When I rebuilt my Seaforth I used leather cloth glued to cut and shaped quarter inch ply. If there is nowhere to screw it to under the deck head, then bond some laths in using either GRP matting or CT1 glue. Once these are dried you can screw the panels to them using coloured cup screws of thin hardwood batons. See picture.

When I restored my Seaforth the headlining was in such a state that I threw it out. The relatively large sheets of damp ply covered in vinyl were beyond recovery. They were also quite large sheets that I thought would be a pain to copy.  Instead of ply which would be prone to damp I decided to go the Upvc route.  I had used cladding before at home and thought it worth a try. In order to leave space between the cladding panels and the grp I glassed in some foam stringers . Over these I then added some pvc trim strips which further increased the space between.  This also allowed me to use heavy duty stick on velcro to secure the pvc cladding to the pvc strips as the surface of the glass stringer would be an uneven and unsuitable surface for velcro to adhere to.  I secured the pvc trim strips with a small number of stainless screws which went through the stringers and marginally into the above grp.  Since the deck on my Seaforth is a double skinned grp sandwich there was no worry about damaging the watertight deck as it would only be in the lower layer.( I don’t know if yours is double skinned so you need to check it first before using any screws) . I strategically placed some velcro on the strips and likewise on the cladding panels to meet up. The cladding panels were 250 cm wide and 2.6 M long. If  I remember it took eight panels to complete. It was easy to fit one at a time and they are very light. They are also easy to cut to size.

I have had no problem with condensation as there is approximately just under an inch of space underneath and the panels are hollow and provide a thermal barrier . It was also easy to cut out for lights and things and the space is perfect for wiring and cables. You could if you wanted fit insulation in between but I have found there is no need.

I am really pleased with it and it is so easy to clean and remove a panel if you need to. One thing I would say is don’t use too much velcro as I did to begin with as the cladding becomes more difficult to remove. Just enough to hold the panel is sufficient.

I have enclosed a photo that shows the work as it progressed. Its been great for several years now and still looks good. When I have needed to do some wiring it has proved a doddle to take a panel down and then push it back in place .

McWester Mk 3 Ketch that requires a head line face lift . ( along with several other jobs). Peter Lloyd your job with the soffit board and pvc trim looks great. Was the self adhesive velco strip to the PVC trim and back of PVC soffit board ? Thanks and great to find this forum.

Hi Peter/Pat

The cladding is reasonably flexible but not for small sharp curves. In the saloon it is no problem as it runs the length of it. Across the cabin as each panel is approx 10 inches wide  it follows the curve naturally. In the forecabin where the headroom drops to deck level I used foam backed white vinyl and then cladding on the level bits up to the vinyl edge to which I fixed some trim. I have a photo where you can see the cladding facing up to the vinyl. It hadn’t been finished or trimmed in the photo but it gives an idea as to how it was done.

In reply to your query Pat I fixed the velcro to the facing surface of the PVC trim  attached to the stringers . The other velcr under the cladding panels and pushed them together.  I overdid the velcro so use trial amounts for the correct adhesion so its easily removable if needed.

Hope you solve the keel issue Peter.