Okanogan 14x24 by a lurker :)

[OlJarhead]

Playing with sketchup today and while the terrain model isn't quite right it's close...just can't figure out how to excavate in it though.


Would have to move that generator up a little and put some brick around the back and outside to protect it from cows and will have to put a roof over it so snow doesn't bury it coming off the roof.

[OlJarhead]

Last one for now

Fixed the terrain a little and moved the generator up a little to where it will most likely be.  Added the vent for the heater too.

[OlJarhead]

I've begun now to consider doing a double wall room for the composter room.  My thought is as follows:

1.  Pour floor (possibly insulate under it first)
2.  Build up dry stacked and surface bonded cinder block walls to above ground level
3.  Frame and sheet 2x6 exterior walls (R21 insulation) with no penetrations except where the vent for the heater will go.
4.  Build 2x4 interior wall (R13 insulation) and wire in void between two walls.
5.  Insulate interior side of exterior door.
6.  Frame and insulate double 2x4 walls under cabin to keep crawl space well insulated and place rigid foam on ground in crawl space to increase insulation in extreme cold.
7.  Double insulate duct passage from behind wood stove to crawl space and composter room.
8.  Roof composter with at least 2x8 rafters (I'm limited here because of placement and depending on depth of floor but think I might be able to use 2x10's if done right) and get R30 to R38 insulation in the ceiling.

My goal is to make the composter room and crawl space as well insulated as I can possibly make it so the heater doesn't have to actually run that much, just enough to raise the temp to above 50 degrees and then be able to maintain that without constantly running.

[OlJarhead]

Another consideration is that I'll have a generator backup and if I wire that into an AC panel I can then feed the room with a 120v receptacle and plug the composters dehydrator/heater into that as well as the inverter charger -- both on separate breakers/legs.

This way when the generator runs the composter AC fan and heater will also run which has the added benefit of helping keep it warm as well as rid the system of excess moisture.

I plan to install a dry sump instead of the standard french cesspit and will probably install a drain the floor of the room also.  This way should something go wrong and the composter drain plugs and backs up the waste water can go somewhere and the floor can be washed down and cleaned without worrying.  I'll probably have to paint the concrete with something too but that might have to wait.

One last benefit this room may or will have is that I could always put a 55 gallon water drum in the room with the RV pump setup I now have.  That way if something goes wrong with the water lines coming into the cabin from the cistern I'd have backup water and a heat sink in the room -- the 55 gallon drum of water will be warmed by the heater and will take a long time to lose it's heat so will provide the added benefit of a heat sink.   Something to ponder anyway

[MountainDon]

I've begun now to consider doing a double wall room for the composter room.  My thought is as follows:

1.  Pour floor (possibly insulate under it first)

My goal is to make the composter room and crawl space as well insulated as I can possibly make it

Re: 1.    not possibly... Just do it

Re: the goal... use rigid foam. Single 2x4 framing for walls, sheath osb and apply rigid foam on the outside. The osb to offer fire resistance for foam or better yet apply type X sheetrock inside the framing with foam on exterior. Don't bother with batts in the framing cavities. Then screw furring strips into the studs and over the foam vertically and apply lap siding from your sawmill.

Ditto the roof; 2x4 is likely strong enough. Foam on top of osb, then another osb layer and the roofing material.


The heater may provide enough heat with just the pilot going.

[OlJarhead]

Not sure I understand -- let me try:

1.  2x4 walls (single not double)
2.  5/8" OSB exterior sheathing
3.  2" R12.9 Thermasheath 3 exterior foam sheathing on the OUTSIDE of the OSB
4.  Furring screwed through foam into OSB
5.  Lap Siding exterior
6.  NO insulation in the cavities (so an air pocket)
7.  Sheetrock interior

You think that's enough?  It's an R12.9 wall plus sheathing and drywall but why not include the R13 or R15 fiberglass also?

Re: the roof -- 2x4 on a 3x12 or 4x12 pitch would be too weak with the snow load without the steep 12x12 roof above dumping on it.  I'd think maybe 2x8 would be ok but pushing it.  Not sure I understand why an R12.9 would be enough?  Wouldn't something more like an R30 do better?

I like the idea of the pilot light keeping it warm enough!

[OlJarhead]

Looking at insulating techniques for the floor and cinder block walls has led me to think this is the way to go.  Basically put down some 6 mil (10mil if possible) plastic on the ground and cover with foam insulation (R10-R12.9) then place exterior foam (R12.9) on the outside of the cinder block walls to a level below glade down to the floor and below. 

Siding would have to go down below the insulation so I'm not sure how that's done to hide the insulation and still protect from bugs and water....but I'll do more research.

[OlJarhead]

And of course fill the voids with concrete and/or soil (I've read you only need to fill every 2nd or 3rd void depending on wall height, with concrete and the rest can actually be soil as long as it's sealed -- think thermal mass). 

I'm thinking that if I insulate the floor and walls well enough then I ought to be able to keep this room warm despite the exterior temps which can easily drop WELL below zero.

[MountainDon]

Fiberglass batts offer the potential for more heat leakage in nooks and crannies for one thing. Rigid foam, seams taped and maybe caulked with the right material offer the most air IMpermeable insulation. Also seems to me that building multiple frameworks is more work.

1.  2x4 walls (single not double) [[simple to build and as long as extra thickness is not needed for something like a DWV pipe in a home wall for example, it is all that is needed.]]
2.  5/8" OSB exterior sheathing  [[1/2" is enough]]
3.  2" R12.9 Thermasheath 3 exterior foam sheathing on the OUTSIDE of the OSB [[2 layers, seams staggered offers greater ease of air tight sealing.]]
4.  Furring screwed through foam into OSB  [[NO, into the studs. Use Headlok screws. ]]
5.  Lap Siding exterior
6.  NO insulation in the cavities (so an air pocket) [[just because it's simpler to leave it out.]]


2" R12.9 Thermasheath......   their listed R-value includes an assigned R 2.77 value when using a 3/4" dead air space.  That is the theory; I am not certain it follows in actual real world practice in all cases. In a vented rain wall for example the air space is not sealed, not dead air.


FWIW, if I was building a new cabin/home now I would skip the insulation in the wall cavities altogether and go with multiple layers of exterior foam.

[OlJarhead]

OK I think I'm tracking.  So what you are advocating is 4" of foam exterior foam insulation (R20-R25..

So if the exterior foam was sealed/taped etc and the void was filled with R13 would that not be almost the same?  I ask because of cost.  Not that I can't afford the foam just always looking for ways to keep costs down.

2x4's are easier on me since I can turn all my 2x8's into 2x4's   and I can use all rough cuts (seeings I made them myself).

I guess I'm having a hard time with the voids -- seems like a lot of foam on the exterior.

[OlJarhead]

http://www.hgtvremodels.com/home-systems/foam-sheathing-on-exterior-walls/index.html
interesting short article.

Seems using the R12.9 on the outside of the wall sheathing, then furring and siding with lap siding while using fiberglass on the inside would work too. 

Using 2x4 walls has the added benefit of making it easier to solve the thick wall issue of installing a door because the 2x4 wall will be closer to the 2x6 door framing

I'm planning on an exterior door with good gaskets and maybe even insulating the interior of it though that might be going overboard!

Using the foam in the crawl space would be much easier and doing it on the outside of the walls would be simple enough too -- and I wouldn't have to worry about weather.

[MountainDon]

Plus the foam sheets remove the heat bridges the studs provide.

One layer of foam and some batts will work. The foam makes it a lot better. I have handled enough batts over the years to develop a personal fiberitch neurosis. My personal problem.

If building a concrete block wall don't get caught up in the "need" to take advantage of thermal mass. In some ways it is overblown and in some ways can work against you. IE, if the mass is now cool and the space needs to be warmed the mass is a negative.  OTOH, once the space is warm and fossil fuel is being used to maintain the temperature, there should be no advantage to having more mass. Mass would be important to have if you were building a solar collector to provide heat for the composting space. 

Foam can be glued to the inside of the blocks. Foam can also be applied on the interior of the 2x4 framing and then sheetrocked for fire value.

[John Raabe]

Ditto on the thermal mass. It acts as a flywheel and that can be a disadvantage in a cabin where you will be visiting occasionally and where you would like to bring the temp up quickly. If you are blessed with good sun during the heating season, the mass can then soak up heat when you can use it. But many places won't get enough sunlight. At my home in not-so-sunny WA the sunroom, with all its thermal mass, doesn't get comfortable as living space for about half the year. It never freezes, but you don't lay around in it when it's cloudy and 45-50º out there.

[OlJarhead]

Ditto on the thermal mass. It acts as a flywheel and that can be a disadvantage in a cabin where you will be visiting occasionally and where you would like to bring the temp up quickly. If you are blessed with good sun during the heating season, the mass can then soak up heat when you can use it. But many places won't get enough sunlight. At my home in not-so-sunny WA the sunroom, with all its thermal mass, doesn't get comfortable as living space for about half the year. It never freezes, but you don't lay around in it when it's cloudy and 45-50º out there.

But this is about making it a place to live in.  I may be taking a position with a major Telco in the area and if so I'll be living full time at the cabin for a while -- 2-3 years possibly.  So the idea is to address the issues you don't have to when temporarily staying at the cabin.

[MountainDon]

Re: thermal mass, flywheel effect, full time residence use........

IF the fuel source is something other than solar, I do not see any advantage to incorporating a thermal mass in the compost toilet collection drum chamber. Thermal mass is effective to temper the temperature swings with direct solar derived heating. If a fossil fuel is used (propane, nat. gas, kerosene, etc...) there is no advantage to having thermal mass. As long as the heater keeps heating the mass just sits there and contributes nothing. The propane heater in question will still automatically cycle on and off with more or less the same rhythm. Only adding insulation, slowing down the heat loss, will reduce fossil fuel use.

If OTOH, you had an air or liquid solar collector and were heating the mass during the sunny daytime, then the thermal mass could make a lot of sense. I'm just thinking of saving trouble, time and maybe some cash if the fuel used is fossil. At least I can not see any advantage in that scenario. Maybe I can't see the forest for the trees?

Unless you might add a solar collection unit at some date.

[OlJarhead]

Good point Don -- so in the cinder blocks put nothing?  Except the voids that must be filled?  This will be a surface bonded (dry stacked) wall.

[OlJarhead]

https://www.thenaturalhome.com/drystackblock.htm
This is what I planned on doing for my cinderblock walls.

[MountainDon]

If going to the trouble, effort and expense to keep the poo warm, what about incorporating a warm place for the batteries?

[OlJarhead]

If going to the trouble, effort and expense to keep the poo warm, what about incorporating a warm place for the batteries?

That's part of the plan   First step is to fully insulate and complete the porch, then I'll add a covered 'deck/porch' in front of that and finally I'll put in some air vents, perhaps even with fans, to allow the wood stove to warm the porch in winter.  Not sure I'd do more though but with all the windows it's stayed 10 degrees warmer in the porch, in winter, then outside even without insulation.  SO I'm fairly certain with a little work insulating it I can keep it 50 degrees or so and the stove is more then capable of heating the added space  

[MountainDon]

I was thinking along the lines of the batteries being in the compost bin area...

[OlJarhead]

You know Don that would be a good idea.  I pondered that for a moment when I first started this exercise but then forgot about it.

It would free up the front porch complete and negate the need to warm it.  Only issue I can see if that I'd have to run an additional 16-18 feet of wire from the solar panels to the batteries but that shouldn't really matter since I'm just about 50 feet now and since I run about 60vdc rather then the 48vdc I calculated the run on I'm sure I have some fudge factor.

This would of course give me a LOT more room in the porch.

Hmmm to think about it for a few, after all, I'd have to run the AC wire from there to the panel which would be fine since it wasn't inside the walls anyway (goes from inside the wall down under the cabin over to the porch).  Only thing I can see that I would need to do would be to run AC to the porch but I could do that under the cabin easily enough and pop it up into the all that's not finished.

Of course then I would need a remote sensor for the charge controller and the batteries but that's not too much.

With the heater in the composter room it sure makes sense doesn't it?

[MountainDon]

With the heater in the composter room it sure makes sense doesn't it?

....more birds with one stone sort of thing   

[OlJarhead]

Yep   Thanks Don, great idea!

I might have to add a couple feet to the room but perhaps not -- after all I could make a shelf to put the batteries on which would raise them off the floor and stack them two shelves high (4x4's ought to be strong enough with 2x6 flooring).  Would keep them from taking up too much room and ensure I get the most power out of them throughout the year.

[OlJarhead]

Big day tomorrow! 

If my in person interview goes well then I should know by tomorrow afternoon if all of this is going to be a reality.  As such I'll admit I'm not sleeping well.  LOL  My mind goes 100 miles an hour when it's locked onto something and right now it's improving the cabin.

With the compost room design nearly done I've been contemplating concrete work (do I put in expansion lines in such a small slab?), floor drain (thinking of a center drain because one never knows -- specially with a composting toilet in the room), running 1" drain line from Dry Sump to where composter will reside, installing new sewage pipe and toilet flange (Sunmar has one they recommend, the one I used was not overly stable but worked -- it was an HD flange with the sunmar gasket which I think was too thick causing the seat to rock a bit), putting in the crawl space enterance and possibly sealing it so the heater doesn't have to heat it up too and then running duct from the cabin stove area to the crawl space and so much more!

At least some things have been resolved like running main water line:  with composter removed and a new excavation going on for it's room it will be an easy matter to install the water line before putting in the floor and foundation and we should have no problem trenching the line in deep with the excavator (added bonus being that it won't rise before coming up into the cabin thereby giving us the very best water pressure we can get).

ya, the mind is racing...and tomorrow it will either become reality or won't....hang on!

[UK4X4]

Good luck for tommorow !