Foam board insulation and vibration?
Hi folks, I'd appreciate hearing your thoughts on this. For my new van build, I was planning to do a floor of foam board (the 4x8 blue or pink stuff used in S&Bs), topped with 1/4" plywood, then sh...
Forum Discussion
Is there anything underneath the foam?
If you made a plywood and foam sandwich, plywood bread and foam filling, and had it well glued ("laminated") together, you would make a surprisingly stiff and lightweight floor. This works because the stresses in a beam are concentrated at the surfaces; the middle does relatively little work. (I-beams work on the same basic principle, with the middle web serving mainly to keep the upper and lower chords in place.) Laminated floors of this general description are not uncommonly used in RVs. Instead of the lower plywood, it would also work well if you could attach the foam to the floor of your van securely all over, which might be practical if the floor is flat rather than having corrugations or whatever.
The foam at any rate is not subject to point loads, as the plywood spreads it out, so I would not expect it to break down from vibration etc. very quickly. If the foam is unsupported on the bottom, the plywood needs to be heavy enough to carry the weight on the floor on its own, and quarter inch plywood is probably inadequate for that.
If you made a plywood and foam sandwich, plywood bread and foam filling, and had it well glued ("laminated") together, you would make a surprisingly stiff and lightweight floor. This works because the stresses in a beam are concentrated at the surfaces; the middle does relatively little work. (I-beams work on the same basic principle, with the middle web serving mainly to keep the upper and lower chords in place.) Laminated floors of this general description are not uncommonly used in RVs. Instead of the lower plywood, it would also work well if you could attach the foam to the floor of your van securely all over, which might be practical if the floor is flat rather than having corrugations or whatever.
The foam at any rate is not subject to point loads, as the plywood spreads it out, so I would not expect it to break down from vibration etc. very quickly. If the foam is unsupported on the bottom, the plywood needs to be heavy enough to carry the weight on the floor on its own, and quarter inch plywood is probably inadequate for that.
