Use minimal expansion foam sealant around windows and doors

ask the expert
Do you have a question about your home? Gettum Associates Inc, Indianapolis home remodel experts offer the opportunity to ask your question and receive and answer from one of our experts. You can submit your question here

Spray foam insulation around a window frame

Recent email sent to the Indianapolis Home Experts: Last fall, we replaced our old windows, and when placing the new ones, we sprayed a foam insulation between the frames and the windows. Now, this spring we tried to open the windows to find out that they will not open because the foam expanded too much again the windows. Any idea, how can we fix this problem? The window casings have not yet been placed so that could be a plus, not sure though. Any suggestion would be appreciated. Thanks! – Raymond spray foam insulation Reply: Hi Raymond, thank you for your question.  You had the right idea when installing spray foam between the framing and window. Spray foam is excellent at sealing gaps in this type of installation. Sorry to hear about your trouble. Unfortunately, it sounds like you may have chosen the wrong type of spray foam insulation. We see this happen when homeowner’s install regular expanding foam sealant and not the “minimal expanding” type of foam sealant that is recommended for windows and doors. What happens is when normal spray foam expands, it can “push” the window jambs and sills out of plumb or level and cause the window to become hard to open or in some cases not allow it to open at all. The minimal expansion sealant, on the other hand, does not expand as much or as rapidly, yet will still fill all the gaps and insulate between the rough house framing and your window frame. But dont be worried, with a little time and effort you can usually fix this. Here is what you need to do: Remove the interior trim casing around the window if you have not already done so. Start by scoring the foam with a utility knife on all four sides around the window, or wherever the foam is installed. Then, you can dig or scrape the foam out of the opening. This may take a while depending on the size of the gap between the framing and the windows. After you have completely removed the foam, you need to be sure to get the window frames and jambs back to level or plumb. Place a level along the window sill and side jambs to see how much the window will need to be adjusted.  Place wood shims between the rough-framing and the window frame in the area of where you will install new nails or screws.  This will help keep the window frame square, plumb and level.  Install new fasteners as necessary. Then, cut off the shims flush with the window frame. Finally, fill the void between the rough framing and window frames with minimal expanding spray foam insulation, normally labeled specifically for use around windows and doors.  Follow the directions on the can and if some of the foam expands beyond the frame, you can trim with a utility knife. When the insulation has cured, you can reinstall the casing. Voila! Problem solved! If you have any other questions, please do not hesitate to contact us. We can be reached at [dynamic_phone] or visit our website at If you have questions or need advice for your home, feel free to “Email the Expert

Recent Posts

Skip to content