A Complete Guide to Camper Van Roof Vents (2025)
- Shane Monks O'Byrne
- May 7, 2022
- 18 min read
Updated: 3d
A camper roof vent is a must if you're to enjoy your experience on the road. In summer, a campervan is a hot metal box. Without the airflow provided by proper venting, this quickly becomes unbearable. Even worse, poor air circulation leads to very bad indoor air quality due to cooking, moisture, and smelly clothes. Smells and moisture infest clothes and bedding, giving an overall air of mustiness. Moisture buildup indoors also produces mold, which ruins your woodwork and insulation. A roof vent effectively keeps your van cool, fresh, and moisture-free. In our Roaming Home study, we found that 52% of vans had a fan installed. In this guide we will discuss campervan fans, skylights, and air conditioning. We'll go over pros and cons and detail the installation process for each.
If you want an updated, detailed step-by-step installation guide for roof vents, check out our new article on the excellent Dometic Mini Heki unpowered roof vent.
Index
Shane, the founder of The Van Conversion, is a campervan professional and NCC-certified electrical installer. Since 2020, he’s lived on the road full-time, completing several van builds along the way. He’s the author of Roaming Home and the creator of The Van Conversion Course, which have helped thousands build their own vans. Shane also writes The Van Conversion Newsletter, where he shares hands-on tips and practical insights. He’s passionate about empowering others to make their vanlife dreams reality.
This post contains affiliate links, which means that if you click a product link and buy anything from the merchant (Amazon, eBay, etc.) we will receive a commission fee. The price you pay remains the same, affiliate link or not. By using these links, you are helping us to continue writing free educational content. To understand our policies on content, affiliate commissions, and liability, please review our Terms of Use.
Did you know you can get a free electrical wiring diagram by signing up for The Van Conversion Newsletter?
Supplies List
This is a sample list of supplies for installing your chosen roof vent. Besides the vent itself, you'll need:
 | A power drill of at least 500W For driving and drilling |
 | HSS drill bits For drilling through your van's metal panels |
 | For protecting bare metal from rust |
 | For filing burrs on exposed metal |
 | |
 | Tapping and cutting fluid To safely lubricate the metal as you're cutting it with the saw |
 | Sandpaper For finalising cut edges after deburring them with a file |
 | Your preferred flexible silicone-based sealant For sticking and sealing the vent to the roof Read more about sealants in our comprehensive guide |
 | A selection of clamps |
 | Timber To build your interior frame |
 | To form a level and watertight surface which the vent mounts to Read more about sealants in our comprehensive guide |
 | To bind your interior frame together |
What is the Best Camper Van Roof Vent?
The two most popular brands of campervan fan are Maxxair and Fantastic. I personally have a Maxxair Maxxfan Deluxe and absolutely love it for the following reasons:
It has a built-in rain shield, making it great for all weather conditions. This is a super important feature, not to be understated
It is a 10-speed reversible fan with intake and exhaust, meaning I can pull in cool air at night or when I'm parked in the shade, or keep air circulating without losing heat on cold days
It has a programmable thermostat and a remote control
Another great option is the Maxxfan Mini. This vent is a more buget option from Maxxair, featuring more basic features whilst still including a rain cover.
You could also look at buying a cheaper, 'no name' campervan fan from Amazon. This one is particularly well-reviewed and good value.
Campervan Roof Fans Compared
Here's a table comparing the most popular roof fans for campervans based on key features such as airflow (CFM), power consumption, noise levels, unique features, and cost. These factors are important for helping users choose the best fan for their needs, especially in terms of energy efficiency, noise, and performance.
CFM stands for cubic feet per minute, and is a measure of how much air a fan moves. A CFM of 800-1,000 is enough to create a significant wind in a campervan's small interior, and probably isn't necessary for most people. Meanwhile, a CFM of 300-600 is comparable to a office fan and should be adequate for campervan use.
Model | Maximum Airflow (CFM) | Power Consumption at 12V | Noise Level (dB) | Speed Settings | Unique Features |
900 | 2.6A – 4.0A | 35 – 52 | 10 | Rain shield, reversible, remote control, thermostat | |
920 | 3A – 4.5A | 35 – 55 | 14 | Remote control, reversible, rain sensor | |
800 | 2.5A – 3.5A | 40 – 55 | 10 | Remote control, reversible, rain sensor | |
600 | 2.0A – 3.0A | 40 – 50 | 4 | Compact | |
920 | 2.5A – 4.0A | 35 – 50 | 3 | Rain sensor, reversible | |
350 | 2.0A – 3.0A | 45 – 60 | 1 | Reversible |
Key Factors to Consider:
Airflow (CFM): Cubic feet per minute (CFM) is a key metric for measuring airflow. Higher CFM values provide better ventilation, though the highest settings of some fans are perhaps overkill for most situations. Fans like the Maxxfan Deluxe and Fantastic Vent 7350 offer some of the highest CFM levels.
Power Consumption: Power consumption is crucial for campervans using 12V systems. Most of the fans listed above have a comparatively low power draw, with the Heng's Vortex II and Maxxair Maxxfan Mini being the most energy-efficient at just 2A – 3A.
Noise Levels: Noise can impact comfort, especially when sleeping. The Maxxair Maxxfan Deluxe is relatively quiet, at 35 dB on the lower settings, while budget options like the Heng’s Vortex II can be noisier at 45 – 60 dB.
Unique Features:
Rain Shield/Sensor: The Maxxair Maxxfan Deluxe comes with a built-in rain shield, allowing you to operate it in bad weather, while the Fantastic Vent 7350 has a rain sensor which closes the vent automatically when it detects rain.
Remote Control and Thermostat: Fans like the Maxxfan Deluxe and Fantastic Vent 7350 have remote controls and programmable thermostats for added convenience.
Reversible Airflow: Most high-end fans, such as the Maxxair Maxxfan Deluxe and Fantastic Vent 7350, as well as the Heng's Vortex II, allow for both intake and exhaust functions.
British Standard Ventilation Requirements and Planning Your Fans and Vents (BS EN 1646-1 and BS EN 721)
If you’re building to UK and EU motorhome standards, roof vents and fans aren’t just about comfort; they form part of the safety ventilation required by BS EN 1646-1 and BS EN 721. In simple terms, these standards say that every habitable compartment in a motor caravan must have a minimum amount of permanent, unpowered ventilation, split between:
High-level ventilation: this can be vents high up on your walls but usually takes the form of roof vents and skylights
Low-level ventilation: smaller vents near floor level
For vans with an open-flame gas hob or other non room-sealed appliances (meaning appliances whose gas combustion is completely sealed from the room), BS EN 721 sizes this safety ventilation by the floor area of the habitable part of the van (i.e. the living area behind the cab). The table below shows the minimum free area you need to design in. Free area here means the actual clear opening through the grille, not the outside frame size. Most rooflights and vents list their free area in cm² in the datasheet.
Habitable Floor Area of Van | Minimum Permanent Ventilation in Roof Vents | Minimum Low-level Permanent Ventilation |
|---|---|---|
Up to 5m² | 75cm² (7,500mm²) | 10cm² (1,000mm²) |
Over 5m² and up to 10m² | 100cm² (10,000mm²) | 15cm² (1,500mm²) |
Over 10m² and up to 15m² | 125cm² (12,500mm²) | 20cm² (2,000mm²) |
Over 15m² and up to 20m² | 150cm² (15,000mm²) | 30cm² (3,000mm²) |
Most L2–L3 campervans fall in the 5–10m² band, so you’re typically aiming for at least 100cm² of permanent high-level ventilation. A skylight with “forced ventilation” can cover this on its own; many powered fans can’t, because they seal completely when closed.
Low-level ventilation is usually provided by floor vents or low wall vents (we'll discuss these more later). For a typical 5–10m² van you only need 15cm², which is a relatively small opening, but it needs to be permanent and not more than 100mm above the floor.
Your powered fan then sits on top of your permanent ventilation baseline, massively improving airflow when it’s running, but it doesn’t replace the need for permanent free area.
When you’re choosing between a powered fan and an unpowered skylight, it’s worth checking the datasheets for the quoted “free ventilation area” and making sure that, in combination, your roof vents and floor vents meet or exceed the figures in the table.
Skylights and Unpowered Vents
Skylights and unpowered vents also have a place in campervan ventilation. In our 2023 Roaming Home study we found that 42% of vans had installed a skylight or unpowered vent. Whilst powered vents offer superior ventilation, an unpowered vent or skylight offers some benefits.
Where a powered vent's fan obstructs most light, an unpowered vent allows a lot of natural light in from above. This brightens up your interior more effectively than a side-mounted window. An opening on the roof also provides better ventilation than a window, allowing rising warm air an escape and being more exposed to wind, no matter which direction it's coming from. An unpowered vent also has the advantage of being upgradeable with a fan kit down the line. If budget is an issue, you can start with an unpowered vent and upgrade it later. Alternatively, many vanlifers build their own DIY roof fans by combining an unpowered vent with cheap desktop computer fans.
Be cautious when choosing, as some skylights are simply transparent windows which can't open. In our view, this eliminates the primary benefit of a roof vent, which is ventilation. As it is, a skylight lets in sunlight and therefore heat, and needs to be combined with a shade in hot weather. A skylight which can't open has this same drawback without the upside of ventilation.
Many of the same manufacturers of roof fans also make unpowered vents and skylights, including Fiamma, Dometic, and Thule. We recently installed the Dometic Mini Heki skylight in Shane's new van: check out the review and installation guide here.
Floor Vents
The air that a campervan fan extracts needs to be replaced with fresh air from somewhere. This is a vital component of campervan venting, as keeping cool and comfortable isn't just about the removal of hot and moist air. Rather, it's about establishing a flow of cool, fresh air into your campervan. This is as important for comfort as it is for moisture control; read more about that in our guide on condensation and vapour barriers. A great place to take in cold air is through a vent in the floor, as the air underneath your van is shaded and cooler.
If your fan is at the front of your van, then the floor vent would ideally be at the back, and vice-versa.
Whilst you could use a simple drop-out vent for this job, in cold climates you might regret having a permanent opening in the floor. It's better to have a louvred or rotary vent which you can open and close as necessary. Alternatively, a blast gate valve also works well for this purpose.
Alternatives to a Campervan Roof Vent
Roof fans and skylights aren't the only solutions for campervan cooling. We'll discuss some other options here, including air conditioning.
Fans
Office-style fans are a simple and effective way to improve air circulation within your van. Fans come in various types, including ceiling fans, oscillating fans, and portable fans such as neck fans, handheld fans, table fans, and clip fans. They use significantly less power than air conditioners and can be sufficient for mild climates. Even a couple of USB fans might get the job done.
Air Conditioning
Another way of staying cool in a campervan is with air conditioning. I don’t own an air conditioner, but sometimes in the depths of summer, I really wish I did. In the Roaming Home study, we found that 11% of van conversions had AC installed.
This is a big topic, but in short, air conditioning is a luxury option which is only appropriate for campsite usage due to its high power draw. Of course, air conditioning is by far the most effective way of cooling the inside of your van. Therefore, if your budget and electrical input can handle it, you won't find a better solution. There are a number of manufacturers of 12V DC air conditioners designed specifically for campervans, including Dometic, Velit, and Nomadic Cooling:
Read more about campervan air conditioning in our long-form article on the subject.
Evaporative Coolers
Also known as swamp coolers, these are a cheaper and much less electricity-hungry alternative to air conditioning. Evaporative coolers work by passing air over or through water-saturated pads, causing the water to evaporate and cool the air. The only powered components in an evaporative cooler are the fans and a small water pump, making them much less power intensive than air-con. Evaporative coolers constantly pull in fresh outside air, cooling it on the way, rather than recirculating stale air from inside the van. Finally, the efficiency of an evaporative cooler actually increases as outside temperatures increase, as this promotes evaporation of water. This is in contrast to air con units, which have to work harder as it gets hotter outside.
Evaporative coolers won’t feel the same as air con units. They have a more subtle effect, passing cool, fresh, humidity-controlled air into the room, as opposed to dry, thoroughly chilled air. The cooling effect is less profound, though some say that overall comfort is higher with an evaporative cooler due to their maintenance of a humidity level that’s optimal for human comfort. Their main drawback is the fact that their efficacy decreases as outside humidity increases.
How to Install a Camper Van Roof Vent
Note: Though we are discussing the installation of a roof vent here, the process for installing a skylight, air conditioning, or another campervan fan is the exact same. Refer to the supplies list at the start of this article to make sure you have everything you need.
Step 1: Build a wooden frame to support your skylight
Your chosen vent will be designed for roofs of a certain thickness. In order to bring your van's thin sheet metal to the required thickness for your fan, we'll need to build a frame to support it. For example, for a vent that's designed for roofs 25mm-42mm thick, you'll need to buy wooden battens that are 25mm-42mm thick. The internal dimensions of this frame need to exactly match the dimensions of the hole we cut in our roof.
Measure and cut the wood for your frame
If you're using simple butt joints to build your frame, you'll need:
two lengths of wood the same length as the sides of your roof hole
two lengths of wood the length as the sides of your roof hole + 2x the thickness of the wood
This is because the longer pieces of wood need to fully overlap the ends of the shorter pieces:
If you're using mitre joints, you'll need:
four lengths of wood the same length as the side of your roof hole
Cutting the ends off these lengths of wood at a 45° angle will give you a frame that fits over the hole.
Calculate the lengths of wood you'll need to cut and measure and mark them out. Make sure you're precise in your measurements: measure twice, cut once.
A mitre saw will cut your wood very accurately at angles. A jigsaw works too, but make sure you've clamped the wood securely to your workbench. Once the wood is cut, verify that all your pieces are the right length, and sand any splinters off the ends.
Clamp and glue your frame together
Use corner clamps to set the wood up in the form of your frame. Don't tighten these all the way down yet; keep some wiggle room between the lengths of wood whilst holding the structure in place.
Squeeze wood glue onto the butt ends of the shorter lengths of wood, seat them flush against the longer lengths, and clamp them into place. Don't bear all the way down on the clamps one at a time, as the tension on one joint can pull the others out of position. Instead, get each clamp mostly tight, ensure everything's aligned, then go back around and tighten the clamps all the way.
If this frame is going to be hidden in the layers of your roof, you can secure these joints with screws. If you decide to do this, drill pilot holes first to prevent splitting of the wood before driving the screw home. An impact driver counter sinks the screws without needing to use a counter sink drill bit first.
With the wood glue in place and the screws in, leave the frame clamped together for your glue's specified setting time.
Step 2: Cut the hole in your van's roof
Once the glue's set, unclamp the frame and take it out to your van along with:
painter's tape
tape measure
non-permanent marker or pencil
drill with 25mm hole saw attached
tapping and cutting fluid
metal paint
jigsaw with metal cutting blade attached
metal file
Mark the outline of your hole and your hole saw locations
Set the wooden frame on the roof where you want the skylight to be. Check that the exterior frame of the skylight won't be obstructed by anything structural when it's installed around the hole, and make sure you won't be cutting into anything structural on the inside of the van.
When you're happy with the location of your hole, lay down some painter's tape where you're planning to cut. Use a set square to draw the outline of your hole onto the tape. Once the outline is drawn, verify that the dimensions are accurate.
Your roof vent might call for a square hole with round corners; if that's the case, you'll need to use a hole saw to drill the initial corner holes. Your vent's instructions will specify the dimensions of these corner holes and where to place them.
Cut out the corner holes using your hole saw
Get your ear protection on and, using an HSS drill bit for pilot holes and a 24mm bi-metal hole saw for the main hole, cut holes at the marked points. Use tapping and cutting fluid to lubricate the hole saw, and use a pulsing action to minimise heating.
You'll be connecting these four holes with straight jigsaw cuts, and the end result will be a rectangular hole with rounded corners.
Connect the corner holes with jigsaw cuts
When cutting with a jigsaw, use a low setting and move slowly and steadily. High saw speeds cause heating, warping, and breakage of the blade. Pushing too much with the saw causes it to snag and jump, making for a jagged cut and broken blades.
File and treat the edges of the hole
Peel off the painter's tape, and wipe away loose swarf and metal dust with a rag. Use a metal file to file down the perimeter of the hole until it's smooth and free of burrs. Take a moment to sweep or hoover up any metal shavings on the inside of the van.
All cut metal needs to be treated to prevent rust. We used anti-rust zinc spray because it dries quickly and is very easy to to use. Apply it all around the cut metal edge, ensuring full coverage.
Let the paint dry before moving on to the next step.
Step 3: Prepare the edges of the hole for the skylight frame
Most vans have ribs and runnels that traverse the length of the roof. These ensure drainage of rainwater, but create an uneven surface that isn't much good for the mounting of a skylight. There are a few ways to create an even, uniform surface for your roof vent. One way is to precisely cut a wooden adapter which slots into the runnels, but a simpler way is to use mastic/butyl tape.
Mastic/butyl tape is a waterproof, malleable tape that has a texture something like plasticine. This texture makes it easy to mold, and means it provides a slightly soft surface for your skylight frame to press snugly into. Lay down strips of mastic tape in the grooves in the roof, pressing them into each other and building them up until they match the height of the ribs. A couple more layers on all four sides will create a uniform surface of the same height.
Step 4: Stick the outer half of the skylight to your roof
Run a thick bead of campervan sealant in the appropriate location on your outer vent frame's rim. Be liberal in your application of sealant, ensuring the bead is consistent all the way around, with no gaps.
With your sealant in place, fit the skylight into the hole you cut (make sure it's facing the right direction). Press the skylight down firmly on all sides and corners, squeezing it into the mastic tape. You should see sealant oozing out a little bit all around the perimeter.
Step 5: Fix the inner frame to the outer frame
On the inside of the van, put the wooden frame in place around the outer skylight frame's flange, which should now be projecting into the van. Fit the inner skylight frame around the flange, over the wooden frame. Make sure everything fits correctly.
Your vent's installation instructions may require drilling screws through the van's metal to join the internal and external frames together, or they may just screw directly to each other.
As you drive the screws from the inside, they should bite into the outer frame and pull it inward as they tighten down. For this reason, it's best to drive opposing corner screws first, and only tighten them to 70% or so. Next, drive the screws along the edges of the frame, also only to 70%. Once all the screws are in and pulling the frames together, you can go around screwing them to full tightness.
If you're screwing through your van's metal, self-tapping screws will make this much easier as they can be screwed directly into the roof. Put a little bead of adhesive sealant on top of each screw head after they have been drilled in to seal the screw holes.
Step 6: Fix the trim plate to the inner frame
Again, this step will vary depending on the exact construction of your vent. You might be screwing your trim into your wooden frame, or it might be a job using sealant.
Step 7: Finishing touches
Get back onto the roof and check that the outer frame has been pulled tightly into the mastic tape. The sealant you applied is likely to have been squeezed out around the frame as everything was tightened down.
Depending on the exact design of your vent, you might like to add a final bead of sealant around the gap between the vent frame and your van's roof. Pay attention to whether win is likely to blow water into any open gaps where it could then sit stagnant, and consider sealing these up. A squeegee tool or wet fingertip is perfect for smoothing any excess sealant around the edge of the vent frame. Check out our article on camper roof sealing for more information on sealants and how to use them.
Give everything a final clean with paper roll or a microfibre cloth, peel the protective plastic film from the glass, and admire your handiwork.
Conclusion
A roof fan (combined with floor-level venting) is a comparatively cheap, electricity efficient solution for campervan ventilation. Whilst air conditioning and evaporative coolers might provide more noticeable cooling, they're far more expensive and use more electricity. With a roof fan, you can stay cool in most climates without depleting your leisure batteries.
Don't forget to check out our top picks for campervan roof fans, including the Maxxair Maxxfan Deluxe and Mini. Our favourite unpowered vent is the Dometic Mini Heki: our review and installation guide has the details.
Don't forget to subscribe to The Van Conversion Newsletter for everything you need to get started with your own van conversion (we'll send you a free wiring diagram when you join).
If you're looking for some guidance with your van conversion, you might be interested in our book Roaming Home, or in our online course The Van Conversion Mastery Course. You'll learn directly from our founder Shane how to convert a van into your dream home - no prior experience needed. Shane also offers one-to-one consultations, where he'll help you with any aspect of your build in a face-to-face video call. All consultations come with a free copy of Roaming Home and our Diagram Pack.
Finally, our Van Conversion Ultimate Guide lays out the whole van conversion process in easy-to-follow sections with tools, materials, and step-by-step instructions. It's the perfect companion for your van build.
Until next time.