Exterior floor slide out

Hello-I'm new to this so please forgive me if I don't put something where it belongs. My question pertains to the exterior floor of my slide outs. I noticed the other day that I had mushrooms growing along the bottom edge of one of my slide outs. Upon closer inspection, the underneath side of the floor is rather spongy right along the edge and actually, some of the screws that hold on the bottom most trim piece just pull out. When the slide goes in, they're so loose the rubber gaskets pull the screws out.
The inside floor along the wall appears to be intact so I assume there are actually two floors, one exterior and one interior (I don't know how it is constructed). Would it be possible to replace the exterior floor without disturbing the inner floor or are they one in the same. I would like to replace the exterior floor, put in new screws, caulk and see if that solves the problem. Would appreciate any assistance or advice Thank you

Hi GAWKN,

Welcome to the Heartland Owners Forum.

What trailer model, floorplan and year do you have? Which slideout?

danemayer said:

Hi GAWKN,

Welcome to the Heartland Owners Forum.

What trailer model, floorplan and year do you have? Which slideout?

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It is a 2009 Big Country by Heartland, 32.5. It Has 3 slideouts. Both of the large slideouts are about the same as far as the condition of the floor. It seems like if the piece of trim had been mounted just 1/4 or 1/8 of an inch lower then the ends of the
particle board/plywood would not have been exposed to moisture.
Thanks for your reply

I have seen posts in the past about 2009 and earlier builds where the edges of the slide flooring were exposed to the elements at front and rear of the slides. Heartland changed this either in late 2009 or 2010.

If the ends are delaminating, you may be able to stabilize the wood from further damage and install a protective cover.

danemayer said:

I have seen posts in the past about 2009 and earlier builds where the edges of the slide flooring were exposed to the elements at front and rear of the slides. Heartland changed this either in late 2009 or 2010.

If the ends are delaminating, you may be able to stabilize the wood from further damage and install a protective cover.

Click to expand...

Yes that is exactly what is happening, delaminating due to being exposed to moisture. I am considering placing some sort of larger piece of trim, possibly L shaped to try and cover the exposed ends.

Do you happen to know if the piece of plywood/particle board/subfloor you can see underneath the slide is the same as the interior floor? In other words, is there an exterior floor and an interior floor or are they one in the same. Is it just a single sheet of wood?

I think it's a single layer of wood.