Stop making the same repairs using less reliable products that are not EPDM based, are not UV and ozone resistant, and do not have flexibility built into the material (causing them to crack). EPDM rubber will expand and contract with any surface as seasons change, and will not crack as a result of temperature changes. Other products will begin to bubble and crack in less than two years.
Thank you, Allison. We have a split system unit (actually 5) with the heat being propane. The foam guy said that it needed ventilation, so completely sealing the attic wouldn't be a good idea. It sounds like you are saying that the systems need to be vented out of the attic or replaced with some type of closed system. But I shouldn't bother spraying if the plan is to leave the soffet vents open. Is that correct?

Spray Foam Attic Insulation

Allison--would be very interested in your take on the GHG issues of foams, which have received lots of smart commentary recently. To highlight a few: architect Jesse Thompson's comments on Tom's Good vs Bad post on Energy Circle, the very thorough piece by Alex Wilson on Green Building Advisor and Michael Anschel's cautionary diatribe on Remodeling. 
For maximum durability and leak resistance, we recommend that two coats of topcoat be applied at 100 sq. ft. per gallon, or a minimum of 20 mils dry coating. If two complete topcoats are not applied, always apply two thick coats to problem areas such as scuppers, drain areas, ponding areas, seams, and repaired areas. Avoid using Elastek Solar Magic™ or The Shield™ on ponding roofs. Clean skin and tools promptly with water.

Spray Foam Attic Insulation Cost

c) Make sure that the over expanded access is properly removed from the walls. We had a junior cutter taking too much off by bending his saw into the cavity. Look closely at the inside wall corners, and ceiling/wall corners to make sure that the foam is properly removed flush with the studs. If it has not been cut back flush it may lead to uneven drywall finishes .
a) Make sure that your house has been well heated prior to installation because the foam expands at different rates as it hits surfaces with different temperatures. If it is cold outside the sheathing may be much colder than the studs consequently the foam may expand more from the sides of the wall cavity creating air pockets in the wall cavity. This can be minimized by an experienced installer.
Today’s “third generation” of blowing agents have a GWP of 700 to 1000 which is still remarkably high considering water/CO2 has a GWP of 1. However, innovation from some chemical manufacturers like the Chemours Company have introduced the next generation of HFO blowing agents such as Opteon 1100, which significantly reduces the GWP impact when using closed-cell spray foam insulation products.
SPF insulation applied by professionals is usually described as either a high- or low-pressure foam and is available as either open- or closed-cell. Each type has advantages and disadvantages depending on the application requirements. The comparison chart below can be helpful in explaining or understanding which type of SPF insulation is best suited to a specific application.
once the foam is installed correctly, it is a inert plastic not much different than the foam cushions you sit on. there is not a health rick unless you have off ratio uncured foam that has not mixed properly. the foam is absolutely a health risk in its raw forms before it is mixed and cured. You should not be in the building without proper respirators and eye protection. The spray foam industry should be controlled and regulated by the same standards, testing and inspections that framing ,electrical and plumbing are. until that happens then you will have idiots with spray rigs ruining peoples homes and ruining the market for honest foam contractors that know how to price a job fairly and complete it correctly.

EPDM (Liquid Roof), (Liquid Rubber) Ethylene Propylene Diene Monomer. Liquid Rubber is available in White, Black Or Grey. The RV product Liquid Roof is available only in white. However, you can customize the color by adding no more than three ounces per gallon of an universal colorant (Glycol Colorant for light colors and for medium to heavy colors use a solvent based colorant available at most paint stores). If the desired color is still not achieved you may add up to ONE more additional ounce of colorant. Once the colorant is added and color achieved then you add catalyst and mix and you are ready! The Liquid Roof coating is specifically designed for RVs and trailers and mobile homes; items that are in motion. Liquid Rubber, the commercial product, is available in white or black. Custom colors are available for orders over 100 gallons. Approved Uses for Liquid EPDM Rubber.
I recently did a remodel project for my basement using spray foam insulation. The original builder has used fiberglass, but I wanted the best insulation i could find. We chose closed cell foam because it blocks moisture from getting into the house. It took one day to install and was fumey for about 3 hours. It was pretty cool watching it being done. It comes out as a liquid and then expands rapidly into a foam. It's quick! Then they took a types of saw to shave it flat with the wall studs so we could then go ahead and drywall.

Roof Coating Denver Colorado