Insulate Your Garage Door

If you have an attached garage, and especially if you have living space above your garage, make sure that your garage door is properly insulated. When we moved into our house we had a crappy, uninsulated metal garage door, and we ended up having a terrible time controlling the temperature in the bedroom above our garage. It was too hot in the summer and too cold in the winter. But I insulated the garage door this past winter, and that’s all behind us now.

The garage was decidely warmer all winter long, as was the room above it. Likewise, we’ve had much better temperature control this summer. While this is undoubtedly reducing our energy bills, the best thing about it is that it makes our house more comfortable/livable.

So how did I do it? While there are garage door insulation kits available for sale, I couldn’t find any at our local stores when I went out looking. Thus, I simply bought foam sheathing at Home Depot and cut it to fit in the garage door panels. The ‘pocket’ in the door panels is just over 1.5 inches deep, so I used a double layer of 3/4 inch sheathing, which I tucked behind the metal lip that runs around each panel. I then secured it all in place with aluminum foil tape — I considered using Liquid Nails, but wanted to be able to take it down if it didn’t work as I had hoped. And while I was at it, I also insulated our water heater (which is located in our garage) with a water heater blanket.

Note: A few words of caution… First of all, as several commenters have pointed out, you might need to re-balance your garage door due to the added weight. Unless you really know what you’re doing, this is best left to a professional. Also, foam board is flammable, and not meant to be exposed. Thus, there is some risk in using the method outlined above instead of a “real” garage door insulation kit.

55 Responses to “Insulate Your Garage Door”

  1. Anonymous

    May I simply just say what a comfort to find someone who really understands what they’re
    talking about on the net. You certainly realize how to bring a problem to light and make it important.
    More people must check this out and understand this
    side of the story. I was surprised you are not more popular since you surely have the gift.

  2. Anonymous

    Right now it looks like Drupal is the top blogging platform out there right now.
    (from what I’ve read) Is that what you are using on your blog?

  3. Anonymous

    However, my big reservation about moving forward with this project, is that the ceiling and all walls but one, are exposed to wind blown outdoor temperatures. Since the builders never even insulated our living space floors from the ground, I’m almost sure the garage is totally uninsulated. So I fear, rather than being an inexpensive “cherry on top” kinda project, this may be a first step in a large, expensive series of insulating projects. Theoretically I could spend $300 and build an R-26 rated wall where the door is, but that wouldn’t fix the insulation shortcomings by more than a couple degrees. I need to weigh the situation better here, including the adjacent walls and ceiling. The cold concrete floor has interlocking rubber-foam matting on it.

  4. Anonymous

    Excellent ideas presented here. I have an uninsulated, attached garage I use primarily as a workshop/ hobby room for hours at a time daily. In Alabama, outdoor temps often drop below 20 at night in the winter, and rise above 100 during the warmer summer days. The garage would often be like a refrigerator in the winter, and a sauna in the summer, for days at a time.
    I elected to price out and select two insulation methods for our 16’x7′ two car garage door which is fabricated out of foam panels and aluminum bracing, and powered by a 1/3 hp motorized opener.
    There are (16) panels, each 21″ x 45″, with about 1″ clear behind the bracing channels.
    First idea involved limiting weight and cost. I opted to use 3/16″ bubble wrap sandwiched between heavy duty aluminum foil (the kitchen variety), combined with 3/4″ polyurethane foam, and held together with 3M spray-on contact adhesive (3M Super 77). Foil tape would hold the panels in place inside the channel bracing. Pricing this up, I found this could be done for about $120+tax, and likely 12 hours of uninterupted labor.
    Second method involved the same idea, the only difference being substitution of the homemade foil bubble wrap for pre-made foil duct wrap. Last night at Home Depot, I found this product, sku #363984 Insulated Duct Wrap R-6. It is foil backed fiberglass wrap, about 3/8″ thick, 2′ x 30′ for $35. One package would cover a single bay door, and two would cover a two car garage door. The drawback is the weight and cost, but the fire combustion characteristics and the hours saved from making your own foil wrap, justify the additional $25 bucks. Total cost of this method is $145 plus tax. I’d estimate the R value to be in the R-10 to R-12 range.

  5. Anonymous

    Hey KC,
    I got to thinking after I replied, you might check a hobby store ect; hobby lobby, garden ridge ect… They usually have those heavy duty card board sheets, just not sure how thick or durable.
    This morning it is 32 degrees in the DFW area, I just went into my double car garage and its 50 degrees at 8am. Since I finished, I stayed out there for the last 2 days doing some more prodjects. With a small space heater I was able to keep garage at 60 degrees. If anyone is interested I installed a recirc pump that they say will save me 12,000 gallons of water per year, that’s 1,000 gallons per month. Took all of about an hour and a half from start to finish… Tim

  6. Anonymous

    Finished. Found out that my close out panels are part plastic with foam in the center, I am probably at R-13-R15. Added 60 lbs to double garage and 30 lbs to single garage. Had to tension springs 2 full revolutions and adjust up and down force on opener. extremely quiet door now. Last few days here in DFW area has been 32 or less at night, my garages are staying 50-52 degrees first thing in the mornings. Well worth it. I got my panels from work, they came in some shipping boxes protecting material. They started out at 56″ X 22″ I cut them down to 49.5″ X 20.5″. Other than that I really don’t know where to tell you to look. Search these words online; econolite and gilliner. These are 2 products installed on argo planes to save on weight but pretty strong as well. Good Luck… Tim

  7. Anonymous

    Great Comments and ideas! Where do I find thin vinyl or fiberglass sheeting? I have a wooden door with metal bracing and no channels. I have 1.5″ (R-18) thick Isocyanurate foam sheets. I will have metal U-brackets made to hold the foam in place. I would like to face the visible form with a “thin” vinyl or fiberglass sheet. Where do I find such thin vinyl or fiberglass sheeting? I plan to roller contact cement to attach this sheeting much like laminate on a countertop but I want it thin because of weigh considerations. Thank You.

  8. Anonymous

    Currently installing Regular R-13 bat insulation onto garage doors. Bats are 3 1/2″ thick so they stick out about 1 1/2″. I am also applying a fiberglass 1/8″ thick close out panel on each pocket panel of the doors, this gives a very nice close out look and very clean. I compress the insulation a little when insalling the panels over insulation so I actually get about R-12. The best kit would only offer R-8. So far I have spent a total of 35 bucks for 3 car garage. Kits go for 68 for each single section. Yes I will adjust spring tention due to weight. Will update later. Good luck… Tim

  9. Anonymous

    what about the top of the garage door. I want to cover up the opening between the top and the frame.I have used the R-19 insulation to help keep out some of the cold air,but now I have been looking through the net to find rubber for the top.

  10. Anonymous

    I bought the reflectix and the foam sheathing as described by the post by nickel. I suppose I put the foil in first (against the panel) and then the sheathing? Should there be a gap between the foil and the door panels? How should I hold it in place? Foil tape? Thanks.

  11. Anonymous

    Just like the last post, our baby’s nursery is right above our garage. I unsulated the door with the foil bubble wrap (Reflectix) and 1.5 in. foam sheathing. I attached it with an all weather duct tape for metal, and so far it’s holding up perfectly.

    But I think even more beneficial for insulating our garage from the baby’s room above – I bought 1 3/4″ x 4′ x 8′ poly shield foam board and attached it to the ceiling of the garage. I put the foil side touching the ceiling. The room is immediately 10 degrees warmer. I just attached that using roofing nails to hold up the sheathing to the ceiling.

  12. Anonymous

    We have our nursery right above the garage with an uninsulated metal door. Last weekend I insulated our metal garage door as you suggested above. Eureka! What a difference. Cozier, more comfortable and for less than $100. Thanks a million. The only suggestion I have to add is not to forget to replace the bottom threshold seal (the rubber on the bottom) of the door and the seals in front of the garage door attached to the house. Thanks for everything.

  13. Anonymous

    Nickel–How has the double bubble foil radiant barrier worked out for you? Better results than the foam board? Also, how did you attach the bubble foil to the door….double stick tape or foil tape? Or other? Am planning to purchase next week and get the project done before the cold weather. Thanks for the ideas.

  14. Anonymous

    Great Idea! I went and bought the panels at HDepot, cut them to fit and was done installing the panels in two hours.’
    This is the easiest “do it yourself” job you can perform with maximum benefits. The HDepot sells the 1 1/2″ panels and it seem to be the most economical way to go. I would waste my time with the 3/4 inch 4′ x 8′ sheets.

  15. Anonymous

    When you squish that R13 insulation down by covering it with the foam board, it no longer has an R13 value. The airspace within the fibergalss insulation is what gives it its insulating properties. I really dont know what it would be but it may be no better than two layers of the 3/4 foam board.

  16. Anonymous

    I insulated my metal garage door with foam sheathing from Home Depot. It was pretty easy and inexpensive, but when the door warms up in the afternoon we’re getting a heavy vapor smell. Now I have to leave the door partly open. Has anyone else had this happen?

  17. Anonymous

    Just wondering, will insulating my garage door cut down on the moisture that I have been getting in my garage? In the summer, I have a dehumidifier running constantly in the garage and it needs to be emptied at least every other day. My tools are also rusting. I need a solution!! Please help!!


  18. Anonymous

    My door is 16’by 7′ with hurricane braces in the middle of each pannel.I used 3 rolls of R-13 fiberglass installed verticaly $9.68 each,and covered by 3 rolls of 2′ by 25′ of the foil covered bubble wrap $27.62 each installed horizontaly. Total 120.94 plus tax at Lowes. Painted the inside exposed metal with silver spray paint, looks like something from NASA.
    I know the foil is supposed to go against the metal, but with all the R-factor of the fiber glass, I’m more conserned about fire and appearance. Didn’t need tape at all.

  19. Anonymous

    Easy solution to the carbon monoxide worry: Don’t run your car in the garage! Shut it down before closing the door and open the garage before starting the car. Then SEAL that garage door as best you can with stripping. You will save energy and not have to worry about CO. (Unless you are in the CO detector business, a little common sense goes a long way!)

  20. Anonymous

    A question for comment #31 from William…thanks for your great step by step. What is the size of your garage door? Mine is one big door for a two car garage. I was just wondering if six sheets would be enough for me.

  21. Anonymous

    A few thoughts from an arctic engineer in Alaska to those wanting to insulate their garage doors:
    1) If you have combustion or air-demanding appliances (clothes dryer, water heater, furnace, woodstove, stand-alone gas heater,etc.) indoors, they need combustion air. if you weatherstrip the garage door, you need to provide a makeup source of outside air for the appliances – your plumbing and heating store can calculate how many square inches of clear air venting you need based on appliance ratings. The codes require this for new construction anyway, so garage door vinyl flexstrip along the door jambs inside and outside can really cut down the cold inflow.
    2) Spray-on or rigid foam insulation is easy to use and apply, but is a fireman’s nightmare. Code requires fire-rated drywall over foam insulation (1/2 or 5/8″ depending on code applicable) which kills it for use on a door because of weight. Rigid or spray-on foam urethane or styrene insulation is easily ignited and goes up like a blowtorch, and generates really impressive amounts of killer smoke and poisonous gases – not something you really want in an attached garage or shop. There are more and more deaths occurring in house fires because of the use of foam insulation, commonly in garages or shops attached to houses, where the family can’t get out before becoming overcome with foam-produced fumes and invasive flames.
    3) That’s why the commercial garage door insulating blankets are foil-covered non-combustible fiberglass or rockwool batting.
    4) And yes, especially for a 16′ (double-wide) door, the weight is enough you need to get the springs tightened to compensate, or you will wear out your garage door opener. The springs are not something to mess with unless you are a pro – they can take off a hand or arm if you lose control when adjusting tension.

  22. Anonymous

    I just completed my garage door insulation as decribed in the first article. My garage door is 16 x 7 with hurricane bracing on each of the four panels. I used six sheets of 3/4″ insulfoam (Lowe’ Item # 15355.) The material was a perfect fit, as I doubled up the panels to fit in the channels of the door. I faced one “foil” side toward the door as a radiant barrier and one inward to do the same. Around the windows in the top panel, I cut smaller pieces of insulation wherever possible and tied the insulation into the window frames with aluminum tape. This gave me about a 1″ recess pocket around all the windows, which I covered with a shrink wrap kit. (Lowe’s Item #: 61805) It took me the good majority of the day to complete this project, but it wasn’t difficult.

  23. Anonymous

    Has anyone captured how to insulate the door when it has windows in the top panel? I am going to attempt to apply plastic, similar to the way you winterize windows in your home. Double sided tape and shrink-wrap plastic is my plan. I’m on my way to Lowe’s for supplies. The other panels in my 16′ x 8′ metal door will be a combination of insulfoam and radiant barrier (thx nickel.) My doors have hurricane bracing, which add weight, but should hold the product in place. I am worried, however, about the 1/2 hp garage door opener failing, as it already sounds like it works overtime. I’ll let you know how it turns out.

  24. Anonymous

    After reading all of these posts, I’m off to Lowe’s for materials. My 16′ x 8′ garage door has windows in the top panel. Has anyone come across a way to tackle this? I plan to use plastic as a barrier, though I am sure I will lose out on the effectiveness of my insulation job. I enjoy the light that they let in, so covering them is not an option. Any ideas?

  25. Anonymous

    Wow – what great suggestions! I’m looking to do this ASAP as well. Does anyone have a link to some good R-13 fiberglass insulation? I want to know what to get when I go to the store. Is this the right stuff?

    I’m going to use JWSmythe’s plan up there. My door is old and wooden and I’m converting the garage into rehearsal space for my band.

    Do I really need to do the fiberglass and then the foam sheets on top or will just putting the insulation in the inset panels and covering it with the tape be enough?
    It gets pretty chilly when it snows here in NJ!

    Thanks again!

  26. Anonymous

    Good posts – with regards the gap at the edge of the garage door for CO ventilation: you can purchase an automatic garage door closer that can be linked to a CO detector.

    If the CO detector exceeds safety limits, the garage door openner will automatically open the garage door and allow fresh air in. The door will not close until either you override (dumb) or CO levels drop to normal (smart).

    The system I have is a cheap one about $40 (the CO detector is a top-of-theline one with built-in explosive gas alarm). I think the automatic closer is made by Skylink. The best part is I no longer worry about forgeting to close the garage door when I drive off to work.

    BTW – never start or run your car in the garage without first opening the door. With a little DIY know-how, you can connect a timed exhaust fan through your wall that comes on when you open the door and shuts off 30 minutes later. That will extract fumes after you leave the garage and have closed the door. Although, unless you drive a 1944 Sherman Tank, it’s unlikely you’ll put enough crap into the air to warrant such a DIY job. but great for days when you ate too many beans. 😉

  27. Anonymous

    At my home in Montana winters can get down to 45 below and it is common for us to have highs stay below zero for up to three weeks straight. I’m currently investigating the best way of blocking the cold air from blowing in from the sides of the door. I don’t care about the harmful fumes, as I will open my door before I start the car. I want the garage to be warm when I’m not in there.

  28. Anonymous

    Cheap solution: cut 3-1/2″ x 15″ insulation into strips to fit vertically inside door panels(22″ in my case). place strips inside 13 gallon kitchen garbage bags as vapor barrier. place strips/bats into panel (3 wide between vertical angles in my case). Use foil tape around and between strips/bats to mount to door panels.

    I used 48 pieces of insulation 3-1/2″ x 15″ cut 22″ long($25) and 48 garbage bags($5)plus 600′ foil tape($25). Total cost ($55)

  29. Anonymous

    Well Thanks everyone! I saw this once about 5 or 6 yrs ago on one of the Home shows, but couldn’t find any info on how to actually do it.

    I have a 1 car garage that’s too small to park in so I need to insulate it. I’m headed to HD later today to follow Josh’s plan. R-13 Fiberglass and foam to hold in place, with Metal duct tape. I’ve seen the kits on the web and the highest R-value they offer is about a 6. And I’ll remember to have my door opener serviced to adjust the tension (master service contract). I wouldn’t have thought to do that.

    As for the sides, we can see daylight from the sides of our door even with weatherstripping on the outide. I need a viable solution for sealing out as much air as possible from the sides. Since we don’t park in there, it’s like a craft/hobby room I don’t need to worry about carbon monoxide issues, etc…

    Any ideas on that?

    This has been the most helpful post/website I’ve encountered. Thanks again!

  30. Anonymous

    Hello you all! I’ve been serching the net for just such a Project. I live in Queens NY, and have an attached garage. The door is an old wooden door and i was contmplating changing it. But after seeing the costs, i started loking at other options. I Like what i see so far and am going to try it.

    In terms of the vents or holes at the sides of the garage door for Monoxide release, i think it all depends on what you plan to do with the garage and also, like my garage they sometimes have windows, so ther are other means of escape for the deadly gas.

  31. Anonymous

    Hey I was quite surprised to get such a quick reply. The foil covered bubble wrap is an excellent suggestion. I got familiar with that material in my current home when I realized the HVAC contractor was not required to insulate the metal ducting in the gas forced air heat system here. The stuff is quite agreeable to work with (vs the glass insulation thought) and I think will represent much less of a load change on the opener motor / drive. A neighbor did this insulation upgrade using stryro-foam sheet on his high-end rapid open system and within a year the drive coupler disintegrated. So I was concerned about the weight. No more.

  32. Robin, I can’t recall the exact cost, and it depends on exactly how you do it. The foam sheathing is roughly $10 per sheet (maybe more like $12) and it’s 4 x 8 ft. You can figure usage from that. If you do a double-layer like I did, then you will double the cost. The foil tape will also add a bit in the way of additional costs.

    I actually just re-did this for our new house, but used a radiant barrier (basically bubble wrap wrapped in foil – you can buy this by the roll) backed by a single layer of foam sheathing. I think I used three 25 ft rolls of the radiant barrier plus
    Just guessing, I probably spent $125-$150 to do this. We get far more than the energy savings in return, though – it also makes the living space above the garage much more comfortable.

  33. Anonymous

    Thanks everyone for all the great input on this subject. I have been planning to do this for some time now and you guy have taken all the guessing / trial & error out of it for me. Just one question. No one mentioned anything about cost of this project. Mine is a double space garage. I would like to have a feel for the cost.

  34. Anonymous

    I have the gaps on the side of the garage door as described above for ventilation according to the post. I am considering insulating my ultra thin metal garage door, but doesn’t this seem like a waste considering there are gaps on the side of the door that let a decent amount of hot/cold air into the garage anyway.

  35. Anonymous

    I have been wanting to do combination insulation/foam sheathing also. After you installed both sheathing, what did you secured foam sheathing with. Also does it make a big diffrent with both or just one type or another?. appreciate any ans. for your info 112 degree yesterday. In my Garage which faces east in the after noon it was 118. Garage door about 1 feet open and side dooe open no help. Tony

  36. Anonymous

    I have read through all these comments and particularly thank Josh for the great idea of using a combination insulation/foam sheathing. I will be heading down to HD or Lowes today.

  37. Anonymous

    sealing the sides is a NO-NO. I remember reading some other site, which questioned the gaps in the sides of the garage. It is there for a reason, to let the car fumes exhaust, prevent carbon monoxide build up. (also it might be the law in some places). Some energy efficiency has to be sacrificed for safety.

  38. Anonymous

    Why don’t you do what I did and use fiberglass rolls for the core and foam sheathing to hold everything in place. I then took the metal duct tape to seal the foam to metal door panels, all of which I muddled together taking tid-bits from this thread. My wife gets mad now, because now I spend to much time in the garage. Thanks for all of your posts. Without them I would still be shivering and busting cold knuckles out there.

  39. Anonymous

    Sorry for adding onto a very old post.

    I just did something similar a couple months ago. I’m in west central Florida (Tampa area), and the lows were predicted to be in the low to mid 30’s. I wanted to continue working on an outside project, and have a smoking lounge.

    I used 3 1/2″ thick R-13 fiberglass insulation. Like the article’s description said, I stuffed it in the U-grooves of the panels of the garage door, and taped it in place with the metal duct tape (like you’d use to tape air conditioning ducts). I put the insulation in vertically, as it wasn’t wide enough to fit horizontally.

    I chose the 3 1/2″ R-13 fiberglass for it’s insulation value. While I am compressing a small part of the fiberglass to fit it in the U-grooves, the rest is pretty much at it’s natural thickness. This is a FAR superior insulation value than the foam sheets. If I remember right, the highest R value I could get was R-6. It was a lot cheaper to buy a few rolls of fiberglass than the foam board. Most importantly, it fit better in my car.

    I’ve encountered two problems, which are related. The first is that you have to be careful on the length you cut each panel. At first, I was cutting them a little too long, to make sure they’d have plenty of insulation to stuff in the U-grooves. This left the panel bulging out a little.

    The bulging panels are now blocking the electronic eye, keeping the garage door from closing with the motor. We’ve retaped the overly long panels a few times, but they keep popping loose. The panels that were cut to a more appropriate length are still sitting flat and happy.

    I just need to cut some tape, cut a little length off those panels, and retape it. It shouldn’t be much of a headache. It will be impossible to remove the old tape without tearing the paper backing.

    Ideally, the paper side should be covered with something. I may cover them with some sort of wallboard in the future.

    Be careful not to tape over the seam where each door panel bends. The panels seperate slightly, and that may cause binding if your tape is REALLY strong, or more likely your tape will come loose, and pieces will come off. My girlfriend re-taped quite a bit one day, and now the garage door makes a popping sound when it opens, as the tape comes loose from the panels. Luckly, that’s not the same pieces of tape holding the fiberglass panels in place.

    When it was in the low 30’s outside, it didn’t drop below about 60 in the garage.

    Since then, we’ve had warm and cold days. You have to love Florida winters. The garage has held a nice moderate temperature. In it’s coldest, I’ve only had to wear a light jacket to spend any length of time in there.

    My garage has a brick wall on the outside, and poorly insulated inside walls. I believe this has made a difference in the HVAC bill, but I’m not positive, as we haven’t lived here very long.

    Just after doing the insulation, I needed to work on a car when it was rather cold out. It was very nice working on it in the garage. The cement floor was still a little cold, but not like it would have been outside.

  40. Anonymous

    I just did the sides of mine yesterday. When the wind blows, it tends to push the door into the track more , which creates a gap for the wind to come in. I ran 7/16″ weather strip along the edge of the door’s frame so that the edge of the foam just touches the edge of the door. A staple at the bottom keeps the bottom water strip from grabbing it as the door raises. Seems to be working so far.

  41. Anonymous

    When you did this, what did you do about the sides? I live in Florida and wishing to insulate a garage door so the garage can be used as a playroom for the kids. I was going to use the foam sheets which are cheap at HD and Lowes, but I am unsure what to do on the edges of the door. Can you help?? I know you posted this awhile ago, but hoping you still check and update. Thanks


  42. The tape was still up after a year and a half when we moved. Winters weren’t nearly as cold, but I’m willing to bet our summers were consistently hotter and the tape didn’t fall off.

  43. Anonymous

    I am new to this. I just started my own business selling automatic garage door locks. Do you think there is a market for this? It works with any existing garage door opener and install in a little over a hour. It locks the door when you close it and unlocks the door when you open it, there is an option that will automatically close the door from 5-20 minutes in case you forget to close the door.

  44. Anonymous

    Foam sheathing is flammable and meant to be concealed by drywall, cement board, or fire-resistant plywood. The garage insulation kits have a vinyl coating which I presume is meant to keep fires at bay. Apparently, if a fire gets started, your garage door will go up in a flash!

  45. Anonymous

    Also make sure that there is rubber between the door and the floor and that the door is as weather tight as possible.

    This is not only an issue of cold air. It is also an issue of moisture and insects. You want neither of those three inside your garage.

  46. That’s a good point, Vincent. I suspect that I did throw the balance a bit out of whack, as our garage door opener sounds like it’s working a bit harder than before. I’ve been meaning to check this, but haven’t had a chance to do so yet.

  47. Anonymous

    After doing this you might want to make sure the garage door is still balanced. The spring tension might have to be adjusted to account for the extra weight of the insulation.

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