Bulkhead relocation

[scotty]

I am considering moving the bulkheads separating the galley and head (not the main bulkhead under the mast) approx a metre aft to enable saloon type bunks fore and aft. Footwells or trotter boxes will provide extra room to stretch out. I will put the heads in the forepeak and the galley adjacent to the hatch steps.
My tophat is a shoal draft mark 3 with ply fitout which ive owned for 18yrs.
I will put "hanging knees" along the beam shelf between the bulkheads.
Has anyone done this before?

I have been told to leave alone or buy a new boat but i want to explore the possibility as i want to keep my toppy for as long as possible but with a more orgonomic arrangement. As my insurer wants a new survey soon i will also get his views as well

Regards to all

[steve]

Hi Scotty,
As long as the main bulkhead remains unaltered, as you propose, I don't think any other bulkheads are critical.
Certainly the cabin roof does not appear to need any support. Most Top Hats do not have any bulkheads (except the main bulkhead) rising to roof level. In the boats which have the heads aft of the main bulkhead, the wall which forms the aft end of the heads compartment is often not structural.
Some stiffening of the hull at low level is probably desirable. If you use a strong framework for the bunks and bond it securely to the hull, with mini bulkheads at each end of the bunks, I would think that would be sufficient even if you cut trotter boxes into these bulkheads.
Of course if you are planning to cross oceans you will need to get expert advice.
I sailed my Mark 3 for twenty years with no stiffening other than thin fibreglass tape bonding the fibreglass internal liner (which I understand you do not have) to the hull. The tape tore in a few places due to the hull flexing so I replaced it with much heavier tape and have had no in problems since.
Steve

[scotty]

Many thanks Steve - i certainly will not be crossing oceans so all good. Cheers

[Democritus]

I think I'd be asking a surveyor and architect rather than the forum. I'd also be checking with insurance company as any alteration without notification and agreement may void it.