Insulating Rafters

[Sassy]

I really like your place!  Really cute & the views are wonderful!

[bartholomew]

I vote with JRR on this one -- insulate with foam board on the outside. As John M says you'd probably want more than an inch or two of insulation for full-time living. Yeah, it'd be a shame to tear off an almost new roof, but it would also be a shame to cover up that nice ceiling. Cutting boards to fit between would be a pain and won't look as good. Nice place!

[jraabe]

Notice the framing of this cabin. Maybe we've been worrying too much about the outward thrust of roof loads?

If I read the photos right, there is something like a 2' to 3' high stem wall in the loft (and where the bridge is the loft does not tie the walls together). On this wall sits the low-slope rafters with no collar ties to triangulate the downward and outward forces on the rafters as the snow builds up. All this is transferred into the walls.

And the walls are something like 6x6 cut logs, correct?

PS - Now that I see the cabin look of the exposed wood, I concur on putting the foam on the outside of the roof sheathing and leaving the framing exposed on the interior. I would also go to a metal roof to cut down the snow load the roof will have to carry.

[mike lopiccolo(Guest)]

Hunter ,,,great place..... is that the catskills....near Deposit ny?

[bartholomew]

Wouldn't a log wall have much greater strength against sideways loads than a framed wall? With the log kits, the logs often have kind of a tongue and groove connection, so it's not just the top log taking the force alone. The wall would act more like a 6" deep by whatever wide beam resisting the sideways force.

[Okie_Bob]

Peg a couple of posts back you mentioned a spray in foam and couldn't recall the name. Was it Icynene? I used this stuff in my garage/apartment and love it. Will use it again in the house for sure. The guy that I used to install it tried to talk me into going with no ventilation in the attic at all. Says that is what they recommend. I didn't, I have soffet vents all around and a fan on thermostat control in one gabled end. Wish I had gone ventless now and plan to do so on the house. House will have sissor trusses and plan to fill them up with Icynene and then cover with pine planks.
Loved the loft and the entire cabin! And Glenn, thanks for the pics, they are super but, dang I don't know how people live in that kind of cold! (I know, it's probably dry cold so it's like being on a beach!)
Okie Bob

[jraabe]

Yes, a ventless roof is probably the way to go (in most climates anyway) when you do a spray foam like Icynene. It does such a good job of airsealing that moisture can't get to the cold surfaces to condense.

For specific climates, check with the local installer and/or the building inspector. More and more jurisdictions are following the latest research that shows ventilation over the insulation in roofs can, in some climates, be counter productive.

[hunter63]

I am enclosing a pic that shows of the lost joists, there is a short wall in the loft.
In some of the older models thet used flat wall logs, there was a concern on spreading, usually in the one without the double lofts. We have been keeping an eye out.
Joists are 4"x6" and the logs are 8"x8" milled in a "D" w/tongue and groove interlocks on the inside, and rebar.

You can see my concern in the pic, on the insulation as the snow melted off the roof, in side the wall (heated area.)

Stove (Stewart) was built in Milwaukee, but haven't had much luck on finding information on it.

It was Nat.Gas and I converted it to propane, quite a process as the orifice had to be soldered shut, then redrilled to spec's from the National Gas Code. This is done w/  index drills and chart.
Need to find out what size the orifices were ,then look up B.T.U.'s for thet size for N.G. then use the chart to determine the new size.
Not exact, but real close.
Need to drop the burners size a couple of .001's as I am getting a slightly lazy flame. Propane holes are much smaller as it's higher pressure. More B.T.U.'s.

Cabin is located in south west Wisconsin an the Kickapoo river, on a south facing hill side, great view.

I don't like plywood either, so when it was time to frame up the bathroom, I used tongue and groove 8" carsiding, turned backwards, so as to match the walls, (looks like the flat side of the interior wall logs).

As you can imagine, mechanicals have proved to be challenging as there isn't hollow walls, except the bathroon wall, so that wall, studded in 6" studs for more room, contains then water piping, plumbing, venting etc.
There was a discussion on bathroom/kitcken sharing the common wall a while back. Anyway that is what it is.




Cabin is on sonit-tubes, and blocks, was built by the Amish and trucked in, sooo, according to local /Wi. codes, that makes it a "mobil home", alot of codes don't apply.
If I put it on a basement or solid footing they would apply.
You could cut off the porch, jack it up and head on down the road.



Soo, jury still out on the insulation issue, replacing the roof w/metal is a possibility, I guess asphalt shingles arn't a good choice for solar panels either, heat reasons.
At this time idea is,that the "Place" is  to be the north end of a "snow bird".
So there is some time to think this thru.

[keyholefarmhouse]

I can't imagine, with that beutiful ceiling, insulating it from the inside out.  Go without or put it on top.

Exposed plumbing or electric don't look so bad.  I like it.  The cabin looks great.  put it on the ground, pleez.

keyhole

[jraabe]

Those Amish cabins sure are nice looking. I didn't realize that they escaped local codes by being mobiles. It looks like the loft joists span the same direction as the rafters and thus do a pretty good job of tying the walls together. Most codes would allow 4' wide areas and probably up to 8' of unsupported wall length.

I'd be surprised if you actually experienced much bowing of the walls. The weight of the logs also helps somewhat I expect.

[hunter63]

John, It was an intresting wadding thru the in and outs of the "codes" and how you can get things done.
Example:
Because it is considered mobil, the elect needed a breaker at the pole matching the service size, but after it was inside, I could wire it up myself, have it inspected, O.K.'d then they turned me on.
Helps to have a couple of beers with the Co-oP guy on friday nite.

I did hang around (owned the land ) for 15 years before deciding to go ahead with the project, got to know a lot of local people, and there are ways of getting from here to there with out to much hassle.

Don't discuss much at that time (at the saloon), but just ask them to stop by, I need help with something.
The starting size, 16'wide by 30' long, 8' porch, installed @about 15k.

[glenn kangiser]

And Glenn, thanks for the pics, they are super but, dang I don't know how people live in that kind of cold! (I know, it's probably dry cold so it's like being on a beach!)
Okie Bob

All-right-- BoB ---
I should have known about the time I start giving people a bad time about their snow---we would get the biggest snow we've had in years.  Me and my big mouth. :-/  I had to plow over a mile of snow to be sure I could get to work Tuesday - I'm the only one on the road with big toys.  An icy or snowy road coming out of my place could very well mean going over the edge to the valley below-- the hard way.

Actually when the sun came out - even with the snow it got pretty hot, but when it went behind a cloud it got cold pretty fast.

[Amanda_931]

When John was mentioning spraying insulation like Icynene (or the soy-based version) directly to the roof sheathing, would that apply if I were using a rubber roof (paint on or glue on?) as well?

(I'm thinking that there might be a few fewer flashing problems with the rubber--not planning many, but the roof may be butterflied so the whole roof acts as a gutter for rainwater collection--going to an end much the same as the one in the house in Tasmania that Jonsey found)