Insulation plan

[dprat1]

Greetings,
I will be insulating and setting the tub later today for my C-51. Was planning to glue some 1/2" pink foam board to the exterior of the tub and then use 3 1/2" unbacked fiberglass. Has anyone here done that before? Good idea....bad idea?
Thanks,
doug

[MCarter]

Dprat,

I used the foam board about 1" thick. Then DucK Tape the Seams them used 3" Insluation. Good Luck,

[BryanH]

I used backless R13 fiberglass (Seating the tub trick). Think it provides better coverage and fills the spaces easier than the board.

Having read this chain of posts and the posts linked to it about installing the tub.  Why remove the paper backing from the insulation?  And the cardboard shoehorns.  Why not plastic sheeting that is left in place as a vapor barrier

[BryanH]

That was my question also... was told it's more susceptible to mold & mildew.  Never thought about plastic sheeting, although with only metal surfaces maybe it isn't required??  I do know that the machines were originally made with fiberglass, no paper and no plastic.

[dprat1]

Interesting replies,, I was not able to find the time this weekend to install the tub as planned. The Mrs. had other plans and tasks for me this weekend. Actually, was not quite done getting things ready for winter and figured time was running out. Sounds like the weather is going to take a turn for the worse here later this week.
My plan to glue foam board to the exterior of the tub is with the intent to help keep the tub exterior from sweating or condensating. Kinda like wrapping a hot or cold water pipe to keep it from sweating. Then fill the rest of the interior cabinet with fiberglass insulation. With the foam board, I do not think it would matter if the fiberglass was paper backed or not. I do know that fiberglass insulation needs to breath and that compacting it will not only decrease its R value but also contribute to moisture retention. I think sealing with plastic would retain the moisture and lead to problems vs the foam board directly on the surface to insulate. Thinking realistically, this machine has survived quite well the past 50 years as it was. I can not say as much for my electric bill...so I think economy is more an issue that preservation. I don't think I will care about this when I'm 99 yeras old...god willing....right:) My bottom line......I think directly insulating the tub with foam board to keep the moisture in check from the fiberglass and then just enough fiberglass to fill the cabinet would be the most efficient. Hummm...getting long winded here.......sorry.
doug