Increasing Bunk Size

[Boathook]

I'm going to increase the width of a single bunk to make it more comfortable plus getting a foam mattress, etc.
It presently has a GRP base.

I can either extend the width by laying ply over the existing GRP and extending to the desired width and building a light weight frame to support the extra width, etc. The other option is a heavier frame and butt the ply up to the GRP. The ply in both situations will be 'treated' and painted.

My main concern is laying the ply over the existing GRP base, will it get mould between the 2 materials. If it is likely to get mould will this be detrimental to health? Should I totally bed the ply down using an adhesive / sealant to remove any air gap and therefore stop any mould ?
If I just lay the ply down on the existing base it will have some screws to hold it in place and I might be able to make it removable though that is unlikely to happen ......

 

[dunedin]

In general the best thing for bunk bases is neither flat GRP nor plywood - but strips of material, which allows better ventilation.

Caravans moved to wooden strips, with tape to keep aligned, rather than ply wood at least 25 years ago. Boats have been much slower to make this simple change for the better.

 

[Refueler]

Can you hinge a flap side ? So bunk stays original until you want to sleep ... lift up flap ... drop legs down (maybe 1 each end and a middle one) ...

Similar idea to many tables on boats ... that way you still can move about when not sleeping etc.

 

[Daydream believer]

I would batten the GRP with 15mm wood strips. Then lay ply-possibly with 25 mm holes in it for ventilation drilled at a later date if desired. I expect that it will make a much drier base for the mattress. The battens need to be open to one edge to allow air to flow.

 

[Boathook]

Thanks all, so far. Boat was made around 1977 or possibly a few years earlier. Bunk is a permanent one and I am losing some 'hanging' locker space for this modification.
I have been using dry bed matting for the last few years and suspect that I will carry on but will look at slats as well, though the base is on a sealed area.

 

[Neeves]

In general the best thing for bunk bases is neither flat GRP nor plywood - but strips of material, which allows better ventilation.

Caravans moved to wooden strips, with tape to keep aligned, rather than ply wood at least 25 years ago. Boats have been much slower to make this simple change for the better.

Available from Ikea. We used them with total success on Josepheline, we bought curved ones (from IKEA) if you bought them oversized they would extend the bed base, width.

Jonathan

 

[Refueler]

Another idea >

Slide out extension base with legs ??

 

[Boathook]

Another idea >

Slide out extension base with legs ??

The bunk is permanent in its own cabin so once altered all I have lost is some hanging locker space. I'm also using the change to clear out some items that have been residing there for years !

 

[Mister E]

The slide out it slatted with its own supporting front.
The original base has slats that fill the gaps.