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Carroll, IA(712) 792-3080
Des Moines, IA(515) 283-3802

residential spray foam insulation services for new construction residential spray foam insulation services for new construction

Common Questions About Spray Foam Insulation and Roof Coatings

Click on any of the questions below to see our answer and more information.

What does it cost per square foot?

We don’t price per square foot. The reasons we don’t are because we could give you a low square foot price like our competitors and then add in a trip charge, prep charge, clean up charge, fuel surcharge etc. We don’t do that, we give you a total completed price. What you really want to know is what the job is going to cost total. To give you an idea per square foot price, foam starts around $1.25 and goes up from there depending on what kind of foam, how thick, job size and job location, etc. This is why we want to give you a free estimate so you will know what the actual total cost is, no hidden cost later on.

How does it compare in R-Value to Fiberglass or cellulose?

Spray foam can be from an R-3.8 to 4.5 for open cell foam and  R-7 per inch on closed cell foam, depending on manufactures. R value is not necessarily the best way to judge performance of insulation. Air sealing is more important. Fiberglass and cellulose both lose insulating value when air is passed over or through them, up to 47% of their labeled R factor. Fiberglass batts when poorly installed can lose up to 28% of their labeled R factor.  These are numbers from Oak Ridge National
Laboratories where scientist were installing them, not low paid labors.

How clean does the surface have to be to make spray foam stick to it?

There can be no oil, grease, water or excessive dirt on the surface. Most pole barns are clean enough unless they have had livestock in them.

How do you trim the spray foam?

For open cell foam we use a long serrated blade that looks like a recipacating saw blade. For closed cell we have a specialized grinder to take it off. We try avoiding trimming closed cell foam because it is labor intensive and expensive.

Does foam add structural strength to the building?

Closed cell foam will add some racking strength to the building. Foam is not designed to be a structural building material. If you are relying on spray foam insulation to hold your building together, you have other problems that need to be addressed with that foam cannot fix.

Will spray foam stick to the underside of the roof?

Yes, it will stick to the underside of the roof without any fasteners or supports.

How much will spray foam save me?

That depends on a lot of different factors, such as building design, HVAC usage, etc. Industry experts will tell you up to 50%. What you can expect is to be more comfortable in your building.

Which is better, closed cell or open cell spray foam?

Both work well. It really depends on your application. Closed cell works better below grade or in harsh conditions like livestock buildings. Open cell is a better cost per R-Value and is the best choice for sound control. Give us a call and let our highly trained professionals help you make the best decision for your application.

Do rodents eat spray foam?

There is no food value to spray foam. With that being said, rodents will eat just about anything. Spray foam stops air leakage and heat loss. If rodents can’t smell or feel the heat on the other side of the wall, they are less likely to want to get in.

Can I install spray foam myself?

No. It takes expensive specialized equipment and highly trained professionals. This is really a process best left up to professionals.

Do I still need a Vapor Barrier?

With open cell foam, it is required by code. Closed cell foam, depending on brand and thickness, no. Code has not kept up with modern building science.

Do I still need house wrap?

Foam is an air seal. You don’t really need house wrap for an air seal. We do still recommend house wrap, it is a great drainage plane, when installed correctly.

Won’t spray foam make my house too tight? Houses need to breathe.

Build them tight, ventilate them right. Most houses are not too tight, windows and doors leak plenty of air. We do recommend installing Air to Air exchangers properly calculated by a professional. Rely on building science not “old wife’s tales” or “urban legends”. Remember, houses don’t have lungs!

Why should I choose Iowa Spray Foam over another company whose price is much lower?

You get what you pay for. Many contractors shoot a low price and then add on prep, clean up or trip charges not included in their estimates. They won’t have the proper liability or workman’s comp insurance leaving you exposed in an accident. Iowa Spray Foam invests heavily in training, safety and equipment in turn providing  quality jobs for its employees. What this means to you is the job done right the first time by a professional.

I have gotten several estimates, but the price is all over the board. How do I make sense of these?

What you should be looking for is a detailed quote including estimated R- Values, total depth, type and brand of foam and a plain explanation of areas to be sprayed. If the “Lowest Price” is too good to be true, it is probably missing something.

Doesn’t spraying foam on the underside of the roof will void the warranty on the shingles?

Most shingle manufactures will not void the warranty. However, some, like Owens Corning who only make fiber glass insulation, roof vents and soffit material void warranties in this case. Go figure on this one! The other thing I will ask you, have you ever know someone who collected on a roof warranty? Very few.

Isn’t spray foam a fire hazard?

No. Most spray foams area a Class 1 Spray Foam. They have a better smoke development, flame spread numbers and auto ignition points than wood.

Can I leave spray foam exposed?

In most cases, no. Code requires most insulations to be covered with an approved thermal barrier. Call for details on your project or consult your building inspector.