Best Installation Sealant for Ventline Roof Vent VP-543SP for Most Water-Resistant Performance

Question:

How waterproof is this vent when installed.

asked by: Gary T

Helpful Expert Reply:

The degree of protection from moisture when installing the Ventline Vanair Roof Vent with 12V Fan # VP-543SP will really depend on making seamless contact between the vent's mounting surface and the surfaces on the Transit Connect.

The best install comes from using a flexible pure silicone caulk adhesive, such as white caulk # 0160297. Most hardware stores will offer a pure silicone caulk like this in a range of colors, even clear, so you may be able to source some locally that better matches or compliments the vehicle color. This is good to keep in mind since this product cannot be painted.

I recommend multiple applications, both on the interior and exterior side of the mounting surface. The silicone is the best product because it remains flexible even a very low temperatures and is quite durable. Silicone also provides excellent grip between the vent's plastic and the vehicle's sheet metal exterior. This product takes a while to fully cure, usually around 24-hours, but it will set up after a few hours.

This vent is not labelled by Ventline as "water-proof" since heavy rains and high winds together can sometimes get water in places you'd never expect it to reach.

expert reply by: Adam R