A few weeks ago, I received one of those calls I fear most: an issue with a spray foam job.

I have a contractor in Northern Vermont whom I deal with, and he had bid a new house on a small lake in his area. He explained to the customer the benefits of closed-cell foam and the vapor retardant properties inherent to the product. The homeowner seemed very receptive and verbally awarded him the job. It was about $30,000.

George Spanos is the President of Spray Foam Distributors of New England, and started his business almost 10 years ago as a spray foam contractor. With service throughout New England and beyond, Spray Foam Distributors of New England is the largest and most technically qualified supplier of SPF material, equipment, and training in the Northeast. The company is a Top-20 Graco distributor and a leading supplier of spray foam insulation and roofing materials from Bayer Material Science and others.

The contractor called the homeowner several times to schedule the job and the homeowner kept putting him off–next week… next week. One day the contractor called and the homeowner told him that he went with a cheaper bid. Come to find out later there was a Rhode Island spray foam contractor whose family , also had a house on the lake. One weekend while at the lake, the Rhode Island contractor stopped into the house under construction to give a bid.

He explained to the homeowner that he could save him some money by doing a combination of open-cell and closed cell foam. In the walls, he wanted to put 1 to 1.5 inches of closed-cell foam and then 3.5 inches of open-cell foam, and in the roof 1.5 to 2 inches of closed-cell and 9 inches , of open-cell on top. I think that the price was about $20,000; a savings of $10,000 seemed like a great idea to the homeowner at the time.

Fast-forward a month: the hybrid foam system was done. They were effortlessly holding heat in the building and moving forward with construction. They had been waiting to pour the concrete slab in the basement until the insulation was done so that the concrete wouldn’t freeze. Once they poured the concrete in the basement, they turned up the heat, as it was exceptionally cold outside; below zero.
Well, all of that moisture coming out of the slab basically turned the house into a tropical rainforest. There was a huge temporary vapor drive created, and that moisture forced its way right through the open-cell foam. Once it hit the surface of the closed-cell foam, it condensed and the water permeated back through the open-cell foam in many places. Compounding the issue was the fact that the homeowner insisted on installing proper vents to the underside of the roof and spraying the closed-cell to them. There were several spots where there was less than 2 inches of closed-cell foam.

This puzzled the homeowner and he called the original contractor from Northern Vermont and then called me to find out what was going on. I explained to him that 2 inches of closed-cell foam was not enough to keep the surface of the closed-cell foam above the dew point with 9 inches of -cell foam on top when it is below open zero outside. He asked why the Rhode Island contractor didn’t know this, so I spoke with him afterward. He was also puzzled, as he had done this combination several times in Rhode Island.

Now I’m no building scientist, but I know that there is enough climate difference to understand that what could work in Rhode Island doesn’t necessarily work in Northern Vermont. Unfortunately, the homeowner was very impatient and didn’t give the Rhode Island contractor the opportunity to even look at the job and what was going on, never mind the opportunity to make it right. He hired the original contractor to remove all of the open-cell foam and re- the whole open house with the originally spray specified amount of closed-cell foam.

I didn’t ask the original contractor how much he was charging, but I bet it was more than the original quote–an unfortunate and expensive lesson. For the homeowner, his lesson was cheaper is not always better. For the contractor, be careful in specifying a hybrid system, because what works in one climate zone doesn’t necessarily work in another. If you are going to go with a combination of open-cell and closed-cell, err on the side of caution.