Van insulation options: 3 choices for DIY builders

What are the main van insulation options and which is best for a DIY builder?

The main options are rigid foam board, closed-cell spray foam, and natural wool. Foam board balances performance and DIY friendliness. Spray foam gives the highest R and best air seal but is messier. Wool is easiest around curves and helps with moisture but has lower R per inch.

How much R-value do I need for a campervan?

Aim for higher R in the roof and floor than the walls. A common DIY target is R-8 to R-12 total in the roof and R-4 to R-8 in walls and floor, adjusted for your climate and available cavity depth.

Will insulation stop condensation in my van?

Insulation helps but you also need good ventilation and correct vapor control. Closed-cell foam blocks moisture movement; breathable insulations like wool help buffer humidity but require ventilation to avoid trapped moisture.

Can I mix insulation types in one build?

Yes. Many builders use foam board where depth is tight, wool around curved areas, and targeted spray foam for gaps. Just ensure transitions are sealed and you account for differing vapor behaviors.

How long do DIY installs usually take?

Expect 1–2 days for foam board or wool in a typical van, and a half day to one day for spray foam application plus cleanup and cure time. Prep and trim add extra hours.