engine noise insulation

[Orcbait]

The engine room hatch cover on my boat (26 footer, twin 305s) has no insulation against noise, and I was thinking about adding some - not sure if people generally do this.

The hatch cover has a fiberglass strut running down the middle (underneath) for reinforcement, and this effective creates sort of two 'boxes' about 4'x5', say 4 inches deep.

Is there a preferred material for adding insulation here (for sound deadening) or is it even worth it?

Thanks.

Orcbait

 

[Bay2260]

Soundown makes the stuff. I think Boatfix carries it. It flat works!

Pete

 

[abdiver]

You can buy this really great sound deadening foam stuff. The really good stuff has a layer of lead (yes, lead) that is sandwiched between two layers of foam. It's expensive, I recall it being about $50 a square yard.

It is also heavy, which is something you might want to seriously consider before glueing it down on a hatch you have to manually lift.

If this hatch is over the engine then you want to make sure that the insulation is well secured to the hatch. I know of a large trawler style boat that had a chunk of the sound insulation fall off and lay across the top of the engine and eventually catch fire, destroying the boat.

Rod