Have to agree with most people here. I am no expert and my opinion is strickly based on my personal research. However, closed cell spray foam is the $#!t.
Everything I have read tells me that the R value system is flawed in that testing is done in controlled environments with no air movement and low humidity (read low moisture). Batts will allow air movement through them (hold one up to a fan and feel the air go through it). They are meant to control the difference in temperature between sides. Closed cell foam on the other hand controls not only temperature but air movement as well.
Cowboy, I am a fan of Holmes so I can see why your cutomers wanted spray foam.
This summer I am going to tackle my problomatic catherdral ceiling and metal roof with spray foam for not only a better insulating value and vapour barrier (closed cell is rated at an R value of 6 per inch in most applications which I think is under rated) but also to alleviate the issue with moisture due to the metal roof. When the air condenses under the metal the water drips onto the insulation and over a number of years makes it virtually useless. Batts are like a spnge, they never give up the water they take in. Damp batts have an R value of "R totally useless."
The plan is to carefully remove the metal roof (I plan to reinstal it after), remove the batts and have the entire roof spray foamed 6 inches deep. I will then put the metal roof back on and hopefully never have huge ice damns again and drop my heating bill significantly. I am expecting serious savings and a pay back of about 6 years on the cost of the spray foam. I am even considering having an entire wall done since I am goind to have the siding off that side for an unrelated project. This house was built with ballon framing (not sure what it is called in other places). The walls were built first and then the floor is built inside of it. A stupid design and I am not sure why anyone would use it. What this means is that the portion of the wall that goes below the floor has no vapour barrier unless someone was smart enough to put it up before the floor. Which in this case they were not. The means that my floors and lower part of the wall feel cold in the winter. No batt insulation can fix this. The only thing to do is spray foam the bottom part or use rigid insulation with some kind of sealant. However the spray foam will seal best. Eventually when I change the siding I will have all the bottom portions spray foamed. I did it from the inside in the bathroom when I renovated and it made a huge difference in that room.
