Closed-Cell SPF At 2-lbs per cubic foot closed-cel l SPF,alternately cal led 2-lb foam, is approximately four times denser than open-cel l foam.Once set, the material remains rigid and more difficult to compress by hand-appl ied pressure. In compression closed-cel l is ten times strong...
There were some figures in a report on a cruder life-support set up written in 1953. This used Chlorella algae, which isn't quite as good as Spirulina since it has an indigestible cellulose cell wall. The figures assume a Chlorella culture density of 55 grams per liter of water and a d...
The closed cell spray polyurethane or polyisocyanurate foam adhesive acts to uniformly distribute the wind load from the sheathing to the beams, thus increasing the uplift load considerably. Testing has shown that typical uplift loads increase from approximately 70 pounds per square foot to ...