Good ventilation is one of the most important (and most overlooked) parts of any van conversion.
It keeps the air fresh, reduces condensation, and makes the interior far more comfortable to live in.
This guide explains why ventilation matters, the different types of vents you can install, and how to choose the right setup for your build.
👉 Browse our full range of roof vents, skylights and fans:
https://highpeakconversions.co.uk/category/exterior/roof-vents/
A campervan is a sealed metal box – without proper airflow you will quickly run into problems:
Breathing, cooking, and even sleeping releases litres of moisture into the air.
Without ventilation, this moisture condenses on cold metal, leading to:
Damp bedding
Mould
Rust behind wall panels
Good airflow keeps the van from feeling stuffy, particularly in warm weather.
Fans and skylights help move hot air out of the roof where it naturally rises.
Ventilation is essential when using:
Diesel heaters
Gas cookers
12V fridges
Fresh air prevents fumes and stale air build-up.
There are three main methods used in van conversions:
This includes:
Roof mushroom vents
Simple skylights without fans
Floor vents for heaters or gas appliances
Pros:
Silent
No power draw
Always providing a small amount of natural airflow
Cons:
Not enough on their own for cooking or hot weather
The most effective option — especially in summer.
Typical 12V roof fans include:
Maxxair-style fans
Fiamma Turbo Vent
Dometic fans
Slimline extraction fans
Benefits:
Pull stale air OUT
Draw fresh air IN
Great for cooking areas
Keep the van cooler at night
Top tip:
Pair a fan with an open skylight for a cross-breeze.
Adding natural light and airflow, these are great for:
Sleeping areas
Shower rooms
General ceiling ventilation
They’re also ideal if you don’t want a noisy fan above the bed.
👉 Browse our skylights & vents:
https://highpeakconversions.co.uk/category/exterior/roof-vents/
Correct placement makes a huge difference.
Works best for:
Cooking
Night-time cooling
Drawing airflow along the length of the van
Provides natural light and gentle airflow while sleeping.
Reduces condensation and steam.
Ensures proper combustion air supply.
A simple rule for most conversions:
1 roof vent OR 1 powered roof fan
1 powered roof fan, plus…
1 skylight or passive vent for cross-flow
2–3 vents spaced along the roof give the best balance.
Most 12V roof fans draw:
0.3–1 A on low
1–2.5 A on medium
3–4.5 A on high
This is very efficient and easy to supply with standard van wiring.
Recommended cable:
1.5 mm² for most fans
2 mm² if wiring run exceeds ~5 metres
Fuse:
Typically 5 A or 10 A depending on the model
Even with insulation, vans still produce moisture.
So combine:
This combination keeps the van dry, protects the metalwork, and prevents damp bedding and mould.
Installing a vent sounds scary, but it’s straightforward if done carefully:
Measure twice, cut once
Use the vent’s template
Deburr the cut edge
Paint the raw metal with primer
Use the correct mastic/sealant
Secure evenly without over-tightening screws
Most installers do this entire job in about an hour.
Yes — common layouts include:
Vent at the rear, panels at the front
Panels either side of a central roof fan
Slim skylights placed between solar rails
Just ensure:
The vent can fully open
Airflow is not obstructed
Cables and mounts are not in the cut area
We supply a range of:
👉 Browse the full collection:
https://highpeakconversions.co.uk/category/exterior/roof-vents/
Good ventilation is essential for:
Reducing condensation
Keeping the van comfortable
Improving air quality
Staying safe
Making the interior feel fresh year-round
The ideal setup for most vans:
➡️ 1 powered roof fan + 1 skylight or passive vent
This combination gives excellent airflow with low noise and minimal power draw.
