Rotted floor and stress cracks question!

[Mjust]

I have a 1996 thompson calae 1800 which is an i/o open bow boat. I noticed that i had a soft spot on both sides of the floor that runs along side the motor /bilge area. These two sections of floor are 24" wide and 35" deep back to the transom. I can tell the original owner replaced the floor from the front of the boat all the way back to where the motor starts but didnt do along both sides of the motor back to the transom. I pulled up a section of the floor that was soft and found that there seems to be two stringers running about 8" apart from each other and filled with foam between them. The stringer closest to the bilge area was only covered with fiberglass from the transom forward for about two feet the the top was exposed wood that has some wet rot in it. The other stringer running closer to the side of the boat is fully wrapped in fiberglass and looks really good. I had a local shop come out to give me a quote to replace the two sections of floor and glass over the new wood. The gave me a quote of $750 dollars which to me seems kinda high for half a sheet of marine plywood, some screws and glass. He told me about 3.5 hours of labor per side due to the fact that the have to grind the old wood out along the transom and side of the boat. Does this price seem right? It doesn't look like much to me. The other thing he told me is that due to the one stringer having some rot that it would be an additional $3000 to gut the boat and replace the stringers. I have read online that you can scrape out the rotted wood since were only talking a small amount and fill with a resin. He showed me some stress cracks on the bottom of my boat on both sides of the very bottom V portion of the boat which would be under the motor. I took some pics, hard to make out but im looking for an opinion on what you all think.

 

[Solittle]

Re: Rotted floor and stress cracks question!

$750.00 seems extremely reasonable if he replaces all the rotten wood. Have you checked the transom?

The thumbnails are not the best images but the cracks look more like gel coat stress cracks than true structural cracks. It is hard to tell from those photos.

 

[Big Keepers]

Re: Rotted floor and stress cracks question!

Marine plywood averages about $100 per sheet. The $750 dollar price is pretty reasonable. I've done stringer and floor repairs before on boats my friend owned. As far as stringers are concerned, a lot of the time you can just double up the stringer without chopping up half the boat and pulling out all the dead wood. It depends on how bad the wood is rotted and soaked. First and foremost is getting the underneath dried out. When we replaced the floor on his old 20' Marlin we tore up the plywood as carefully as possible to use as templates for the new floors. Then we let it dry out for a few days. It was mid July so there was little rain and plenty of sun.

His stringers were soft and a bit rotten but not totally destroyed. We were able to run new stringers along the dead ones and screw right into good wood. Then we glassed them to keep them water resistant. Mainly the sides and edges along the floor. The top got some glass but not as much as the rest.

The floors were cut to fit and then installed. The edges were glassed to prevent water from running down the sides and under the floors. The top if wet can dry if left open to the sun. The finishing touch was some low knap outdoor carpet.