Insulation can play many essential roles in a home or business, with everything from temperature control to energy savings to noise reduction being counted among its benefits. Spray foam insulation is one of the best insulation options available, and it can be applied in a range of places, including around ductwork.
With that in mind, we’ve created this guide to give you the key facts on applying spray foam insulation around ducts so you can be prepared for future contracting jobs.
So You Can Apply Spray Foam to Ductwork?
Spray foam is known for its diverse application possibilities and ability to readily cling to surfaces and materials, with ducts and the areas around them being just one of these possibilities.
Using spray foam on ductwork can help you to:
- Insulate the ducts and create an airtight seal that will ward off drafts, moisture, and pests
- Fill any gaps and cracks in the area, which in turn reduces air leakage and optimizes airflow, which is vital since homes can lose 20% to 30% of their air through leaky ducts
- Improve a customer’s HVAC efficiency and lower their energy bills, as sealing ducts can reduce costs by 5% to 30% per year
- Keep condensation from forming by preventing “sweating” by the ducts
However, you will want to be sure to use closed-cell spray foam rather than open-cell spray foam. Though cheaper, open-cell foam is lighter and porous, so moisture is able to penetrate it which could lead to later problems. Closed-cell foam, with its denser structure, completely blocks out air and moisture, providing a more rigid and reliable result. Only 1 inch of hardened closed-cell spray foam is needed to meet insulation standards.
Of course, when working with ductwork insulation on-site, you will want to wear protective gear like gloves, goggles, and masks during the spray foam application process.
Surface Preparation When Using Spray Foam Around Ductwork
Before you begin insulating the spaces around your ducts with spray foam, you will want to take some steps to ensure your project goes off without a hitch.
- First, make sure to clean the ducts themselves and any surrounding areas prior to spray foam application. Dirty ducts and other surfaces can interfere with proper spray foam adhesion, so it is vital to make sure any surface you are working with has been well cleared.
- Carefully seal all joints and cracks in the ductwork to prevent any leakage. While spray foam is an excellent insulator, you wouldn’t want it seeping into a customer’s ducts and potentially damaging them or reducing their operational abilities.
- Make sure you do not apply the foam in extreme temperatures, as 60 °F to 90 °F is the recommended temperature range for ambient air and surfaces during a spray foam project. Applying only within this temperature range allows for the effective expansion, curing, adhesion, and bonding of your spray foam material.
- Ensure you are working in a well-ventilated area, using fans and other equipment to promote airflow. This, along with protective breathing gear, will allow you to avoid the dangers posed by toxic fumes.
Application Tips for Spray Foam
Once you have thoroughly prepared the area and your materials, you can begin applying your spray foam. Here are some core spray foam application techniques:
- Be sure to apply the foam uniformly across the surface, and don’t neglect any corners or joints
- You’ll want to make multiple light coats rather than a single, thick layer, as lighter coats allow for the proper expansion and curing of the foam
- Shoot for an application thickness of about 1/3”
Where to Avoid Spray Foam
Some spaces should be kept clear of foam, so be careful when applying spray foam insulation around ductwork. Avoid the following:
- Areas that receive a lot of moisture
- Areas that feature electrical wiring or components
- Attics that lack proper ventilation
- Areas around complex HVAC equipment
- Areas around plumbing fixtures
For electrical wiring and HVAC equipment, improper use of spray foam could lead to electrical shorts or fire hazards. Plumbing fixtures, meanwhile, like pipes, can often expand and contract, so separation layers are often needed to account for this variability.
FAQs for Using Spray Foam Around Ducts
While the core information above should serve as a solid guide during your project, you might have some additional questions as you proceed, so here are some common ones we receive and our answers.
What are some potential problems with spraying ductwork?
While the benefits far outweigh the risks, spray foam can pose some issues for ductwork if it is not applied properly. Partial application can lead to condensation issues, and the hardened spray foam can lead to ducts being less accessible to correct such problems.
Are there any compliance requirements?
Compliance and approval processes needed for applying spray foam insulation around ductwork can differ depending on state and local municipality regulations. Be sure to check in your area about any compliance requirements prior to application, as removal and replacement can be costly in the case of incorrect or inadmissible application.
How do I calculate my spray foam needs?
When determining your spray foam requirements, you will want to take into account all dimensions of the ducts you will be working with along with the accompanying space surrounding them.
You will need to establish the board-feet needed for the spray foam, which equates to one squared foot at one inch thick. Reach out to our team and we can assist you with further calculations.
Need Spray Foam and Equipment? Contact Us!
SprayWorks Equipment supplies effective and reliable spray foam and equipment that can help you apply foam insulation around ductwork and in other essential spaces. Our products include:
Additionally, if your team needs assistance with spray foam application, we provide numerous spray foam training options, including our spray foam and coatings school, on-site spray foam training, and online spray foam training.
To inquire about any of these training programs or to ask us about any of our products ideal for applying spray foam around ducts, contact our team. We look forward to assisting you!
