How much reflectix/rockwool did you use?

[RachBets]

We've decided on a single layer of reflectix followed by rockwool for our interior wall insulation in our 30' Argosy and are looking to gather some estimates. If you have used either, do you recall about how much you ended up using?

[TheGreatleys]

Sheesh, I wish I could remember this. Probably 5 packs of rockwool. We only did the top half in reflectix, so I don't know that my number would match yours, even if I could remember. We used double-stick foam tape to attach the reflectix loosely to the shell, so it would be able to fall away somewhat to take up any extra space in the assembly and add r-value. Used spray glue to stick the rockwool to the reflectix, which was really helpful for the upper sections. Cut 3-1/2" batts in half with a serrated insulation knife.

If you haven't already, I highly recommend adding a thermal break between your ribs and interior skin. We used foam tape and sill gasket, and we believe it's making a big difference.

[RachBets]

Originally Posted by TheGreatleys

Sheesh, I wish I could remember this. Probably 5 packs of rockwool. We only did the top half in reflectix, so I don't know that my number would match yours, even if I could remember. We used double-stick foam tape to attach the reflectix loosely to the shell, so it would be able to fall away somewhat to take up any extra space in the assembly and add r-value. Used spray glue to stick the rockwool to the reflectix, which was really helpful for the upper sections. Cut 3-1/2" batts in half with a serrated insulation knife.

If you haven't already, I highly recommend adding a thermal break between your ribs and interior skin. We used foam tape and sill gasket, and we believe it's making a big difference.

THANK YOU. We've been all over your blog and posts so so so appreciate the detailed explanations you have given. Our intuition was always rockwool but you certainly helped seal the deal. We spent at least two hours last night getting down to the nitty gritty of a thermal break. In a nutshell what we have gathered is that A. we're 100% going to seal the ribs in some fashion B. we really like your method but would like it to stick closer to 1/16 - 1/8 thickness to keep structural integrity and a greater chance of reusing the rivet holes. Leaning towards 1/16 single sided 3M vinyl foam tape, and going back through and punching through the tape or marking with a sharpie at the rivet holes.

[TheGreatleys]

Originally Posted by RachBets

THANK YOU. We've been all over your blog and posts so so so appreciate the detailed explanations you have given. Our intuition was always rockwool but you certainly helped seal the deal. We spent at least two hours last night getting down to the nitty gritty of a thermal break. In a nutshell what we have gathered is that A. we're 100% going to seal the ribs in some fashion B. we really like your method but would like it to stick closer to 1/16 - 1/8 thickness to keep structural integrity and a greater chance of reusing the rivet holes. Leaning towards 1/16 single sided 3M vinyl foam tape, and going back through and punching through the tape or marking with a sharpie at the rivet holes.

Glad to hear our blog is helping someone! When I was knee deep in renovation, I scoured as many resources as I could find. I got the foam tape idea from Reniergirl (on this forum) and she used thinner tape than we did. I think it'll make a big difference no matter how thick you choose.

[redthies]

We used a double thick layer of a reflectix type insulation. I looked at a ton of options and I found that there is similar R value between the product I used (it’s a double layer version) and the factory layer of pink. The lack of adding in mouse nesting material was a factor in my choice. Rock wool isn’t as bad as pink for being a habitat, but they will still prefer it to reflectix. I did the same insulation in a Wells Cargo trailer that I built for a client, and it’s unbelievable how well it holds the heat.
I also did a continuous layer with over laps to act as a vapour barrier and thermal break. It may have the added benefit of helping keep any future leaks from getting in to the interior.

[Big G]

Hi RachBets
I am getting ready to do the same thing to my 1974 Overlander. I plan on using two layers of reflectix above the window. The second layer will house the electrical wires. the first layer will be at the outer skin. the Rock-wool will be below the windows to meet the reflect. Was able to locate it in 48X24X 1-1/2 online from Loews. I also located 1-1/4 zip ties holder to replace the black clips that were installed in 74 from ebay