Expanding foam insulation

[lumphammer]

There are some bits of hull that are not accessible for installing insulation sheets, but would allow the nozzle of a tube of expanding foam to fill in the space.

I believe the standard foam types are not closed cell and would absorb water over time.

Is there a preferred type? I think I read somewhere that the fire resistant foams are closed cell is this right?

Thoughts or suggestions gratefully received.

 

[Kelpie]

I thought polyurethane foam was always closed cell?
One tip, if doing more than one can's worth, or if you prefer an easy life, go and buy a foam application gun (£7 off eBay) and use gun grade foam. You get much, much better control over the rate of discharge, and you can simply put thr can down part used and come back six weeks later and pick it up and start again. So much better in every way than the one-shot cans.
Also, consider using low-expansion foam if spraying into a confined space. It still expands by the same amount, but does so instantly, so you know when to stop. The normal stuff keeps on expanding for about an hour and can cause damage through overpressure if used in a confined space.

 

[Fr J Hackett]

If you do it make sure you have weep holes to allow for the expanding foam to escape otherwise you could find it deforming or worse sections of the hull and fittings. Doing it in several applications is not a bad idea.

They are available: http://www.shopmaninc.com/foam.html

 

[vyv_cox]

Builder's foam is fine provided it is not used in areas that are permanently wet or immersed. I injected some around my cool box years ago and it is still intact and dry.

 

[waynes world]

Poly foam is closed cell, well i bloody hope so ol.

this i show i insulated mine while go. I used as said above, a gun kit and cleaner for later use, weap holes so not to blow out any panels

Dont be afriad if you need to drill plenty of weap holes, easy enough to fill over