below 32, and as you said the tubes would heat up this air to some number around 55.

IF you did not have this earth tube, your house would draw air in through cracks, seals, and all other imperfections in your walls, doors and windows from the out side (which is below 32). this air is drawn in by fireplaces, exhaust vents, and exhaust fans in your house.

Its a whole lot better to heat the incoming air from 55 degrees instead of 32.

hope this helps 

[speedfunk]

Hi Rickey Lee and welcome.  I hope when you do decide to build you share it with us.

Eco hits it on the the head.  The best air temp you can possibly get entering the house through the tubes in the temp of the earth surrounding your home.  In my design I hope to raise the ground temp surrounding my house.  This will allow me to raise the temp the air enters at above the standard 40 degrees the our ground is in upstate NY.  Even with a different design ... 40 is a lot better then 0.

1.  I briefly looked into a HRV (heat recovery Ventilation system).  I like you found very little to go on.  I decided on the earthtubes as it's more passive of a system.  Not so dependent on electric.  This was my choice though, there is certainly  some benefit to plugging it in and it's ready to go.  It just didn't fit what I wanted to do.

2.  A bit confused on this one.  Are you talking about an in ground heat pump?  Pumping heat from the cold outside wouldn't do much for you.  I'm not big on heat pumps personally, although others seem to like them.  From my reading , the electric is cut down to a 1/3 of standard electric heat.  So while that is certainly an improvement the cost and the complexity of the system did not fit with the Passive Living home that we are trying to create.  Our design I feel is a much more simple,cheaper and less maintenance compared to a heat pump.  

3.  I think you bring up a good point about multi-floor passive solar houses.  Ideally you want to allow a convection cycle.  I guess this could be accomplished in a variety of ways depending on your floor plan.  Keep it open as possible.  Maybe to the rear of the house use pvc tubes that connect the highest part of the house and the lowes ( this is just my idea of something that might work though).  The concrete block idea I have some concerns with.  Warm air tends to drop moisture when hit with surfaces of a cool nature.  When it does how will you be able to clean down below your concrete floor.  The real advantage to the pvc (or any other dense plastic with no corrigations) is that is easily cleanable with a rope and a rag.  

4.  The high mass wood stove is something I gave a bit of thought to as well.  Depending on the material you choose to build with and it's denisty (thermal mass) a quick to heat up stove might work as well.  Just as an example my house will use a reg steel stove for a variety of reasons but with the amount of insulated mass we have I feel that I would rather have something that heated up the air quickly.  Once the air is warm the cooler mass of the brick walls etc will absorb some of that heat.  This accomplishes the same goal of storing that heat and releasing is back into the room.  Now if you have a straw bale with no mass then a high mass wood stove would be a great idea I think.  Given that storing heat in air is a inefficient method.

5. I'm not a big fan of forced air .  I'd recommend being that you state that your using a slab to use radiant tubing in the slab.  This allows you in the future to possibly hook it up to a solar water heater and run it through the slab.  Storing heat in mass is a much better way then in the air IMHO!

I hope this helps some.  I know i was in the research stage and saw all these options as well.  Sometimes though trying to combine to much just makes for a overall more expensive system that will cost more in the long run.  Simple is best  These are my opinions as it's hard to get an idea what would work for you.  Your on the right track after a bit longer you will figure it out in your head.

GL...and we just finished up with our last blocks for a while today.  So tuck will have to wait till the retaining wall before he can help stack!

[drainl]

Update on House Finances

I had about 3 months of receipts to add up. Luckily there weren't too many! We didn't have any major purchases. We got our wood stove ($500) and 3″ 4×8 foam insullation sheets ($320). We got a great deal on a display model shower door - $10 marked down from around $250. For freebies, we found two interior solid wood doors, one wood framed screen door, and a sink for the bathroom. Here's our current totals. This will jump quite a bit as we begin to buy roofing supplies.

Electric $1,513.80
Materials $6,444.10
Miscellaneous $1,907.28
Paid Workers $30.00
Plumbing $518.57
Roof $609.89
Septic $1,000.00
Site Work $6,019.17

Total $18,042.81

[drainl]

All the blocks have been stacked (for now) and all the window are framed out. Phew! We've had some pretty great weather considering it's November. We might just get this roof on afterall! The last house we built we started building in November, so we know what working outside in the winter is like and we don't want to repeat it.





Jeff trying to avoid buying another stick of rebar...







Jeff putting on a batch of SBC in the bedroom. This is where the roof line of the bedroom will hit the wall, so he wanted to get the SBC up first.



We're excited to be done working with the blocks and concrete for now. On to the roof! We're going to try and get the bedroom roof framed out tomorrow. Jeff will place an order for the 2″x12″ wood for the larger roof on Monday. We're hoping to have friends over next weekend for framing the big roof out. We're putting up 1″x6″ T&G pine for the roof sheething.  Can't wait to see the roof line!

[Redoverfarm]

drainl are you not worried starting in the roof before the SBC has been applied? Structurally I mean.

[speedfunk]

Hey Redover.

Nope we are not worried.  The reason being is that there are vertical columns of concrete and rebar every 4' and then the bond beam .  I feel it's plenty strong to keep working.   Of course backfilling is a different matter. 

We wanted to have the surface bonding cement done but it is what it is.  

[drainl]

We (mostly Jeff) started the bedroom roof on Sunday. First thing to do was put the sill plates on (non-pressure treated 2″x8″), along with the foam barrier. Drilling out all the holes for the bolts took a little time. I worked on sanding the boards, getting the writing and stains off. Everything will be exposed, and it’s much easier sanding it on the ground then above your head.



Jeff rigged up some boards to hold up the main beam. He’s basically done this whole roof by himself, so he didn’t have me to hold boards up for him. Makes everything go a little slower.





The angle of the bedroom roof is similar to the back of the main roof. Once he got a template figured out, he started on the rafters.







Then he trimmed up the ends and started putting up the T&G. We ended up with 1″x8″ boards from a local lumber yard. They were just put on the pile when Jeff got there so he had prime selection.





Jeff finished up the boards and got Typar on yesterday before it rained all night. Finally - a dry room in the house!



This board is for support on the outside wall.




Today Jeff hoped to finished the outside wall with the T&G along with each end. Then we're wrapping it up tight and leaving it to move on to the bigger roof. We're borrowing scaffolding from a friend and will hopefully have some help this weekend to get the main beam up along with the 2″x12″ rafters. We've really lucked out with the weather, but today it was beginning to get cold again.

[Sassy]

Making great progress - dry rooms are good   

[Dog]

Looking really good guys! Those boards are beautiful.
Happy Thanksgiving~

[speedfunk]

Yup turkey day is coming.  To honest I've almost forgot. Trying to get someone here thrusday to help finish up the main ridge beam which we have now partially done.  Ron said it's thanksgiving thursday...  Oh YEAH....lol.

Thanks!!  The pine boards too will be left open like that .  There will be no insulation put in the bays.  It will go ONTOP of the typar.  I love pine   to bad it yellow a bit b/c when it's fresh it looks and smells awesome.

happy turkey days!!

[speedfunk]

Speaking of pine.  Is there anyway to treat it (besides poly) so it doesn't yellow.  something like a wax maybe?  Something that you can rub in rather then brush on?

[MountainDon]

The only thing I know of that does not yellow are the clear coats like Minwax Polycrylic. They're water based and milky when wet. Everything else I've used over the decades yellowed or had other problems. I haven't tried everything, maybe someone knows of something else.

[EcoHeliGuy]

i only use linseed oil (wiki) it made from flax, and in 100% natural, it penetrates the wood, not coats it, so with soft woods you need more coats, I have not tried it on pine, but it is yellow by nature, it really brings out the grain on the wood, and no fumes.

[speedfunk]

thanks Don and Eco for your thoughts on treating the pine

We have left the pine un-treated in our First Day cottage.  It's not bad mind you.  I like it ..I just REALLY like the fresh,white look of the pine. 

I found this I'm not sure how it works though


http://www.wood-you-like-diy.co.uk/acatalog/Fitting_&_Finish_Materials.html

[drainl]

We're not quite where we'd like to be with the roof, but we keep plugging away as we have time. The weather is colder (30s) but we haven't had too much rain. We have made some progress though - the bedroom roof is finished up to the Typar and all taped up. Dry storage is great!





The sill plates are all up and bolted on for the large part of the house:


The trees have been notched and the beam is in place. Our friend Ron came over to help get the beam started and Jeff's brother Ben came over to finish setting it. I say beam, but it's actually two 32′ LVLs.






T enjoying dinner on his new chair and table



Here's the beam bolted together and sanded down. We wanted to leave the beam exposed, but it wasn't looking too pretty. Jeff put a stain on it tonight which should do the trick! The trees will be trimmed down to be flush with the beam.




We've got all the 2″x12″ boards for the rafters at the site and about half are cut and ready to put up. Jeff went to the lumber yard to hand pick them, but they aren't all great. I'm trying to get them sanded down before we put them up to avoid having to sand overhead. I'm only about a third of the way through the pile though.


So that's all for now! We'll have at least one full day with both of us at the house this week (and no little guy). Putting the rafters up is a two person job and finding days with us both able to work is tricky.

[drainl]

We got our first snow fall last night - our main roof isn't quite leakproof yet so we spent some time cleaning up before we started working. About 1/2 of the rafters are up and tacked in.

The first rafters (and first flakes)


The roof line




Jeff used the thin board to slide the 12′ boards on the back side of the house. Worked well for a one man job. The 18′ boards take both of us.


The East side of the house

[Sassy]

Brrrrr!  Looks like you were working in some pretty cold weather!  Great progress    I'm looking forward to seeing those big log posts when you get the roof on that part - that will be a nice feature in your house.

[drainl]

Thanks Sassy!

We keep on plugging away on the main roof - most days at least one of us is on the site. 35 and sunny sounds like dream working conditions right now. Instead we've had cold (20s or less) and sometimes wind and rain. The joys of working outside in the winter!

All the rafters are up. We started off just tacking them into the beam, but with high winds a few pulled out, so we got them bolted together at the top as well.





A couple rafters hit our trees, so Jeff had to trim them out with a circular saw and chisel.



Then the front of the rafters were nailed in, trimmed and sanded clean. The T&G along the front helped keep the rafters straight.



After double checking all the rafters, we started with the T&G - woohoo! It's always nice to see a new part of the project start. Especially a highly visible one like the sheathing! After some bearable sleet and snow, the cold rain (and soaked clothes) finally convinced us to head home for hot showers. The T&G went up pretty quickly with the two of us. We're hoping to get some more up tomorrow.

[speedfunk]

Thanx deb for posting!  


Things are going really well.  As we went along installing the rafters we kept a couple tongue and groove pine boards (approx 8' or so) so that we could constantly check to make sure that the decking was level.  Tip. When cutting the rafters boards from the template focus more on the top part of the board then the bottom.  I didn't do this at the beginning of the rafter cuttings but adjusted by the end.    

The boards for the rafters  were the best we could get but some were twisted a little. So by first tacking the down the rafters to the sill plate and then using a level on the rafter boards to make sure the were perpendicular to the sill plate.  We used the T+G pine board on the side of the house rafters in place before nailing on decking.  

The top pic of this post shows the rear part of the rafters .  I just wanted to add that they are not nailed down on the north (back wall) sil plate yet.  So if they look uneven they are!   

Edited to add that I have a shit load of respect for all the amazing woodworking some members have done!  Wood requires patience and understanding of types and grains of wood.  I try my best to make things clean but sometimes it looks like a first time house builder wackin' on some nails lol.

[Beavers]

Looking good Speedfunk! 

I really like the exposed rafters.  How are you going to put the insulation on top of the T&G ? 

Sorry if you already explained this, and I missed it.

[Dog]

Wow! You guys are really moving right along. The wood looks great!

[speedfunk]

I'm not sure if I have meantioned to be honest.  It's going to have 5"'s of rigid sheet polyiso insulation on top of typar covered decking.  This will connect with the 4"'s of rigid insulation on the walls.  So in theory there will be no gaps in the insulation envelope.  There will be purlings (I think that's the spelling ) to screw the metal roof to.  We are leaning towards a standing seam roof.  This will allow the roof to  overhang the the walls a couple/few feet with no/very little support.

THanks for the kind words beavers.     I really want to make sure the rafters were exposed.  It goes with the way we are building to keep the construction details exposed and "celebrate" the way it was built and the materials used .  

Thanks Dog too! (editing to add!)

[rick91351]

Hey man, you guys are earning a lot of respect on this forum.  You walk the walk man.