How heavy should original foam be?

[speed_demon]

I pulled the floor in my 1998 Woodlridge 17ft Alaskan and the foam didn't seem to be waterlogged but it's definitely heavier than the purple closed cell foam you can buy at the hardware store. I called Wooldridge and they said the coast guard requires them to use a very expensive high grade foam and it is up to 10 times heavier. They quoted me $600 and they are usually very reasonable on prices.

I just want to know if this is true or not because if not I'll go with something lighter.

 

[Chris1956]

Re: How heavy should original foam be?

I have never heard of that. Look at Westmarine website. Look for twopart pourable foam. Foam has a weight/density specification. See how that compares with what you have. Also, if you can squeeze your foam and no water comes out, it is probably OK.

 

[ezmobee]

Re: How heavy should original foam be?

Most of the restore guys here are getting their pourable from here: Urethane Foam , Expanding Marine Polyurethane Foam (U.S. Composites. Their web site is horrible but their products and service are good).

 

[ondarvr]

Re: How heavy should original foam be?

The foam does cost more, but the density (weight) is low, about 2lb per square foot. Some builders use foams that are slightly lower in weight.

I have freinds that work at Wooldridge and I'm not aware of them using a foam with a density 10x heavier.

It also depends on exactly what he was compairing it to, if he was comparing it to 1/2 lb foam then it could be 5 lb and be 10X heavier, but with the normal 2 lb foam they would need to use 20 lb foam, which would weigh a great deal and cost a fortune.

 

[jigngrub]

Re: How heavy should original foam be?

USCG compliant expanding urethane foam is 2lb. density, it weighs 2lbs. per cubic foot.

Foams with a density of less than 2lbs. absorb water quicker, foams with a greater density are more water resitant and weigh more.

4lb. density is used in some boat that need extra structural support, but 2 lb. density is the more common foam in the majority.

Here's a page about floatation materials from the USCG website:
Flotation - Flotation Materials

 

[speed_demon]

Re: How heavy should original foam be?

I compared the special floor foam against the side flotation styrofoam and it was actually about 4 times heavier. I must have mis-quoted wooldridge. They said it was special because it was flame retardant and will never take on water. I balanced a few of the pieces and they don't seem to have any heavy spots.

 

[speed_demon]

Re: How heavy should original foam be?

Here's a page about floatation materials from the USCG website:
Flotation - Flotation Materials

It looks like manufacturers do have to use high grade foam. I doubt the pink stuff from Lowe's would survive the USCG requirements.

FEDERAL LAW

183.114 Test of flotation materials.

(a) Vapor test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed in a fully saturated gasoline vapor atmosphere for 30 days at a minimum temperature of 38 deg. C.

(b) 24-hour gasoline test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed for 24 hours at 23 plus or minus 2 deg.C in reference fuel B, of ASTM D 471 (incorporated by reference, see Sec. 183.5).

(c) 30-day gasoline test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed for 30 days at 23 plus or minus 2 deg.C in reference fuel B, of ASTM D 471 (incorporated by reference, see Sec. 183.5).

(d) 24-hour oil test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed for 24 hours at 23 plus or minus 2 deg.C in reference oil No. 2, of ASTM D 471 (incorporated by reference, see Sec. 183.5).

(e) 30-day oil test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed for 30 days at 23 plus or minus 2 deg.C in reference oil No. 2, of ASTM D 471 (incorporated by reference, see Sec. 183.5).

(f) 24-hour bilge cleaner test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed for 24 hours at 23 plus or minus 2 deg.C in a 5-percent solution of trisodium phosphate in water.

(g) 30-day bilge cleaner test. The flotation material must not reduce in buoyant force more than 5 percent after being immersed for 30 days at 23 plus or minus 2 deg.C in a 5-percent solution of trisodium phosphate in water.

(h) The buoyant force reduction in paragraphs (a) through (g) of this section is measured in accordance with ASTM D 2842 (incorporated by reference, see Sec. 183.5).

 

[metriccrescentwrench]

Re: How heavy should original foam be?

I doubt the pink stuff from Lowe's would survive the USCG requirements.

It wouldn't even come close. It would more than likely dissolve in gasoline (much less not losing buoyancy after being immersed for gas for 30 days).

 

[H20Rat]

Re: How heavy should original foam be?

It wouldn't even come close. It would more than likely dissolve in gasoline (much less not losing buoyancy after being immersed for gas for 30 days).

10-4. pink foam dissolves into a gooey mess when it touches gasoline. I have built quite a few speaker boxes by gluing together layers of pink foam, shaping, fiberglassing over them, and then dumping in some gasoline. Come back later and dump out the foam!

One thing to note.. (and although i don't condone it in any way) The USCG specs explicity apply to OEM manufacturers. An owner working on a non-commercial private boat does not need to meet USCG requirements in any modifications. Again, putting USABLE foam back in is absolutely a good idea, putting pink foam in would be a horrible idea,, as well as not putting any foam in.