Our ambulance came panelled and insulated. (Which we thought was great, when we bought the van: The good things about buying an ambulance as a base vehicle.)
Sadly, the old insulation we had in Campy Van- Rockwool haphazardly shoved in behind panels- was inadequate and prone to condensation. It needed attention if we were to enjoy using the van in more extreme temperatures. Therefore, the insulation has actually been the main reason (besides the excess weight) for stripping back Campy Van to the bare bones.
I weighed up the different options of insulation for a campervan:
|Type of insulation||Pros||Cons|
|Sprayfoam||– great insulating properties|
– no airgaps and places for condensation to get to metalwork
– professionally done, so you don’t have the hard work
– once it’s done, it’s very hard to remove
– cold bridging
|Closed Cell Matting||– light weight|
– very good insulating properties that improve with thickness
– a DIY job
– fixed to the van body, so no squeaking
– relatively inexpensive
|– it’s a long job|
– can leave gaps for condensation to form on bodywork and lead to hidden rusting
|Board insulation||– cheap|
– readily available in different thicknesses
|– prone to squeaking as it’s wedged in spaces|
– not fixed to the bodywork, so condensation and hidden rusting can be a real problem
|Silver foil||-cheap and easily available||POINTLESS:|
– it has very little insulation value, it’s insulation properties depend on an airgap, which then leads to condensation issues
We decided to go with the material professional van converters tend to use: a closed-cell matting, like yoga mats. It’s manufactured in Europe, by Trocellen.
Unfortunately, our choice didn’t come as a self-adhesive option, though that can be ordered apparently in larger quantities.
Our Campervan Insulation Approach
For insulating the van I’ve taken a three-pronged approach:
– expanding foam injected into hard to reach areas
-15mm closed-cell insulation matting glued to the body of the van
– finally, 5mm silver foil backed Polifoam covering all surfaces, bonded to the first layer and sealed around the edges with tape.
Using Expanding Foam
A big issue with insulating a campervan can be cold bridging– where the insulation is inadequate and cold spots appear, which then causes condensation in those points.
Condensation on a metal body is bad: it leads to rust.
Rust is especially bad, if it is not visible, hidden behind panels.
Campy van has ribs, which, if I’d have insulated the over with the 15mm closed-cell matting, I’d have eaten into our living space.
I decided to tackle insulating the ribs with expanding foam.
Expanding foam was injected in the small crevices, behind metal supporting studs and in stud cavities.
The van- a long-wheel-based Peugeot Boxer- has gobbled up 10 cans of expanding foam.
There are two versions of spray foam available from your hardware store: one that comes with its own applicator and one which you need an additional spray gun for.
I used the expanding foam with a special applicator gun. The gun is a must: the application is much easier to control, the result is more precise. (This is something I learnt the hard way, by buying the cheaper spray version and struggling to control the quantities coming out, making a right mess.)
After injecting the hard-to-reach areas with expanding foam, I had to wait 12 hours for the foam to go off and harden. Then came the tedious task of carving off the excess which flowed into the wrong place. This took another couple of hours.
Expanding foam had to be applied in a couple of stages:
- large cavities needed to be filled in a couple of goes, as a single application would mean that the core would not set, but remain a gooey mess doing nothing for insulation.
- some cavities needed to be filled before the first layer of closed-cell insulation went up, as afterwards I wouldn’t be able to access them to apply the expanding foam.
- I’m not always precise with measuring and had left little gaps in places between the closed-cell insulation and the metal ribbing. I applied tiny squirts of expanding foam into those crevices too.
I probably spent a day and a half applying the foam and then carving it back.
Base insulation with 15mm closed cell insulation
The 15mm polyfoam is stuck onto all the flat and accessible panels of the van. I’ve used a strong (and very nauseating) adhesive to hold it in place.
It’s a fiddly job measuring, cutting, glueing panel, glueing the insulation and then adjusting it into position.
Initially, I was cutting the matting straight off the roll, then I realise I was struggling to make straight cuts vertically.
I started using a large table for measuring the insulation out, cutting and applying glue to it there. I’d measure it up, then cut along the line with a long ruler joining my 2-3 measurements along the length of the cut. I used a sharp Stanley knife to cut.
As I gained experience, I was then cutting lots of panels at once, then moving onto the glueing phase. It made more sense than running back and forth between measuring, cutting, glueing. The glue was going off or not being ready to stick yet. The batch method worked much better.
The process of insulating the panels with this layer took about 3 full (wo)man-days in total. This was stretched over a 2 week period, while I also tended to other tasks.
The closing layer: Reflective closed cell insulation
The 5mm silver-backed foam insulation was the final layer to apply. To be truthful, this was a task I had dreaded most: I had electric cables and other elements – screws, posts, etc to consider.
The silver foil face was used facing into the van.
I put it up with the combination of glue to all the metal elements and welding – with a heat gun- to the 15mm insulation already glued to the walls. In places it looks super, following the contours of the van’s wall beautifully, in some places it’s sagged where I didn’t heat it well enough or didn’t press it into the right place to weld the two layers together.
All in all the task was more difficult than I’d anticipated, yet went quicker. It took about a day and a half.
I’ve taped all seams.
Insulating the Floor of the Campervan
The base van floor is ribbed for added strength and it is amazing how much the thin metal sheet on it can withstand!
The ribs, that provide the strength of the van’s flooring, are also the bane of one’s life when insulating the floor. To overcome some of the height difference in the ribs, I cut and glued strips of the 5mm closed cell insulation to the floor.
I then used the same 15 mm closed cell insulation on the flooring.
I laid this in panels across the floor and slightly up the wall, welding it to the 15mm insulation on the wall, then I overlapped the 5mm insulation down over this floor insulation down to the wooden floor.
It seems counterintuitive to use a flexi material as insulation and I know that where the ribs are my floor won’t have the same insulation value as where the valleys are.
I know that the closed-cell insulation will lose a lot of its insulation value as the wooden floorboard compress it! However, I wasn’t willing to risk the squeak of a rigid insulation board.
I hope, however, that the level of insulation will still be adequate.
For the flooring I’m using a 9mm compressed plywood panel, which is usually used in lorries for flooring. This will have a slight insulating value too and we’ll possibly add a vinyl flooring over the top.
If next winter proves my floor to be too cold, I’ll add some carpets, which can easily be removed for cleaning.
This is what happens when you finish insulating the van: