Thermo Liner vs Celotex or Thermal PIR Board?
R Value + Celotex and the inefficient arguement!
Celotex/PIR is cheap and effective in houses but it’s not suited to vans.
R value is directly related to thickness so comparing 7mm of Dodo Thermo Liner with 50mm of Celotex is pretty pointless.
The best insulation is the one that can be fitted properly in the location and can match the contours of the vehicle. So in a small van thick Celotex would be cut into small sections with lots of gaps killing it's performance AND WILL eventually cause you significant issues as moisture & condensation will find its way behind the boards and to the thin steel panel. You hear of many self builders using bubble wrap as insulation. Again this is totally useless in a van as it gives little to no heat retention being a reflector foil. Sealed closed cell foam against the contoured panels with good ventilation will be your friend...
A closed cell foam liner is rarely rated with an R-value like thick insulation layers as this is not its primary function. A foam liner is designed to soundproof and prevent thermal transfer through a steel panel and prevent dramatic temperature swings and lower the possibility of condensation formation. In this instance where the application limits the thickness you can use (so you cant increase R with a thicker layer), you want something with good thermal resistance but also able to contour and follow the shape of the van. Closed cell foam is great for this with a thermal resistance of 0.034 W/mK.
If you wish to have heat retention with a good r-value in the van you must use a thicker insulation over the liner. Our recommendation in a vehicle environment is to use a recycled plastic PET type such as Dodo Thermo Fleece which is safe to handle and will not absorb moisture in high humidity conditions like some wool based products.
If you're on a budget, it may be possible to run a block of board on the floor space with a liner on the walls however you are missing on the sound isolation and running the risk of moisture build up if it's not fully sealed off. A much better fit would be the use of Super Liner or Dodo Duo. Thermo Liner isn't a suitable application on the floor area and will come down to budget. Some builders choose not to insulate the floor at all still with a CCF such as Thermo Liner Pro on the walls and roof space with a fleece lining as mentioned previously.
So it's never easy to argue. Too many variables. The best insulation is the one with good thermal resistance and can be fitted to the best affect within your budget.
We offer a wide variety of product which are fully appropriate for use within a van conversion here and come with years of knowledge in the industry
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