Hull Interior Insulation

[FullCircle]

Would appreciate the thoughts on insulating the inside of my GRP hull in all the accessible areas. I am not going to strip it all out, so the job needs to be done in situ, and preferably without too much mess!
Would also appreciate any experience on the reduction of condensation with the use of insulation.

Thanks

 

[Krusty]

I did mine 18 years ago and it transformed the boat: dry, warm and quiet too. I used a 10mm flexible closed-cell foam (used at that time for lining military aircraft) supplied in 6ftx2ft panels by a firm called Functional Foam, in Wales. Unlike some foam-backed linings offered, it does not absorb any moisture, fastened easily with a range of adhesives, and has not deteriorated in any way. And it was surprisingly cheap. Try Google. Good luck.

 

[araucaria]

try to insulate with strips of real wood. It is higroscopic though expensive and difficult to work well

 

[aztec]

i'm using 25mm celotex, you can get it from builders suppliers. class 0 fire resisting, and good thermal barrier, i'm finishing over the top with carpet (in the bunks, and tongue and grooved pine on the extenal bulkheads.

 

[ShipsWoofy]

Did that add a lot of weight to the boat?


My ceilings have standard roof insulation packed in, the hulls have expanding foam behind plywood panels. Trouble with this method, to screw anything to the walls we have to dig out and glass in blocks of wood as the ply is very thin and you can not even screw a coat hook in properly. I guess anything else on a cat would be too heavy.

 

[nicko]

We used a poypropylene product (grey and white in colour) from our furnishing store - here in NZ. Our boating shops sell a similar product but it is more expensive.
It is quite easy to apply - just cut reasonably acurately to size (I used paper patterns first), spray with F2 glue or similar adhesive, and carefully apply. It is best to start in one corner and take care because it tends to stretch. Smooth off all over with the palm of your hand. it has worked well for us and stopped condensation as well as made the boat warmer.

 

[Krusty]

Re wight of 'Functional Foam' : this stuff is incredibly light (otherwise it would not have been used to line the skin of military aircraft). My order was delivered as a 16inch-high pack of 6ft x 2ft panels and weighed less than a 20litre can of fuel. My first reaction was horror at the loss of internal volume for storage, but when applied to the skin at only 10mm thickness there were no practical consequences. It cuts easily and cleanly with a craft knife: I used brown paper to make templates of the areas to be insulated, laid them on the foam and cut for a perfect fit: even in the back of small cave lockers. I have had visiting skippers comment 'just can't believe how dry this boat is'.

 

[Sans Bateau]

I can confirm that a boat with foam insulation is warmer and dry in winter plus stays cool in summer.

I hear some clever boat builders include it in their build process.