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I have an attached garage. There is no living space above my garage, but one length of the garage runs parallel with the house. I've attached a lovely example. Currently, the garage has sheet rock on all of the walls. There is insulation behind the sheet rock. Additionally, our garage door is insulated. I want to insulate the ceiling and start having a much warmer garage in the winter. The garage goes to a peak in the center, like an A. The ceiling joists are spaced about 22.5 inches apart. My idea was to buy some rolls of insulation and staple them to the roof. I do not intend to add sheet rock to the ceiling at all. I do not have a furnace in the garage currently but may consider adding one in the future. I work on my vehicles a lot and generally do lots of stuff in the garage all year round. Currently I freeze my rear end off in the winter. If I do what I described above, without adding a furnace, will my garage be any warmer than without any insulation in the winter? We park our cars in the garage, so as they cool down, I imagine a lot of that heat would remain in the garage. Even when we don't drive the cars, the house is bleeding out some amount of warmth and the garage shares 1 side with the house. Heat would leech off the house and passively warm the garage, at least somewhat. Is it as simple as buying some rolls of insulation and stapling them to the ceiling? Do I have to worry about the insulation falling down or drooping or anything? I have not yet considered costs, but I expect it will be several hundred dollars. I have measured the garage to be 414 sq feet, though I think a 36 ft^2 region is insulated already (that section is covered with sheet rock). Any tips or anecdotes whether this will keep my garage warmer even without a furnace?
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Nov 22, 2015 04:11
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| # ? Apr 26, 2024 16:37 |
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It'll work. My old man and I did pretty much this to the attic space above our garage for a game room when I was growing up. Staple more generously than what you would think on those side flaps, and it'll be no problem. That being said, I'd still do the sheet rock eventually if only to not look like poo poo.
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Nov 22, 2015 04:33
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Claverjoe posted:It'll work. My old man and I did pretty much this to the attic space above our garage for a game room when I was growing up. Staple more generously than what you would think on those side flaps, and it'll be no problem. That being said, I'd still do the sheet rock eventually if only to not look like poo poo. Thanks for the quick response. I am glad to hear it worked. As for the sheet rock, I don't want to have the lower ceilings. Right now, I store a bunch of ladders upright in the back and it's awesome. Additionally, I wouldn't be able to jack my truck up and work on it in the garage (at least not with the hood open). Also I have a really big stereo system out there and if the ceiling was sheet rocked, sound would reverberate way too much. If there were ways around these issues, I would totally do it because I agree that garages with sheet rock ceilings look way nicer than exposed ceiling joists. edit: and I have (2) 400W halogen lights hanging down from the joists. I think having a white ceiling would make it too bright. Maybe that'd be a good thing, though, and I could drop down to less-wattage bulbs. Did insulating the garage help keep the garage any cooler in the hot summers? Did it make them even hotter? Mine gets sickly hot in the summer now, but I don't know what effect on that insulation along the (currently uninsulated) ceiling would have. johnny sack fucked around with this message at 04:54 on Nov 22, 2015 |
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Nov 22, 2015 04:51
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I'm not a carpenter or anything but I have helped insulate a couple garage roofs and some foam ventilation baffles were always used between the rolls of fiberglass insulation and the plywood roof sheathing. I'm pretty sure both garages had ridge vents and that's why.
BlackIronHeart fucked around with this message at 10:53 on Nov 22, 2015 |
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Nov 22, 2015 10:50
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Exposed fibreglass insulation will get pretty dusty. Consider lining the rafters (angled bits) with the joists (horizontal beams) sticking through. Also, putting a staple through fibreglass insulation will compress it rendering it less effective but someone mentioned tabs on the side for stapling so if that's the case fine. I'm not familiar with weird American building materials.
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Nov 22, 2015 20:51
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You need a vapour barrier on the insulation (on the hot side) to prevent condensation in your insulation. So you either need to buy the rockwool/fibreglass with a aluminium layer or add a seperate vapour barrier yourself. Also some aluminium tape to seal up the edges and maybe some PU foam to seal any other weird gaps. The aluminium will be way more reflective than even the white paint though.
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Nov 22, 2015 22:15
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NihilismNow posted:You need a vapour barrier on the insulation (on the hot side) to prevent condensation in your insulation. So you either need to buy the rockwool/fibreglass with a aluminium layer or add a seperate vapour barrier yourself. Also some aluminium tape to seal up the edges and maybe some PU foam to seal any other weird gaps. Okay, this sounds like a useful tip. So do I need the ventilation baffles [i]and/i] a vapor barrier? Can the vapor barrier be the same type that you lay on a concrete floor - ie the big sheet of black fabric?
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Nov 22, 2015 22:48
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How is your garage roof vented, if at all? Do you have soffit vents and a peak ridge vent or gable end vents? You need to leave a 1" air space between the insulation and the roof sheathing running all the way from the overhang to the peak. Consider using vent shutes to maintain the air space if you want to use bat insulation because of price. How deep are your rafters? 4by, 6by, or engineered? That'll determine how thick you can get your insulation. 4by is like R-13 or 14, 6by is R20 or 22. Also, your 22.5" rafter are 24" on center. 24-1.5 for the width of the 2by4/6 rafters. This is a standard rafter spacing for 23" insulation. You should price out using rigid foam board as spacing between the roof and the bat insulation. They can serve as your vapor barrier if they're 2" and you seal them with canned expanding foam around the edges where it meats the rafters. Plus, they'll give you R-10+ in addition the the bat rating. So from outside in, it'll go sheathing > air space > rigid foam > bat insulation with no paper backing. The no backing is important. You don't want another vapor barrier. If you're just using bat with no foam board, you want the bats with paper or aluminum (better for reflecting summer sun radiation hitting the roof) vapor backing facing the inside, stapled on the 2" end of the rafter, overlapping the flaps. If you have anything in the garage that'll put out a ton of vapor in the winter, like a ventless gas heater, use bat insulation with no vapor backing. Instead, use polyvinyl sheet vapor barrier and tape the seams so that you don't have hot moist air passing through the insulation and condensing on the cold roof sheathing. This will soak and compress your insulation and rot your roof sheathing. Get a quote for closed cell spray foam. You can probably have it sprayed right against the sheathing filling the rafters. It's a vapor barrier and will completely seal against the roof sheathing so you don't have to worry about keeping air flow up the rafter space. You MAY be able to skip the air space if you glue 2" foam board directly to the sheathing and seal around the edges with canned foam. Make sure you use construction adhesive meant for foam board, otherwise it'll dissolve. Run the foam board from peak down into the overhang, then seal the overhang off from the interior by putting foam board vertically up from the wall header to the roof. Don't insulate the horizontal soffit or seal up the soffit vents. goku chewbacca fucked around with this message at 05:33 on Nov 23, 2015 |
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Nov 23, 2015 05:03
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johnny sack posted:Did insulating the garage help keep the garage any cooler in the hot summers? Did it make them even hotter? Mine gets sickly hot in the summer now, but I don't know what effect on that insulation along the (currently uninsulated) ceiling would have. You'll need to put a wall mounted A/C unit somewhere in there if you want it at a comfy temperature if you got hot summers. We used a big one (12000 BTU unit I think) for that attic game room, and it worked well enough. Also, yeah, it's been (oh god, almost 20 years) so I've forgotten that rather important detail, but yeah, you need a vapor barrier, but that isn't too bad to do that either.
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Nov 23, 2015 05:31
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goku chewbacca posted:How is your garage roof vented, if at all? Do you have soffit vents and a peak ridge vent or gable end vents? I just double-checked but I don't think my garage is vented at all, really. The garage used to get so unbearably hot during the summers that I installed 2 of these on the roof. It didn't really help much. The plywood comes together at the peak of the garage, there is no gap for ventilation, and there is no vent coming out of the shingles at the peak, either. Additionally, the exterior soffit has no ventilation, either. If that changes anything for how I should or should not insulate the garage, let me know. I'm more and more tempted to just hire someone, the more responses I get.
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Nov 23, 2015 23:12
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| # ? Apr 26, 2024 16:37 |
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"Rascal, are you here? Do excuse me, I thought this was the dog shed for a moment." "With that amount of water leaking you'd think you would be in a nursing home by now." "A fitting place for the leader of UKIP. Oh, I read that last name wrong!" Other than that I have nothing. edit: Disregard, I misread the thread title. lllllllllllllllllll fucked around with this message at 12:35 on Nov 26, 2015 |
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Nov 26, 2015 08:52
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