The experiments are over

[peternap]

Over the last year, I've built a dozen mini rooms and a couple sheds to play with insulation.

I have come to the conclusion that 3 dead air spaces with zero air infiltration in walls (ceiling is different) and no wall studs (Timber frame) is a better insulation than fiberglass. Since It's about time to get the walls up on the barn, I need to fish or cut bait.

That's how I;m going to build them.

[mvk]

Peter
Is this a barn barn or a heated living space?

There was a book years ago Your Engineered House I think, which advocated 3/4" air spaces and reflective foil on a 4x4 frame. It had layer's of 1by  reverse board and batten, horizontal strapping then reverse board and batten with the foil in between.  It was pretty popular with the DIY movement. Lots of cold house's in NH though. I liked the book by the way there was some good stuff in there just the insulation detail didn't work.

What did you have in mind? What kinds of test did you do?

Mike

[muldoon]

Peter,

Sorry for the dumb question but I cannot exactly picture what you described.  Could you be a little more descriptive about your approach here?  What are the layers in the wall?

sheetrock
vapor barrier
framing
vapor barrier
siding
??

What materials did you use in your most successful experiment and how significant are the results?

[peternap]

MVK, it's a heated living space. It works on the test rooms I built here. It has to be tight though.

[mvk]

peter
Whats your wall section detail? I have the same questions as muldoon. Always looking for a new idea.
Mike

[peternap]

Muldoon, it's a pole barn (timber frame) frame. The center chamber and the largest is the space created by the 6x6 poles.

The outer space is between the girds and poles.

The last chamber is inside between the poles and nailers.

I tried a builders plastic, felt, Tyvek, paper, bubble wrap, swimming pool cover (Reflective), plywood and inflated trash bags.

All had one problem or the other but the worst was condensation on the builders plastic.

What I've settled on is felt on the outside of the girds and the edges breaking on a gird, using roof coating to seal the joint.

Tyvak on both sides of the poles and felt again inside on the nailers. Over that is pine planking I sawed.

The outside gets something...(I haven't decided yet).

I've already made the windows, shutters and doors.

I tested the rooms by putting a 100 watt light bulb in the fiberglass room (4X4X8 box) and in the room with different combos, and measured the temperature
at the ceiling.

Played with it on and off all winter.

The combination above equaled or beat the ceiling temperature of the fiberglass.

[peternap]

Sorry MVK, you beat me to it.
BTW, this did NOT work well with wall studs. You need a tight, empty space with no drafts.

[NELSELGNE]

SEE:

http://countryplans.com/smf/index.php?topic=2111.msg19838#msg19838


Improved board and batten siding method.

from: YOUR ENGINEERED HOUSE by Rex Roberts

free online at:

http://www.soilandhealth.org/03sov/0302hsted/030211Roberts/YEHtoc.htm

see: HOW TO BUILD A WALL  at:

http://www.soilandhealth.org/03sov/0302hsted/030211Roberts/YEH04.htm


This is the board and batten you are thinking of, with the board put on first and the batten showing on the outside. It looks cheap, and is. All 1 do is turn the board and batten around:

Nail the battens to the framing and the siding boards to the battens.  By doing that you add another inch to the effective stiffness of the wall, trap another inch of air, provide a free drainage channel for the dew. The whole thing remains cheap, but it looks expensive.

note: Some of his methods have been effective and others have not.

eg: the aluminum foil insulation.

a revised edition by Charlie Wing is available.

see: http://www.amazon.com/Rex-Roberts-Your-Engineered-House/dp/0871315335/sr=8-1/qid=1160137571/ref=pd_bbs_1/102-1787687-4574565?ie=UTF8&s=books

[mvk]

Yup that's the book, guess I should check the archives more. Had some friends who built like that years ago boy were they some cold houses. Used to have that and the charlie wing book can't find a lot of books though lent them out and they moved away, some are in Montana I think?

Still like the reverse board and batten, like how he laid out a house, raising in the east ( I'm a morning person), also liked the Idea of bedrooms on the ground floor for fires. Glad it's online have to read it again to see what I remember and what I forgot or got wrong?

Mike

[Redoverfarm]

mvk  I have a barn well it was a house in the early 1900's, I think it was "jenny Lind" style.  Sort of like the reverse B&B, There were no studs only wide batten strips with the boards nailed onto those for the outside sheeting.  I think that it what they called Jenny Lind style.  Pretty strong in fact I moved it (15'X30') with a dozer when I built my house(original barn site) approximately 200' with shag bark hickory poles.  There was a 15'X30' wagon shed attached which I managed to move with it and it stayed together amazingly.

[CREATIVE1]

I have a 14 x 45 foot 2 story pole barn I want to partially enclose.  I was considering a timber frame/Japanese look, with hardiboard panels between the vertical and horizontal studs.  Some of it will be outside living room, some storage, and some guest/living space.  This is an interesting thread with some ideas we might be able to use.  I have to go totally standard on the house, but can do ANYTHING with the barn.  Will be working on it after all the officials go away.  And no one can see any of our property from any direction, sooo    Peternap, in what sort of climate did you run your experiments?

[peternap]

I have a 14 x 45 foot 2 story pole barn I want to partially enclose.  I was considering a timber frame/Japanese look, with hardiboard panels between the vertical and horizontal studs.  Some of it will be outside living room, some storage, and some guest/living space.  This is an interesting thread with some ideas we might be able to use.  I have to go totally standard on the house, but can do ANYTHING with the barn.  Will be working on it after all the officials go away.  And no one can see any of our property from any direction, sooo    Peternap, in what sort of climate did you run your experiments?

We had a pretty mild winter. 30's and 40's mostly.

The idea was to see how the membranes compared to fiberglass with the same heat source. I got the idea because I use a 100 watt bulb in my pump house to keep it from freezing.

[NM_Shooter]

Hi Peter, I've been watching this with interest and have been wondering about something.  It would seem that unless the chambers are evacuated, you would still get some convection that would would make the top hotter than the bottom.  Or the bottom colder than the top.  Take your pick. 

Anyway, the good thing about insulation, is that it slows down convection in the wall space that leads to hot or cold spots inside the cavity.  Or is it cheaper to just build another wall section than to insulate?  I would think that hot air would collect at the tops, and with no insulation to slow it down it would radiate through like crazy.

A buddy of mine did an interesting technique on his walls.  He used a 2X6 top and bottom plate, and used 2X4 studs on 24" spacing inside and out.  He staggered the inside and outside sets of studs so that he then had them basically on 12" centers.  This provided him with a 2X6 wall with no stud conduction.  (actually I don't remember if it was 2X6 or 2X8, but same technique).

Then he put foam on the outside of the wall, with a radiant barrier facing outside, and a vented board and batten covering over the whole thing.  He said that his west wall stays very cool in the summer.

[MountainDon]

What's needed is a perfect seal and a vacuum in the walls. No air = no convection, no conduction.

I read somewhere once about what is the ideal spacing for air insulated spaces. It's actually fairly small, well under an inch IIRC, but I don't recall exactly nor where I read it. Convection currents will start to move heat from one surface to the other when the spacing is sufficient. That probably gets more pronounced as the temperature differential of the surfaces increases.

I read about walls like what Frank described someplace too. Seems to be a good method of achieving much better than average performance.

[phalynx]

How about tubes of water between the wall layers? 

[MountainDon]

Water is a poor insulator. It can provide thermal mass and as such in effect slow down the rate of heat transfer from one side to the other. Of course if the interior space was unheated for a while and the outside below freezing it would eventually freeze.

[glenn kangiser]

What Don said but they can be great for early heat storage in the garden - starting tomatoes etc.  Called  Wall-o-water I think.

[eric]

This is a great thread. The 2x6 top and bottom plates with staggered 2x4s at 12" oc is interesting. If you put 1.5" thick by 12" wide pink foam board in the very center of the wall and 2" thick by 24" wide pink foam board on the inside and outside of the wall you'd have no airspace/convection issues and some serious r-value (like 27? not counting the studs) in a 5.5" wall without stud conduction.

I hope that came out right.

Is there provision for a wall like that in standard building code? Or rather, do you think they (as in "them") might let me do that?

[MountainDon]

Nothing akin to that is listed in any code I've seen. It would be a case of showing "them" what is proposed and having "them" bless the design. I would think it should be possible.

To fill the cavity with cut foam board as you propose would be labor intensive and require great care to seal the panels in place to prevent the dreaded air movement within the wall cavity. This might be an ideal situation for blown in wet cellulose; of course that would entail the use of an insulation contractor willing to deal with an unconventional idea. Or spray in Icynene; expensive though.

[Willy]

This is a great thread. The 2x6 top and bottom plates with staggered 2x4s at 12" oc is interesting. If you put 1.5" thick by 12" wide pink foam board in the very center of the wall and 2" thick by 24" wide pink foam board on the inside and outside of the wall you'd have no airspace/convection issues and some serious r-value (like 27? not counting the studs) in a 5.5" wall without stud conduction.

I hope that came out right.

Is there provision for a wall like that in standard building code? Or rather, do you think they (as in "them") might let me do that?

This is done in apartments/condos all the time for sound proofing reasons between units but I have never saw it done on a outside wall. Mark

[NM_Shooter]

I used the blown in batting system (BIBS I think it was called) and was really impressed with the installation.  The insulation folks came and stretched a porous membrane accross the walls.  Then through a series of slits, they blew in the insulation.  I was worried that it would settle over time, but the compression was pretty good to start with.  My walls had a "quilted" look.  The accoustics of the room were spooky when that was first installed .  I placed 2" foam on the outside of the house too, so my walls are pretty well insulated.  I'm guessing close to R29.

They had a kid on the roof blowing in insulation as well.  He was supposed to fill in to 18 to 22 inches if I remember right, but he got left alone and must have been daydreaming.  I watched him fill the pocket to 36" of insulation near the eaves.  I thought he was overfilling to compensate for settling, but after the boss got back and he yelled, I realized I got a deal.

Here's my new BFF.  The wall that he is standing on is about 42" above the ceiling in the room below.  Let it snow, let it snow, let it snow!



I'm mostly worried about cooling costs.  I think Peter might have the right idea with multiple wall sections, but I think the outer one should have a radiant barrier and be vented (for cooling purposes).  But I think all his tests were for heat retention if I read right.

[mvk]

shooter
I'm interested in bib's and would like any information, cost, why you chose it, did you compare it to cellulose? I'm thinking of cellulose mostly because I can DIY. Still not sure, it's either foam and batts like Mountain Don, or a trussed wall  (double wall) with cellulose right now? We have some set backs and I think foam might really go up in price by the time I can build. I was thinking 2" of foam. Think SIP's are just out of the question because of price though every time I see some pictures like your place I kind of wish

Anybody use that spyder stuff, think Glen first posted about it, seems like BIB's with out a bag?

Mike

[NM_Shooter]

Sorry, but my insulation job was based on a lot of work... I had them insulate the whole structure, and do soundproofing between rooms too.  I wouldn't know how to break it out. 

I did shop around a bunch and found a local place (Duke City Insulation) that gave the best price.  I was terrified that I was building myself a much larger utility bill so I over-did the insulation.  It is amazing how little it takes to heat and cool it.  I have a wood stove in there that heats the 14,000 cubic feet of space from cool to uncomfortably warm in about 20 minutes.  I should have put in a much small stove as you can't seem to burn any fire in it for a long period of time.  But I am okay with screwing up on that side of caution.  This is probably a great application for solar hot air.

I probably spent $2000 more in insualtion than I could have (BIBS plus exterior foam).  Sort of like a PV solar system, whoever gets this after me is going to get a deal.

-f-

[John Raabe]

BIBS is a great insulation system. I've used it for years here in the NW. Looks like shooter has a snug project.

About the staggered 2x4 studs on a 2x8 plate. That is the wall system I did in a custom house near Greenbank on Whidbey Island WA. The owners cut much of the wood from the site and we had no problems with the codes or inspectors. It is a very sturdy wall system. Virtually all of the wall is insulated with little framing loss through the wood.





I think the owners (who are doing most of the work themselves at this point) are planning to do BIBS insulation.

[peternap]

I mostly worried about cooling costs.  I think Peter might have the right idea with multiple wall sections, but I think the outer one should have a radiant barrier and be vented (for cooling purposes).  But I think all his tests were for heat retention if I read right.

NMS is right. I'm interested in heating only and not overly interested in that. I will have wood heat in one open room. Wood is cheap as in free for me and more efficient than other types.

Since I'm off grid, AC is out except on very hot days and then, only in the bedroom.

Even the ceiling only gets 2" of insulation. The center section is 8' higher than the sloped ceiling in the main room. Heat will gather there and can be recirculated back down.

As long as I keep the air infiltration to a minimum, it will work fine for me. I can't say it is what anyone else needs.