One of my neighbors just finished insulating a 32X40 machine shed last week. He went with the old school pink fiberglass rolls, as they were right at 1/2 the cost of the spray in for the same R value. that was calculating material costs only, as he was planning to do either job himself. He did not factor in the extra time it took, which was considerable. I'd guess 3 times as long to install 'standard' insulation vs the spray in? Maybe 4 times?

Another consideration in his case was that he had a conventionally constructed shed, with 2X6 wall studs at 16" centers - so rolled insulation was a viable solution. In your case you'd either be going with the 4X8 sheets of polyethylene foam or the spray in solution. The foam sheets install easily, I've used them in several applications.

Dale

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"When tempted to fight fire with fire, remember that the Fire Department usually uses water." - anonymous