Insulating an Old Cabin
LESLIE: Mike in North Dakota is on the line with an insulation question. How can we help you?
MIKE: So, we’ve got a – I recently purchased, last fall – living in a very cold environment up here in northern – North Dakota – a cabin of which – the trunk of it was built in 1940. It’s quite old. Some of it was recently updated but the cabin itself is never, I guess, built or updated to be a four-season building. So, in the wintertime, they had an external pump that provided water to the place. They would close all the water off, drain the pipes off with an air compressor and basically close it off.
Well, we are ultimately going to retire to that and add on to the cabin that stands today. But I’ve now got this problem of trying to figure out how to insulate from the floor up. And it’s nothing but 2x4s and plywood that keeps us between a little bit of carpet and frozen tundra. So I’ve got to figure out how to insulate this entire thing so that water pipes, toilets work, all of these other things all year round versus just in July up here.
TOM: Are the walls exposed?
MIKE: The walls are not exposed, I guess, if I’m understanding what you mean by that. There is insulation in the walls themselves. It’s not real thick but a pellet stove is sufficient to heat this small place warm. The rest of it is, I think, just blown insulation that was done well after the fact, into the ceiling. But there is nothing at the floor and a crawlspace under the cabin is only about a foot-and-a-half or so worth of thickness. It’s pretty hard to get under there. It’s just a 2×6 or 2x4s of plywood – ½-inch plywood.
TOM: OK. So, what about the attic? Is that – like can you see the underside of the rafters?
MIKE: Can’t. Can’t get in there at all.
TOM: Yeah. You’d probably have to cut an opening to get in there.
MIKE: Yes. That’s exactly what we’re looking at. At best, I can see in there through an outlet that I could remove.
TOM: OK. So given your location in North Dakota and the limited amount of space you have to work with because you have smaller structural members – you mentioned 2×6 floor joists and that sort of thing – what I would think about doing, if I possibly could afford it, was to use spray-foam insulation.
If you use spray-foam insulation, you’re going to end up having expose those walls. It might involve you removing drywall and that sort of thing to get to this. But it would be well worth it because you can get a higher R-value per inch with spray foam that you could with fiberglass.
Just as important, when you use spray foam, you not only insulate but you weatherproof, as well, because it seals out drafts which, of course, you get a lot of. If that was the case, you could spray-foam the walls, spray-foam the underside of the rafters and potentially, depending on the access issue, which you mentioned, spray-foam in between the floor joist into the crawl space.
The difference in that cabin will be nothing short of dramatic, because it’s just so darn effective when you use foam insulation.
MIKE: Interesting. And this – so this would be done, I would assume, after. Because I’ve got to have a brand-new well drilled, as well, about 50 feet down into fresh water. And that, I think, tunnels underneath the existing structure. So after we get that done, I’m assuming, is when we would do all the spraying to account for bringing the well in.
TOM: I would think so. You would want all your plumbing done before – and your electrical done. You know, we did spray foam in our home, which is over 100 years old, this past year and before we actually had the – Icynene come in and do it, I actually took time to sort of tidy up all of the wiring and run any plumbing I had to run and just kind of did sort of maintenance things. Because I knew that once they put the foam in, I would have to deal with cutting that foam out if I needed to do anything over and above that.
So, yeah, you’re going to want to do any of that updating before you have the foam sprayed. But look, if you’re going to open the walls up to do this, there’s never an easier time to do all that work than right then and there.
MIKE: Right, right. OK. Well, great. I absolutely appreciate the input. This is going to turn into, I think, a [fairly good science project] (ph) but I needed a good starting place, so I appreciate your help.
TOM: You’re welcome, Mike. Good luck with that project. Thanks so much for calling us at 888-MONEY-PIT.
LESLIE: Well, thank you so much for calling The Money Pit.