A homeowner in Hall County gets a spray foam quote. The price is higher than fiberglass. She hesitates, then decides to go with the cheaper option instead.
Two summers later, her energy bills are still sky-high. Her HVAC runs almost constantly in July. And the contractor she calls tells her the fiberglass in her attic has absorbed moisture and needs to be replaced.
She ends up spending more than the spray foam installation would have cost in the first place.
This happens more than you’d think. And in most cases, it starts with a myth.
There’s a lot of misinformation floating around about spray foam. Some of it comes from well-meaning neighbors. Some of it comes from contractors who don’t offer it. And some of it just sounds convincing enough that people don’t question it.
Here are six of the most common myths, and what’s actually true.
Myth 1: Spray Foam Installation Is Just Too Expensive
This is the one we hear most often. And it’s understandable. The upfront cost of spray foam is higher than fiberglass batts. That part is true.
But the full cost picture looks very different.
Spray foam creates both a thermal barrier and an air seal in a single installation. Fiberglass only provides thermal resistance. It does nothing to stop air from moving through gaps, cracks, and penetrations. In a home in Flowery Branch, GA, where summer heat and humidity push aggressively through every opening, that difference shows up directly on your utility bill.
The U.S. Department of Energy estimates that air leakage accounts for 25 to 40 percent of the energy used for heating and cooling in a typical home. Spray foam addresses that problem. Fiberglass doesn’t.
Most homeowners who switch to spray foam see meaningful reductions in monthly energy costs. When you factor those savings over five to ten years, spray foam often costs less than cheaper alternatives, not more.
Myth 2: Spray Foam Makes Your Home Impossible to Resell
Some homeowners worry that spray foam is a red flag for future buyers. The reality is the opposite.
Buyers and home inspectors look favorably at spray foam. It signals that the home has been upgraded with a high-performance insulation system. It also means lower energy costs, better indoor air quality, and a tighter building envelope, all of which are selling points, not liabilities.
What actually creates problems at resale is improperly installed spray foam. If the wrong product was used, if it was applied at the wrong thickness, or if it wasn’t installed by an experienced contractor, it can cause issues that show up during inspection.
So the myth isn’t entirely baseless. Bad spray foam installation can cause problems. But properly installed spray foam by a qualified contractor is an asset, not a liability. It’s one more reason why the contractor you choose matters as much as the product itself.
Myth 3: Spray Foam Is Only for New Construction
This is one of the most common misconceptions, and it keeps a lot of existing homeowners from getting the performance upgrade their home actually needs.
Spray foam works extremely well in existing homes. In fact, some of the biggest gains come from retrofitting older homes that have been leaking conditioned air for years.
The most common retrofit applications in Flowery Branch include:
- Attic floors and rafters, where heat gain in summer is most severe
- Crawl spaces, where moisture infiltration from the ground drives humidity into the living space above
- Rim joists, which are almost always uninsulated or poorly insulated in older homes
- Exterior wall cavities, which can be accessed through small bore holes without major renovation
- Garage ceilings, especially when rooms above the garage have temperature problems
None of these applications require new construction. They can all be done in an existing home with minimal disruption to daily life.
Myth 4: Your Home Won’t Be Able to Breathe After Spray Foam Installation
This is the myth that sounds the most scientific, which is probably why it sticks around.
The concern goes something like this: if you seal the home too tightly, moisture and stale air have nowhere to go, leading to condensation, mold, and poor indoor air quality.
Here’s the important distinction. Uncontrolled air leakage is not the same as ventilation. Random gaps and cracks in your building envelope don’t provide healthy fresh air. They bring in hot, humid, unfiltered outdoor air in summer and cold drafts in winter. That’s not beneficial air exchange. It’s just energy loss with extra humidity.
A properly insulated and sealed home still has controlled ventilation through your HVAC system. In some cases, an energy recovery ventilator is added to provide fresh air exchange without the energy penalty. That’s a planned, controlled system, and it performs far better than relying on random air leakage.
Modern building science has moved firmly away from the idea that homes need to be leaky to be healthy. The goal is to build tight and ventilate right. Spray foam installation is a core part of achieving that.
Myth 5: Spray Foam Smells Bad and Never Goes Away
This one has a grain of truth to it, and it’s worth addressing honestly.
During and immediately after spray foam installation, there is an odor. It comes from the chemical reaction as the two components mix and expand. That’s normal.
However, the odor dissipates as the foam cures. For open-cell foam, that typically takes 24 hours with proper ventilation. For closed-cell foam, it’s usually faster. After the curing period, there is no ongoing smell.
The key phrase here is proper ventilation during installation. A qualified spray foam contractor will ensure the space is adequately ventilated during and after the job. Occupants are typically asked to stay out of the treated area for a set period, usually a day or less depending on the space and product used.
Homeowners who report persistent odor problems after spray foam installation almost always had the work done by an inexperienced contractor who used incorrect mixing ratios or applied the product in conditions that weren’t suitable. The problem isn’t the product. It’s the installation.
This is another reason why choosing the right contractor matters enormously.
Myth 6: All Spray Foam Products Are the Same
Walk into any conversation about spray foam and you’ll hear open-cell and closed-cell mentioned. Many homeowners assume they’re interchangeable. They’re not.
Open-cell spray foam is lighter, more flexible, and less expensive per board foot. It has a lower R-value per inch, typically around R-3.5 to R-4, and it’s permeable to moisture vapor. It works well in interior applications like attic floors and interior walls where vapor permeability is acceptable.
Closed-cell spray foam is denser, more rigid, and has a higher R-value per inch, typically R-6 to R-7. It acts as both an insulator and a vapor barrier. It’s the better choice for crawl spaces, rim joists, and any location where moisture is a concern, which in Flowery Branch’s humid climate is almost everywhere.
Using the wrong product in the wrong location doesn’t just reduce performance. It can create moisture problems that cost more to fix than the original installation.
A good spray foam contractor assesses your specific home, explains the difference between the two products, and recommends the right one for each area. If you get a quote that doesn’t distinguish between open and closed cell, ask why.
Ready to Find Out What Spray Foam Can Actually Do for Your Home?
The best way to move past the myths is to get real answers based on your specific home and situation.
The team at HD Roofing and Spray Foam is ready to help. Contact us today to schedule a spray foam installation assessment in Flowery Branch, GA and get a straight answer on what your home needs, what it will cost, and what you can expect in return.