Expanding foam use

[brightspark]

Bit like the concrete lorry driver that spotted his wife's boyfriends car parked with the sunshine roof open some years ago ........... Several tons of concrete later ......

they wont deliver or tip on anyone's drive now unless the buyer is there because of that

 

[500e]

Was not worried about shell life the owner totaled 5 shells in one season, we had a standing order with the Roots dealer

 

[Gwil]

I am a boatbuilder & have seen foam used in boats for many years. Regardless of if its single or two pack it will absorb water sooner rather than later & will cause a hall of horrors if used anywhere damp. No way would i use any of it below the waterline.
I would not use it in any steel section as single pack is moisture curing anyway & condensation will cause rust.

Absolutely right, I'm a retired marine surveyor, no repeat no foam, single or 2 pack is 100% closed cell. Also under vibration/structural movement it loses adhesion with the external skins. Moisture gets in the interface and completes the Little Ship of Horrors. Fine for short life structures, not for the remotely long haul.

 

[Member 66061]

Absolutely right, I'm a retired marine surveyor, no repeat no foam, single or 2 pack is 100% closed cell. Also under vibration/structural movement it loses adhesion with the external skins. Moisture gets in the interface and completes the Little Ship of Horrors. Fine for short life structures, not for the remotely long haul.

But what about Etap yachts?

 

[Gwil]

But what about Etap yachts?

They won't sink....but neither will a polystyrene fish box!

Seriously though, I haven't found core separation on ETAPs I've surveyed. But, I have found elevated moisture levels around fittings, in some areas obviously this area is saturated. This is both around original fittings and badly fitted additions.

It's very common in foam cored decks, and if allowed to freeze structural security is lost, the foam turns to a squidgy mush and you can bounce up and down on the deck. I've surveyed boats with core separation in large areas of the hull. Only advice to potential owners is to walk away.

 

[Shox Dr]

Havent people used it to destroy speed cameras?

Its definitely not hair mousse....

I don't know why whenever I see this picture, I hear a Scotish Accent. (...and just out of picture a tin of Striker)

 

[Member 66061]

They won't sink....but neither will a polystyrene fish box!

Seriously though, I haven't found core separation on ETAPs I've surveyed. But, I have found elevated moisture levels around fittings, in some areas obviously this area is saturated. This is both around original fittings and badly fitted additions.

It's very common in foam cored decks, and if allowed to freeze structural security is lost, the foam turns to a squidgy mush and you can bounce up and down on the deck. I've surveyed boats with core separation in large areas of the hull. Only advice to potential owners is to walk away.

I find your replies interesting. Sorry to bring the thread off topic, but now ive got to know how do you insulate a boat? How do you keep the heat in the boats where the cabins are below deck?

 

[ajlelectronics]

Jaguar used foam in their sills for a time, with the previously described consequences.

 

[Gwil]

I find your replies interesting. Sorry to bring the thread off topic, but now ive got to know how do you insulate a boat? How do you keep the heat in the boats where the cabins are below deck?

Well, a good question! Most boats these days will have foam cored decks, and boats built in Europe and the far East will have cored topsides. US construction is, in the higher price ranges, more conservative, and until recently was much more likely to be solid laminate.

Cored decks and hulls form effective insulation, otherwise infills of fire retardant polystyrene, or in the case of steel or aluminium boats foam spraying of the hull before fitting out, are effective alternatives.

Lots of production boats were under insulated in the past, and mouldy lockers and deckheads came as standard....

 

[500e]

our Dufor had a balsa layer in deck & it did delaminate nightmare time

 

[Bullet2012]

Just had the workshop roof spray foamed