Replacing fogged or broken windows doesn’t have to be a pain in the glass
If you own a motorhome long enough you may eventually be faced with circumstances that require you to replace a dual-pane window. A large motorhome has a lot of windows and that means a lot of opportunity for a broken window or a window that is fogged internally from condensation. Not every fogged window needs a complete replacement but in many cases replacing one or two smaller windows may be less expensive than driving to a service center to have the glass removed, cleaned and reinstalled.
Our Tiffin coach is 8 years old and during that time we have not had any broken glass but we have had a few windows fog internally. Each time we have considered taking the motorhome to a service center for a repair, but once we factored in the travel time, fuel cost, time away from home, etc., a DIY replacement has always been our choice, as it was this time as well.
No matter what size window you have, the replacement route is a straightforward process, but of course the difficulty increases in proportion to the size of the window. The window we replaced for this article is the driver’s-side window and in this coach it is approximately 48 inches wide, which means it is also fairly heavy and difficult to ship. We ordered our replacement from the Tiffin factory and in less than two weeks the window showed up in a huge box, which required a delivery truck with a lift gate to unload.
After seeing the size of the box, we instantly questioned the decision to tackle this as a DIY project. However, after opening up the box, we realized that more than a foot on each end of the box was foam insulation to protect the glass during shipment. After breathing a sigh of relief we scheduled a helper so that two physically able individuals would be there for the installation.
Every manufacturer constructs and installs its windows in a different manner, so make sure you double-check yours before you begin so you can plan ahead with supplies such as foam insulation tape, rubber weatherstripping and exterior sealant. We picked up the needed foam tape, sealant and weatherstripping at a local home-improvement store. The flange on this window allowed for a 9/16-inch-wide rubber seal so that is what we used. The foam tape on the inside trim was ¾-inch wide so we picked up two rolls of that also. Perhaps the most important supply item you will need is the sealant/caulk. We used a 100 percent exterior silicone caulk that remains flexible after curing and doesn’t shrink. Make sure you do not use self-leveling sealants as used on roof repairs because it will sag when used on a vertical application such as this project. Also make sure your tube of sealant has not expired, because many of the new caulks now have an expiration date.
For this job you will need some basic tools such as a cordless drill with the correct bit for your window screws, a razor utility knife, a rubber mallet and possibly a small 90-degree driver with a bit insert. We needed a 90-degree wrench because one of the window screws was at the edge of the dash and access with a cordless drill was impossible. We also needed two ladders with enough reach to allow easy access to the height of the window from outside of the motorhome.
Even with time to take photos along the way we were able to remove the old window and install the new one and seal the edge in about 2½ hours. In terms of the number of steps required to complete the job, it is a simple project. It’s the size of the window that adds to the difficulty, and though we got by with two experienced people, in hindsight, three would have been better. Three people allows you to have two people outside ready to hold the window as it comes out and one on the inside pushing.
Take a look at the step by step video so you can decide if you want to tackle the job yourself or leave it to the professionals.