Floor Soft Spot

[Chopper]

Hi all,
I've just noticed what seems to be a slight soft area in the middle of the floor area (drivers side beside motor box) At the moment it is only a small area, but obviously it will get worse if not fixed.

I assume the only way to fix it is to remove the carpet and remove / replace the effected area.?

Has anyone else experienced this problem.? Is there likely to be many other hidden nastys waiting for me when I do this.?

Has anyone experienced anything like this.? Is it an involved / expensive fix.?

[bkhallpass]

RE: Floor Soft Spot

Hey chopper, what year and type of boat. It makes a difference
in terms of what materials were used, etc.

BKH

[OldFart]

RE: Floor Soft Spot

sometimes u can peel the carpet back, get it started & use a putty knife for example. NOT sure if a SLIGHT amount of a chemical is required. If so, be sure it isn't gas or something that will ruin the backing material.

[Chopper]

RE: Floor Soft Spot

Sorry guys,
98 Ski. As I understand, they are full composite construction, so I'm assuming it's early stages of glass "dry rot".?

I have already replaced the rear centre floor as it was bad. Carpet came off that no problems.

[M3Fan]

RE: Floor Soft Spot

How is this possible with no wood??? Never heard of it, somebody educate me already...

[DavidF]

RE: Floor Soft Spot

There is no such thing as "glass dry rot", unless the fiberglass is subjected to direct sunlight for an extended period of time. What has probably happened is failure due to a high impact load or repeated flexing due to stepping into the boat in the same place many times over the years.

Basically, the fiberglass composite floors of all modern CC's are supported by structural foam. The floors are no more than 1/4" thick and generally less to about 1/8" thick. So, high impact or point loads can flex the fiberglass and actually compress or crush the structural foam. once the foam is compressed, it does not spring back with the fiberglass and you end up with a void that you can feel flex under your weight. Over time, the repeated flexing MIGHT cause the fiberglass to develope stress cracks that can let in water.

One solution: peel back carpet to expose soft spot. Using a wood (paddle) bit, drill a 3/4" hole or so through the fiberglass floor. Mix up some epoxy resin and poor into the hole to fill the void between floor and foam. Using fiberglass cloth AND matt (alternating) with epoxy resin, patch the hole. Sand smooth and glue carpet back down. Avoid high point loading in the future. I.e. do not jump into the boat, but rather step in.

This is my $.02, your mileage may vary.

[bkhallpass]

RE: Floor Soft Spot

Yep, David F knows his stuff here. He's rebuilt a couple from the ground up and
generally knows how these things are put together. I would encourage you to consider
his advise.

BKH

[Chopper]

RE: Floor Soft Spot

Thanks DavidF,

It's only very small at the moment, but I might peel back the carpet to investigate further after summer. I haven't owned it since new, so I can't really comment on it's history, but we don't get in the boat from this side, usually only from the boarding platform.

I do put my fat sacs in this general area though. Maybe this is contributing to the problem, but I wouldn't describe it as a high impact load, more of a distributed load. Maybe I should construct enclosures for the sacks to distribute the load mere evenly.

[EarlyRiser]

RE: Floor Soft Spot

It's not as good as DavidF's advice, but it depends how much $$ u want to put into the job. U can drill the hole, or a couple to ventilate & dry any "condensation", then buy some spray foam w/ the small (easy to lose straw nozzle, see wd40), & spray into the hole until it expands out the other hole(that is close by). I doubt the concern is a large area, so this would be NOT effect floatation, structure, etc... My $.01 ER