Product innovation over the years has seen the introduction of several different types of spray foam insulation. Primarily in residential and commercial construction, open-cell and closed-cell spray foam is used while high-density spray insulation is used as roofing foam in commercial or industrial construction. Open-cell sprayed-in foam insulation, a soft low-density material, is typically used for interior applications such as wall cavities, underside of roof decks, attics, basement walls and crawlspaces. The open cell structure of low density foamed insulation allows for moisture permeability to help contribute to moisture management and bi-directional drying of the wall assembly.
Heat which is created elsewhere that is transported by means of a fluid, such as water or in our case air. Spray foam insulation's most important attribute is the ability to air seal creating a custom airtight envelope within the building structure. The added benefit to air sealing is the ability to block convective heat transfer from interior to exterior during heating months and vice versa during cooling months, as the heat cannot escape through gaps in the buildings envelope without the aid of air movement from infiltration as a means of transport. https://www.youtube.com/v/ggLAUsiuI_o&feature=share
We have a 22 year old home located in southeastern georgia where the humidity is very high. In the past 2 weeks our floors have started buckling all over. We have a vented crawl space and the old insulation is drooping from moisture and the wood is wet. We are debating between the "encapulation" method or the spray foam method to repair this issue. Which would you recommend?
Note: The practice of foam insulating the attic has raised eyebrows in the building industry because "standard" roofing techniques call for the attic to be ventilated; however, in a vented attic situation it will become approximately 130 degrees in the summer. There's no reason for an air-conditioning and vent-ductwork to have to work in that type of severe conditions. By applying Icynene right on the underside of the roof deck, the severe temperatures no longer exist in the attic. In short, the attic is now a "conditioned" space of the house that is just as comfortable as any other room in the home. This is called a "Compact Roof", which means you can frame right up against it. The one drawback of using expanded foam on the inside of the roof is that this will cause the temperature of the shingles to rise, but how much is not yet known. And how much damage a rise in temperatures could cause is debatable.