Van insulation: complete DIY conversion installation guide

Want to relax in your campervan without sweating or shivering all night long? Then van insulation is an absolute must!

In this DIY guide to van insulation, you will find:

• Things to consider before insulating a campervan

• How much to budget for van insulation

• The best insulation for van conversion (the pros and cons of each)

• Step-by-step instructions on how to insulate a van

• How to ventilate your van

• How to make money from your DIY van conversion in Australia

By the time you’re done, you’ll have a comfortable campervan conversion that keeps you cool in summer and warm in winter!

Earn up to $10,000 a year by hiring out your campervan - sign up to Camplify today.

Campervan insulation: Step-by-step instructions

1. Considerations for insulating your van

There are six factors that you should consider before installing campervan insulation:

• Radiation

• Conduction

• Convection

• Heat resistance

• Absorption

• Plumbing

Heat resistance

Every insulation product has an R-value, which measures its resistance to heat conduction. The greater this metric, the more effective the material is at slowing heat transfer.

To minimise the thickness of the walls and save space inside your campervan, use insulation with a high R-value.

Conduction

Conduction occurs when heat moves through solid surfaces, like your van’s walls and ceiling. On warm days, conduction transfers heat through the metal body of your van and into the cabin. And on cold days, it can also transfer heat out of your van.

Insulating your van’s walls, ceiling and floor will hinder heat transfer via conduction, meaning you have better control over the internal temperature.

Convection

Heat inside your van is continuously rising due to a natural process known as convection. As a result, insulating your ceiling is key to retaining warmth inside the cabin.

However, remember, the thicker your roof insulation, the more headroom you will lose.

If you find it is too hot in your campervan and you want to extract some of the rising heat, you should install a ceiling vent fan.

Radiation

Radiation occurs when heat moves through the air (e.g. heat coming off of a fire.) Windows are the primary source of radiation in your van. Sunlight streams through the windows and transfers heat into the air.

During the warmer months, you can deflect radiant heat away from your van with reflective window coverings. And during colder months, you can flip the coverings around to retain heat inside your van.

Absorbance and evaporation

Insulation is also important for absorbing and evaporating the amount of moisture inside your campervan.

Given that your van conversion will consist of several insulation materials, try to include at least one material that naturally absorbs and evaporates moisture in the air (e.g. sheep wool). Doing so will protect the metal frame and surfaces from rusting.

Plumbing

You will also have to insulate your campervan water pipes if you want to camp in freezing conditions. If the water pipes under your campervan freeze, this can cause them to crack and leak - a financial nightmare to fix.

2. Budget for van insulation

In Australia, it will likely cost $400 - $800 to fully insulate your campervan conversion. This depends on how well you want to insulate your campervan - if you only want to use your campervan in summer, you probably won't require as much high-quality insulation.

Campervan insulation costs may include:

• Sheep Wool Insulation (for walls): $200

• Rigid Foam Board Insulation (for floor and ceiling): $100

• Spray Foam (for hard-to-reach places): $50

• Internal Thermal Blind Set: $200

• Piping Insulation (optional): $100

• Additional Soundproofing (optional): $200

3. Choosing van insulation materials

https://www.youtube.com/embed/l_ZYi6AcPmU

Sheep wool insulation

Recommended use: Walls, ceiling and door panels.

Sheep wool is the gold standard for van insulation.

Eco-friendly, non-toxic and mould-resistant, it’s also renowned for its breath-ability and moisture management. Sheep wool naturally absorbs and evaporates moisture in the air, protecting your metal wall from condensation as it insulates. That means you don’t have to fret over correct installation, which is a major plus for any DIYer!

And to top it off, sheep wool even has sound-deadening properties for peaceful camping trips.

However, there are disadvantages to sheep wool. It is more expensive than other insulation materials, so it’s not the best bet option for budget van conversions. And as it has a relatively low R-value, you’ll need to pack it on thick compared to foam boards or spray foams. That means more costs and possibly less interior space.

The advantages and disadvantages of sheep wool van insulation include:

• Absorbs and evaporates moisture

• Easy to install

• Sound-deadening properties

• More expensive than other insulation options

• Lower R-value than other insulation options

• Thickness can take up more internal space

Foam board insulation

Recommended use: Walls, ceiling, floor and door panels

Rigid foam boards are a great option for insulation, especially if you don’t have much money to spare on your van conversion. It’s the most cost-effective insulation material, boasting a high R-value without taking up too much living space or blowing your budget.

But be warned: correct installation is critical with foam boards. If you’re not careful with its placement, condensation can get trapped behind this insulation, which will eventually lead to rusting.

There are three different kinds of foam boards that are typically used for campervan insulation:

• Polyisocyanurate Foam Boards: Polyiso is a top choice for wall and ceiling insulation in your van. While more expensive than other types of foam board, it has the greatest R-value. It also tends to be foil-faced on one side, serving as a radiant heat barrier if installed with an air gap.

• Extruded Polystyrene Foam Boards: Extruded polystyrene (XPS) is excellent for insulating your van’s floor. Thanks to its high compression strength, you can stand on top of a sheet as thin as 1.27cm without damaging it. This form of foam board also has a high R-value, but is slightly cheaper than polyiso.

• Expanded Polystyrene Foam Boards: Expanded polystyrene(EPS) is similar to Styrofoam, yet many subtypes have a foil-faced side for radiant heat deflection. While it has a lower R-value than other foam boards, it’s affordability makes it a strong choice for budget builds.

The advantages and disadvantages of foam board van insulation include:

• High R-value

• Affordable

• Thin (doesn’t take up much internal space)

• Water-resistant

• Tricky to install

Spray foam insulation

Recommended use: Gaps, nooks and crannies

Spray foam is a lifesaver when insulating those tiny, hard-to-reach spaces. Covering irregular surfaces in seconds, you can ensure that all gaps in your insulation are sealed properly.

It is possible to use spray foam insulation throughout your entire van. However, it’ll cost you heaps (you’ll have to purchase a kit) and make a serious mess if you’re a first-time sprayer. That’s why we recommend reserving its use for any voids between your foam boards.

The advantages and disadvantages of spray foam van insulation include:

• High R-value

• Easy to install in nooks and crannies

• Water-resistant

• More expensive than other insulation options

Fibreglass insulation

Recommended use: Door panels

The dead space inside your door panel can be filled with fibreglass for extra insulation. However, this is not the best option and we do not advise using fibreglass insulation for any other parts of your van.

With the vibrations of a moving van, this particulate insulation can gradually degrade and release harmful molecules over time. Fibreglass is an irritant, so you don’t want to inhale or touch it in any way.

If you decide to install fibreglass, make sure to cover it with bin liners. That way, you can stop it from absorbing water and block nasty particles from entering your living space.

The advantages and disadvantages of fibreglass van insulation include:

• More affordable than other insulation options

• Absorbs water

• Lower R-value than other insulation options

• Dangerous to handle

Reflective foil insulation

Recommended use: Windows and windshields

Windows are by far the biggest culprit for letting heat in and out of your van. If you don’t insulate the glass panels, there’s almost no point in insulating any other part of your campervan.

Foil insulation is the easiest and most affordable way to insulate your campervan windows. Either buy reflective foil sun shades or make your own out of insulation foil. Alternatively, attach tinted film to your windows. This will help to keep out the heat and give you an added layer of privacy during the day.

When using the reflective foil sun shade on hot summer days, keep the reflective side facing outward to reflect radiant heat away from your van's interior. In cold conditions, flip the sun shade so that the reflective side faces inward and traps the warmth inside your campervan.

Note that you can also stick insulation foil to the inside of the van’s metal frame to improve the overall performance of your insulation set up.

Sound-deadening

Recommended use: Walls and floor

Installing sound-deadening material in your van conversion will reduce the verberations and vibrations in your van whilst also helping to prevent sound from entering and leaving the campervan.

For the best results, it is recommended that you use a butyl sound-proofing product such as Dynamat. However, you do not need to buy a lot of this material. You only need enough to cover one-third of each wall and the floor.

Van insulation summary

Sheep wool insulation:

• Walls

• Ceiling

• Door panels

Foam board insulation:

• Walls

• Ceiling

• Door panels

• Floor

Spray foam insulation:

• Gaps

Fibreglass insulation:

• Door panels

Reflective foil insulation:

• Walls

• Ceiling

• Door panels

• Floor

• Windows

Reflective foil insulation:

• Walls

• Floor

4. Install the van insulation

https://www.youtube.com/embed/hj8Y6jlx0KU

Once you’ve chosen which type/s of insulation you will use, watch our video guide to installing insulation in your campervan conversion. Usually, the process follows seven simple steps.

A. Create templates

Create templates by placing pieces of cardboard on the walls, ceiling and floors and cutting to shape. Each template should fill the area between the metal ribs of the van.

B. Trace and cut the templates

Place the cardboard templates over the insulation material and trace the outline using a marker pen. Cut the insulation material around the tracing.

C. Install reflective foil insulation (optional)

Use an adhesive product like Kwik Grip to stick reflective foil to the internal metal frame of the van, covering all the flat areas between the metal ribs. This is also particularly handy for insulating the wheel wells.

D. Install sound-deadening liner (optional)

Measure how much soundproofing material you require to cover one-third of the walls and floor in your van. Stick the sound-deadening liner at regular intervals throughout the inside of the metal frame.

E. Pack in insulation

This step depends on what type of insulation material you use to fill out the cavities in the walls, ceiling and floor.

If you are using sheep wool, you can loosely pack it into the gaps between the ribs in the metal frame.

If you are using foam board or fibreglass, cover the back of the panel with an adhesive product like Kwik Grip. Press the panel against the metal frame, making sure that it conforms to the curves and sticks.

F. Hold the insulation in place

Use masking tape or a piece of lumber to hold the insulation in place in the metal frame. If you used adhesive, leave it to dry for a few hours.

G. Fill in gaps with spray foam insulation

Once all the insulation panels are installed, fill in any remaining gaps or hard-to-reach places by spraying expanding foam insulation. Wait for the foam to dry before cutting off any excess with a knife.

5. Add ventilation (and an optional vapour barrier)

A vapour barrier can be added over the top of your insulation to protect the metal body of your van from moisture, condensation and rust. However, a vapour barrier is not strictly necessary and some van owners argue that it might actually increase moisture build-up by creating a pocket that traps condensation if not sealed correctly.

Regardless of whether you include a vapour barrier or not, you should definitely install ventilation in your campervan. Most van conversions have a vent fan in the roof that helps maintain a comfortable temperature and draws moisture out of the air.

You can learn more about installing ventilation in your van conversion with our guide to roof ventilation and our guide to DIY van conversion in Australia.

Make a return on your campervan conversion

Now that you know how to add van insulation to your DIY conversion, you’re ready to venture into any climate!

But what about when your road trip comes to an end and your campervan is sitting idly in the driveway?

Don’t let your van gather dust. Earn a return on your investment by hiring it out through Camplify!

Camplify makes it easy for holidaymakers to arrange campervan hire in Australia.

Why Camplify?

Each year, heaps of Aussies earn up to $10,000 by hiring out their campervan through Camplify. It provides a quick and easy way to generate long-term passive income and earn a return on their investment.

And the best part is that Camplify takes care of many of the expenses involved in hiring out your vehicle, including:

• Comprehensive hire insurance.

• 24/7 NRMA nationwide breakdown cover for hirers.

• Dedicated customer support.

If you’re interested in joining Camplify as an owner, try our earnings calculator and see how much income you could generate each year by renting out your unused campervan!

Disclaimer: This article is intended as a general guide only. Please do your own further research before installing your campervan insulation.