At the most basic level, entry and garage doors serve a simple but effective purpose: keep the outside out and the inside in. On a higher level, there is a lot more that goes into their design. Certifications, safety standards and energy codes must be met to produce a product that’s ready for sale.
When it comes to insulating doors and garage door panels, manufacturers have two primary options to choose from: expanded polystyrene (EPS) and polyurethane (PU) foam.
In most instances, a manufacturer will utilize an insulation product simply because it’s what they’ve always used. It’s an easy mindset to get stuck in, but when there is an opportunity to improve operational processes while ensuring the quality of your product, one type of insulation is the clear choice.
An efficient material
Optimizing manufacturing methods requires time and precision. When you work with an efficient material like polyurethane to insulate entrance and garage doors, you’re working with a material that can accomplish the same job as EPS, but in fewer steps.
“To be frank, you can make more doors in less time with PU as opposed to EPS,” said James Lutz, Technical Services Representative at BASF. “A major advantage is that polyurethane foam adheres itself to the substrate whereas EPS has to be glued in with adhesive.”
While glue is a necessary expense to ensure proper adhesion of EPS to the substrate of a door, it’s an expense you can avoid with polyurethane foam insulation. Polyurethane insulation bonds to the surface as part of the application, ultimately eliminating a manufacturing step.
EPS foam also comes with the challenge of ensuring the insulation fits the cavity of the door properly. This is something that takes time and effort, and unfortunately generates waste material.
“Working with a flush door makes cutting EPS relatively easy, no denying that. But, when you’re working with doors that are two-panel, six-panel or even 12-panel, you have to cut the EPS to fit the shape of the door and you’re going to end up with wasted material."
A streamlined manufacturing process
If you use EPS to insulate entry and garage doors, it’s important to ask yourself a simple question: How much square footage of your plant is dedicated to warehousing EPS? Considering how EPS insulation is made or received from a molder, it’s probably a lot. This is valuable floor space that could be dedicated to manufacturing more doors, helping you to grow your business.
“When you use EPS to insulate your doors, you’ve really got two options. First, you expand the insulation yourself, and that’s a long and drawn-out process involving pre-expanding the foam beads followed by a two to five-day aging process. Once aged, you then take those beads and put them in a big expander and form giant blocks as big as 25 feet long by six feet wide by four feet thick.
“Once you’ve extracted that block of foam from your expander, you have to let it age for seven days to allow the EPS to shrink to its final dimensions. Where do you leave those blocks to age? On valuable floor space. If you move to PU, you can free up space in your plant because PU takes up far less space,” said Lutz.
The other option, according to Lutz, is to buy your EPS from a molder, but there are additional factors to consider. First and foremost, how close is this molder to your plant? What if the only one available to you is a couple of states away? Then you need to consider transportation and shipping costs. Sure, EPS is lightweight, but you can only fit a few pounds into a single trailer. When you’re paying for the cost per mile to ship, that can add up.
With a smaller storage footprint, polyurethane foam insulation will reduce lead times and create a leaner operation that requires less storage of insulation material which can ultimately result in the opportunity to take your manufacturing output to the next level.
A more durable door
While polyurethane foam is prime for entryway door insulation, it’s ideal when it comes to garage doors. For BASF Senior Scientist, Megan Szyndler, PhD, choosing polyurethane over EPS isn’t a debate.
“Polyurethane insulation is the better product for some obvious reasons,” said Szyndler. “The initial R-value is great and much like in insulating entry doors, PU easily takes the form of the substrate, filling every crack and void with excellent substrate adhesion.”
The kind of simplicity that polyurethane insulation can bring to garage door manufacturing is more than just filling the cavity of a garage door panel. Using polyurethane to insulate your garage doors has a positive impact on the whole design of a garage door.
“When using polyurethane in garage doors, you’re able to address the issue of sound deadening. Because polyurethane adheres so well to the substrate, you aren’t getting a lot of rattling when the doors move up and down resulting in a much sturdier product,” says Szyndler.
To further that point, the rattling of garage doors can have a detrimental impact on EPS if it’s not adhered correctly to the garage door substrate. Prolonged use means continuous rattling and EPS insulation can not only come loose but also get ground up, compromising a garage door’s structural, insulation and sound deadening properties. Polyurethane takes potential human error out of the equation, solidifying the performance and confidence of your product.
“Ultimately, you have a better product with PU insulation compared to EPS insulation,” said Szyndler.
At BASF, we create chemistry for a sustainable future. With over 150 years of experience, we know how to help our customers find the right solutions for their needs and applications. For more information on doors, contact pmconstruction@basf.com.