One major concern when converting a van into a livging / sleeping space, is ventilation. I did not want to end up with oxygen depleted air when keeping the windows shut due to rain or bugs.

A roof vent is ideal to solve these problems. I sucks the hot air out leaving you with a comfortable interior. My van came with a roof section designed to be cut out and have an air conditioning unit fitted which made it relatively easy to cut into the roof, fit the fan unit, and waterproof the whole assembly. Here is how I did it:


  • Reciprocating Saw
    included in my toolset
  • Sheet Metal Saw Blade
    included with reciprocating saw
  • Power Drill w/ various Bits



Step #1: Mark Vent Outlines For Cuts
Simply place the fan assembly onto the spot of your roof and mark the outline of it with a felt marker. This will allow you to make straight cuts that fit the fan perfectly and this will make it much easier to waterproof the roof in the later steps.

Step #2: Making the Cuts into Your Roof
This is the scary part. Before using the saw I used a power drill with a bit that had the same diameter as the saw blade in each corner of the felt lines from step #1. This allowed me to just make straight cuts without having to make turns which is pretty much impossible.

After you have cut out the area for your roof vent, you will most likely have to widen and / or clean up the cutting job. Take your time, the better the job is here, the it will hold up to rain.

Step #3: Place the Fan Unit, Drill Screw Holes, and Bolt it Down
At this point, the hardest part is done. Apply a generous ring of silicone sealant right near the edge of the cuts to create your first later of water proofing. Just place the fan assembly in its new space and drill the holes for the screws to attach it to the roof. Then set the bolts (nut towatds the interior of the van) and tighten them down.

Step #4: Water Proofing the Roof
This is a crucial step for obvious reasons. Use the automotive sealant (be extremely generous) to seal the outside lip of the fan assembly with the roof. Then the only weakpoint remaining are the screws, apply generous amounts of sealant to the screw heads and make sure it creates a solid bond with the metal of the fan assembly.

Tip: After all the silicone had hardened out, i removed the nuts of the mounting bolts from the inside of the van, applied silicone from the inside and tightened the bolts back down, creating an additonal layer of water protection.


All Done!
You are all set. Let the silicone harden and visually inspect for any gaps. Reapply if necessary. It is also worth using a gardenhose to check that everything is waterproof.

I have endured a few texas downpours with the van by now and I have not had any problems with leaking water or moisture in general. This is a great half day project that makes the van a much more enjoyable place to be.

Tweet about this on TwitterPin on PinterestShare on FacebookShare on TumblrShare on RedditShare on StumbleUponEmail this to someone