Insulating Your Garage

It’s almost winter and we are already beginning to feel the cold settle in here in New England. Now is the perfect time to start insulating your house before the real winter cold fronts start to hit. In this four part series, we will take a look at the most common places you suffer heat loss in your home. This blog will take a look at the best ways to insulate your Garage for this upcoming winter, just make sure to get a garage door repair so you are sure it’ll work. 

Your garage is most likely used for one of three things; A place to park your car, a storage room, or a workshop. In any of these cases, an uninsulated garage can cause you to lose a huge amount of heat and money, and nobody wants that, so make sure you get a garage door repair if need for a properly insulated garage. There are a few very simple ways to help in this area (and one way thats a bit more involved) that will help give you a warm work space, parking space, or storage space this winter. Let’s take a look!


This part is simple, just read our other blogs here!

Windows – Click Here!
Doors – Click Here!

Once your done with these steps move onto step 2.


Garage door weather stipping

Properly installed garage door weather stripping

The next thing you are going to want to do is get weatherstripping for the side, and top, of your garage door. The first step is to get the measurements for the top and side trim and prepare your weather strips to be cut to size. Place the top strip on first, with the vinyl sweep against the door itself. It’s recommended you have a helper to hold the weather strip up for you while doing this. Most strips will screw into place, with small divots to indicate where to screw in the strip. A power drill will make this process fly by.

Next you’re going to want to screw in the two side strips. This will be almost the same as the top with one caveat; when you place the weather strip flush up against the trim and look at how it interacts with the strip you just put on, we’re going to have to make a curved cut on the top side to help it to fit snug. This will be the same concept for most weather strips and can be free handed without worrying too much about it. It’s better to undercut here than overcut, as overcutting can lead to gaps which will leak in cold air.

After you’ve installed the strips, get your caulk gun and apply a thin bead along the outside edge of each new weather strip. If there is a gap where two weather strips meet, caulk that over as well.


type-chartThere are two main types of strips that fit on the bottom of a garage door; screw in and slide in.

Screw In – These are the easiest to remove and replace. Simply open the garage door to head level and remove any screws or nails from the existing strip and discard it. Measure the length of the underside of the door and cut a piece of weatherstripping to length. You may need to use a full size strip and part of a second one depending on the brand and length of your garage door. Screw in the new strip and inspect the sides. If the outward hanging vinyl on the bottom is grinding against the side weatherstripping, cut it down to avoid the friction ruining both.

Slide In – Open to door to head height and take a look at the existing track. Chances are the track has been hammered in to prevent the weather strip from sliding. If this is the case take a flat head screwdriver and pry the track up enough to allow the old strip to slide out. If you’re having a hard time with the strip jamming cut the strip in half and remove each half individually. When placing in the new track, hold the new strip in a deep “U” shape as you slowly slide the new strip into the track. You can bend the ends of the track back to help seal the new strip into place.


The next largest amount of heat loss will occur through the walls in your garage. For this we’re going to need a lot of faced insulation batts. To get started you will need to find the height and width of the joist cavities (the space in between wall / ceiling joists). Purchase batts at size if possible, or slightly larger to cut down. Try to avoid getting batts that are too small and need to be stacked, as this creates more opportunity for air leaks to form.

Wall Insulation
When installing insulation batts, begin by sweeping out the joist cavities and laying your batts out around the room. This is easier than running back and forth to grab batts for each cavity. Place the unfaced (paperless) side of the batt into the cavity flush against the top joist. Gently press the batt into the joist cavity, being careful not to compress the insulation material. Tuck the flanges (the excess paper) very gently into the cavity so that there is no paper extending past the joist. Once this is in place, staples the flanges to the joist at 8″ intervals on both sides.

You may run into pipes, air ducts, and wires while doing this. If this is the case just tuck the batt behind the fixture and proceed like normal. You may also run into a cavity that is a different size (or shape) than the rest. If this happens hold your batt up to the cavity and use a hand blade to cut the batt into the proper size or shape.

Ceiling Insulation
For the ceiling, you’re going to add a step before getting the insulation batts in place by installing baffles. Baffles are designed to keep air flowing behind the insulation through the soffits leading outside and the ridge vent. Blocking air flow from soffit vents by covering them with insulation is a very common mistake. Maintaining proper cool air flow against the roof will prevent ice dams (outside) and condensation (inside) from forming. Measure the length and width of the ceiling joist cavities and find the right sized baffle. If you can’t find one the proper size it’s okay to cut down baffles to the correct size. If using cardboard or plastic baffles, score them with a blade and then fold them over to create a nice clean cut edge.

Staple the baffle in the joist cavities to the ceiling at regular 8″ intervals and then install your insulation like normal. It’s that easy!


There you have it! A nice warm and inviting space that you can use however you want this winter without fear of freezing! Stay tuned for our next edition for insulating your home, where we will talk about attics. The attic can be responsible for up to 25% of all heat lost throughout your home. It’s not as easy to insulate as the rest of the house, but can definitely save you some serious cash this year!

Thank you for tuning into this blog. If you have any further questions or want to know more about this subject, feel free to reach out to us online at http://koopmanlumber.com, or click below to share this blog and navigate over to our facebook page!

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