Insulation Measurement

" The problem with insulation is flow of air inside. For example, an un-insulated air mattress has a lot of internal airflow, so it doesn’t provide very much insulation."

Jerry – I infer from this that sewing a criss-cross pattern into my synthetic quilt will improve warmth by reducing internal air flow. Is that correct?

Andrew

No – quilting would create thin places so it would be worse

I speculate that in my test, since the insulation was horizontal, the air flow was vertical. You could have some insulation, then a layer of something that impeded air flow, then another layer of insulation, but the layer of something would weigh more than anything gained.

When I put a layer of eVent on top it improved the insulation. I speculate that that impedes air flow inside the insulation. So, by choosing the right material for the top you could improve your insulation. I think eVent weighs too much so you'de be better off with lighter weight fabric and a little more insulation.

But then what about if it's windy?

I think I have rasied more questions than answers : )

An additional test beyond the "Squishing" test would be a "stuff sack" test. This would mean that test "garments" would be stuffed into a sack at a set pressure, sealed and let set for 3 or 4 days (or test for EACH day and re-stuff). Then run the base tests included here again. (Shelled tests need not be done again.) In this test I feel that most, if not all, synthetic insulations would suffer greatly.