Is the foam in corners above deck needed?

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Well-known member
Mar 28, 2022
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College Station, Texas
Hi, I am in the middle of replacing all the rotted wood in a 1987 16-foot MirroCraft Outfitter that I recently bought. Almost every piece of plywood was completely rotted. I have all new plywood treated with coats of diluted expoxy and wrapped in MariDek.

For simplicity I used all the old parts as templates and am keeping the original floor plan. It will be nice.

My question is, are the pour-in foam blocks that are above the deck and above waterline, necessary for stability or flotation?
There is a block of foam in each corner of the stern and one on each side of the livewell. Are these part of the safety design, or were they poured in just to fill empty space?

More details:

The bottom of the boat has a lot of foam in it below the deck. It's in good shape and I left it alone. There is foam all across the bottom for about 9.5 feet except for the middle channel for drainage to the bilge.

On either side of the livewell, which is in front of the steering console, there is a block of poured in foam. I can re-use them but am wondering if it is necessary to use them? These two spaces would make some nice additional hatches. The livewell is secured in place with plywood framing, all new.

In each corner of the stern, there also is a block of poured in foam. I can re-use these too, but I could also use the space for recessed rod holders and small hatches.

Can I delete the foam blocks or reduce them in size, or is it best to keep them?

Thanks much
The foam is only there to keep the boat from sinking with the payload that is on the sticker. If the mfg put it there, you would need it for it to have that same safety margin.
Thanks for the comments. i will keep all that foam as it was from the factory. The blocks in the stern would help float the motor. Those by the livewell would help float the bow if the livewell was swamped.

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