Campervan Conversion - Part 2 - Stripping out, Rooflights and Partial Framing

Since the first post, I've been clearing out the van load space.  I'd originally thought of keeping some of the previous panelling but after I'd seen how the battens were fixed I decided to change the whole framing arrangement to provide additional support in some areas to suit my design.

It was quite a task and took several days to demolish the existing panelling and fitments to bring the vehicle load space almost back to the condition it was in when it left the factory.  Many of the panel and flooring screw heads snapped off when I tried to remove them so there was a lot of cursing and a fair amount of drilling & grinding required.

I didn't remove the floor panels at the front of the load space - there is a solid aluminium plate over this location covered with a rubber matting.  At the rear however, there was a thick plywood base which I stripped out to expose the steel floor of the van body.  

steel floor exposed at the rear

After cleaning, I re-used the two large formica panels I'd removed from the walls, marking & cutting them around the wheel arches to form a new floor in the rear section.   Before laying these formica sheets, I applied some beads of mastik on top of the van floor ribs to create a softer joint in an attempt to reduce noise from vibration, and then screwed them down using stainless self tappers.

formica rear floor panelling

So now we have a level floor area across the whole load space.  I've left the rubber matting on the aluminium front section for now, since it's more comfortable to kneel on during the build works.

'bare' vehicle ready for framing

Onto the framing, I'd bought 30 lengths of 18x44 mm planed softwood timbers.   I used some of these to make horizontals to fix along the whole length of the load space, so there are now five such rails along each side.   I used self-drilling wing screws to secure the wood to the van's reinforcing members.

At this stage I didn't add any similar rails at the roofline, because I haven't yet finished the design of the ceiling and its supports.

I then turned to fitting rooflights / vents towards the rear of the van, to provide some natural light in the darkest recesses of the space.  I bought two identical units from Fiamma, which require 280mm square holes to be cut in the roof.  These are designed to provide a degree of constant ventilation even when fully closed, and can be manually opened to allow more air flow as required.   There's also a removable aluminium fine screen fitted on the inside to stop any insects getting in.

On the LH side of the roof, there was already a smaller rotating vent fitted, so I removed this assembly and positioned the new square hole so it included the round hole for this existing vent.

I marked the van roof from the inside.  The internal parts of the rooflights are larger than the cut holes, so it's important there's enough space provided around the holes so the internals don't foul the roof crossmembers.   

I then drilled through the van roof at the corners of the marked square holes, from inside.   With the cordless jigsaw, I climbed on the roof and cut the square holes, dressing the edges afterwards with a grinder and file.

also shows the upper timber framing rails on the side walls ...

The rooflight on the LH side of the van, i.e. as shown on the right of the picture above, will be situated above the rear of the kitchen space (if we stick with our current design).  The vent on the RH side of the van will be wholly enclosed within the new shower / toilet room.

I used a cold galvanising treatment around the cut edges of the steel van roof.  I've used this Zinga before, it's very expensive but a little goes a long way and it has an infinite shelf life, being simply a suspension of very fine pure zinc particles.

square cut-outs in the roof ...

It can be seen that the cut-outs cross several longitudinal stiffening ribs on the van roof, yet the rooflight requires a flat surface to sit on.  I used a 2.5 mm thick,19 mm wide caravan mastic strip around the edges of the holes, building it up in layers to eventually produce a flat landing area at the level of the highest protruding rib.   I then applied a hydrid sealing / bonding compound around the underside of the rooflight external frame, and positioned the frame in the hole.

I'd previously made up a couple of simple square timber frames for the insides of the holes.  The rooflight is secured by clamping it using screws through its internal frame, forming a sandwich with the roof metal as the filling.  Tightening the screws pulls our timber frame up against the roof, trapping it and also compressing the mastic strips above.

from inside, flyscreen not fitted yet ...

Afterwards, I climbed on the roof again and cut away the excess mastic with a sharp knife while it was still soft and pliable.   The next day, I used the same sealing / bonding compound to form a bead all around each rooflight at its contact with the roof.

sealed for life, hopefully ...

So that's the progress to date.  The next post will likely be about fitting acoustic and thermal insulation.