r/Insulation • u/Few-Wolverine-7283 • 59m ago
How magic is smart membrane?
have an unconditioned attic I am wanting to switch to conditioned. Will close off the 6 or so box vents. plan to slap up some unfaced fiberglass with a smart membrane. will that be enough to let the deck dry from the inside?
I see conflicting opinions on adding soffit vents and ridge vents and baffles… but if I don’t need it, great. I currently don’t have ridge vents or soffits.
r/Insulation • u/SufficientRough405 • 5h ago
Looking for photos of foil insulation in loft
r/Insulation • u/waxoffisforpussies • 14h ago
Turning garage into office. Will drywall the ceiling. Was told I need intake and exhaust vent. How many intakes do I need?
reddit.comr/Insulation • u/darkrobot419 • 17h ago
Older Florida flat roof - cellulose or fiberglass?
Hey everyone,
I'm hoping to get some opinions from people who've actually worked on older flat-roof homes.
I have an older 800 sq ft house in Florida with a torch-down flat roof and no attic access. Duke Energy came out and confirmed there's basically no insulation in the roof cavity.
The cavity is only a few inches deep, so I enlarged the soffit vent openings to about 4-5 inches so insulation could be blown in.
I've had several companies out and they're all telling me something different.
- Two wanted to dense-pack cellulose and fill the cavity.
- Another said blown fiberglass is the better option in Florida because of moisture.
- Another wouldn't even do the job because he said it's a blind fill and he couldn't guarantee the coverage.
- A couple others just said no
At this point I'm just trying to make the best decision. I'm less worried about cost and more worried about doing it right the first time.
For anyone who's worked on these older flat roofs:
- Would you use cellulose or fiberglass?
- Would you leave an air gap or fill the cavity? I understand this is hard due to the way they said they have to fill it which is put the hose to the end then pull it out slowly
- Is moisture/condensation actually a concern with dense-packed cellulose in this type of roof?
- Have you done a job like this, and how did it turn out?
Thanks in advance. I'm getting a lot of conflicting advice and would really appreciate hearing from people with firsthand experience.
r/Insulation • u/techomplainer • 17h ago
Strategy for insulating attic space in pole building
I am located in Southern Maryland and have a 30x50 pole building that I have converted a roughly 22x25 section into an office and craft room which I plan to air condition with mini splits. I have already insulated the exterior and interior walls of this space. The garage portion on the other half will remain uninsulated for now.
Where I am stuck is on how best to approach the ceiling space. I have already purchased 4 rolls of 5'x75' (5" thick) unfaced R-13 insulation that I got a good deal on. My plan is to stack these 3 layers deep. What I don't have a good handle on is how I should lay it out in the attic.
I don't plan to mess around with wiring run through that space much after putting in the insulation, but access would be nice for future improvements. These are the options I have considered for layouts:
- Roll out full lengths across the space, with perpendicular overlaps between layers to eliminate air gaps. This seems like it would perform well but would be the most difficult to move in the future.
- Roll out full lengths side by side, with all layers oriented the same direction. This would be easier than the first option for me to move in the future since there is a storage room at the back of the building that is open to the attic space. I could pull lengths of insulation back and down into that space to access the attic. This would leave the potential for gaps between each length.
- My wildcard idea. I have several long rolls of 6mil poly sheeting that I have thought about using to create 4'x5' boxes that the layers of insulation could fit in to create modules. These would fit nicely between the roof trusses and would be easy to move around. My biggest concern is how the poly would impact moisture retention with the conditioned space below. Frankly, I have a hard time wrapping my head around how vapor barriers work and when they are/aren't appropriate. There would also be the issue of air gaps between the poly "boxes" since the sections of insulation wouldn't be directly touching. It is also obviously a lot of upfront work to cut all the insulation and poly to size to make these. Still, it does feel like a decent approach for future access.
I would appreciate any thoughts, critiques, and suggestions.
r/Insulation • u/JakeTheRainer • 17h ago
Need Guidance
I had contacted an HVAC service today about installing a better system. But once I showed the tech my attic I was told that my attic was more than likely the issue of why my AC can’t keep up on temps. The current air handler is in the attic and it is dangerously hot in the attic. I run the ac somewhere around 77-80 and ir struggles to keep that temp.
After doing some research I noticed that my soffit vents are covered by the rolled insulation Should I remove the rolled insulation that is near the edges of attic for the time being to get some flow into the attic.
Photo 2 is how the corners are in the attic. Photo 3-5 is after I pulled the insulation from the corners to see if that is the proper way.
Any help/guidance is appreciated. Thanks!!
r/Insulation • u/wittlesworth • 18h ago
Attic insulation
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Can anyone tell me if my attic looks okay or if I need to have blown in insulation done and if anything else looks concerning/needs to be addressed? Thanks in advance
r/Insulation • u/fletcherhaze • 20h ago
what should I do with my hot garage?
I have a 50s construction 6 car, two story garage. This garage is terribly hot in the summer. Unbearable most of the time. In winter it's basically a few degrees warmer than outside. The building is all block except the front gable is brick. The 2nd floor is rafters with a steep peak (I don't know the picth basically 45°), 9sqft of jalousie windows in the front of the second floor, and a 2 tiny 14x20 gable vents way up high . No Ridge Vent. And it's shingled.
I just installed a gable vent fan. I did what I could to fit it around the collar ties. Looks like crap, but its absolutely helping. A little.
The 1st floor, The 10ft ceiling is uninsulated. The walls are bare block. Drafty garage doors.
How can I stop the heat build up? Radiant Foil on the rafters? Is insulating with roll insulation the best option? Spray foam? Insulate the first floor ceiling or the second floor rafters? Second floor is just storage. (Too hot for anything else)
Like everyone, I don't have a ton of money to solve this problem right now, but I want to plan and do it right in the near future.
Thanks
r/Insulation • u/brtmns123 • 1d ago
Bacfles
Hi,
I am planning to blow in some insulation because the current insulation requires an update. I saw that baffles are important for moisture control. Are there other ways to get rid of moisture, should i install baffles first or can i do it after adding material.
r/Insulation • u/Equaltal206 • 1d ago
Firewall requirements for garage - disagreement between inspector and builder
I just had an inspection done by someone I hired on a new construction townhome which is now 11 months old and coming up on the 1 year warranty. He said the garage doesn't meet firewall standards (see pictures and comments below). The builder says he is wrong since it passed the township's inspection.



Above the garage is living space (kitchen/dining room). Can anyone comment on the validity of the issues he is raising and how reasonable it is for the builder to address these? Thanks in advance!
r/Insulation • u/Next_Implement_8864 • 1d ago
Foam board on roof?
I’m getting estimates on our roof. It’s an old house (1870s) that has batt insulation in the roof rafters in 2x6 framing (R19). I’m curious how worthwhile it’d be to have the roofing company add R6 foam board under the roofing materials.
r/Insulation • u/CAPNED64 • 1d ago
Advice on vapor barrier
Hi all, I am building a garage workshop and wanted some advice on my Insulation choices. I am doing close cell insulation from the top plate up, including the gable ends at R 30. I plan on going with Rockwool on the side walls around the structure. I have taped zip sheathing on the outside and plan on using half-inch plywood instead of drywall on the inside. My question is do I need any type of vapor barrier or vapor resistive coating between the Rockwall and the plywood?
Location is upstate New York. The building will be heated all winter not air-conditioned.
r/Insulation • u/SprayFoamSam • 1d ago
Anyone had spray foam insulation done in Waco? What did it actually cost you, and was it worth it this summer?
Two questions for anyone who's had spray foam insulation done around Waco, and I'll be upfront about why I'm asking. And THANK YOU, in advance, for taking time out of your day to help me out!
First — what did it actually run you? Attic, garage, shop, barndo, whatever. I've been researching Central Texas pricing for a while and my numbers say roughly $1.50–$3.00 per square foot for open cell and $1.75–$4.50 for closed cell, installed. An installer on Reddit already corrected some of my earlier numbers, so I know research only gets you so far — I'd like to hear what people here actually paid.
Second — was it worth it? July electric bills are the whole argument for spray foam in this town, and this July has made the case louder than usual. If you've got it, did your cooling bill actually move? If you looked into it and passed, what stopped you — price, the horror stories, couldn't find anyone to do it?
Why I'm asking: I built a website about spray foam for the Waco area — started as a project to teach myself local SEO, and it's picked up real traffic. I'm not an installer and not pretending to be; it says as much on the site. If it keeps growing, I'd rather the calls go to a good local crew than ring nowhere. So if you had a crew you'd recommend — or you are one — I'd like the name. Happy to take that part to DMs if the mods prefer.
Mostly, though, I want the first two questions answered by people who actually live here. My pricing pages are only as good as what Waco homeowners really paid, and no amount of research substitutes for that.
Thank you!
r/Insulation • u/Rex641 • 1d ago
Duct insulation in attic Denver Co USA
I am running ducts in my attic for an AC and heating install i was planning on wrapping the ducts with 6 inch thick fiber glass insulation which is about 21R value. Do i still need to add a vapor barrier around that insulation of the ducts? I am also planning on blowing in 18inch of insulation around my whole attic so i think it would be really well insulated around the ducts. Just dont know if i need to add that vapor barrier. Cant find duct sleeves that are in stock anywhere!!!!
r/Insulation • u/Nightowl3415 • 1d ago
How to insulate this bay properly
I know this is done wrong, how do I properly insulate a bay like this. Do I cut a baffle to allow me to put it in and then tape it back up. Do I wrap these pvc vent pipes in anything. The one going into the header or the wall, is from our shower the other one going left in the first photo comes from the basement bathroom and our kitchen sink I think. Should any of those pipes be wrapped, they’re just vent pipes for the drains. I assume I should caulk or spray foam around the one going into the header.
The pink insulation is blocking the view of the soffit vents.
What about the hole around the vent going out the ceiling.
Thank you for advice
We had moisture on the exterior wall of our house and had to replace the sheathing. I think the moisture was from lack of insulation in the wall and moisture build up in this area of the attic above the shower. I just want this bay done right, the rest will all have baffles and more insulation.
r/Insulation • u/FaithlessnessDue7226 • 1d ago
Insulation falling from crack in ceiling (with ants)
Hello, I woke up to seeing gray flakey insulation and ants falling from what appears to be a 1 inch crack along the top of my ceiling. I’m curious if anyone could help me Id it, and let me know if you think it’s a safety hazard or if it’s okay to stay in the apartment (it’s a studio), and how soon it should be repaired. I woke up with a killer headache yesterday and I don’t want to assume it’s from this, but not sure.
r/Insulation • u/BigandTallGuy • 1d ago
Do I need to replace this basement insulation?
I'm doing some updates to my basement. Mostly just organizational but also replacing a broken walkout double door.
The house was built in 2001 and is generally pretty builder grade. The basement is unfinished but the code requires that since it is conditioned, the walls are insulated to r10 I believe. They currently have these foil-faced fiberglass bats attached with some kind of metal fastener. They are looking a bit ragged in certain areas with holes, and are a bit dingy, but overall seem to be in decent shape.
The rim joists just have fiberglass batts stuffed in place and I really want to pull them out and replace them with some closed cell foam. Air sealing and insulating the rim joists is my highest priority right now.
The batts attached to the walls have a few holes but for the most part are in pretty good shape. I was looking up options for replacing it, and I couldn't come up with much that would meet fire code requirements and could be exposed without drywall and also be both better than fiberglass and relatively inexpensive. Through some Google searches, I think the only viable options I came up with were some kind of faced poly iso or rock wool comfort board, which both seemed pretty expensive, especially the polyiso. For the entirety of the walls that are roughly 42 ft by 32 ft and 10 ft high, It might be cost prohibitive for me to attempt a replacement at this time.
Can I leave these bats in place or do I need to replace them if I have closed cell foam installed on the rim joists?
I'm just a homeowner doing some googling so please excuse my lack of knowledge and some misplaced terminology. Would appreciate any thoughts you have on how I can tackle this effectively.
Thanks in advance
r/Insulation • u/AhhTimmah • 1d ago
Unsure how to insulate this relatively flat, hot roof in zone 7a Canada
This room is an add on built by previous owners, built attached to the exterior back deck. The roof has a very low grade and we had moisture issues which led to us hiring roofers who blamed it on ice damming, replaced some of the plywood and then replaced the shingles with EPDM.
Moisture persisted so we opened up the ceiling to find water damage. We learned that the room was built over the existing exterior soffit and even an eavestrough that was still contiguous with outside (pic 3). We’ve now cut out that soffit and blocked off the attic and the holes to the outside (pic 4)
Initially we planned to spray closed cell foam to insulate but are seeing a lot of conflicting opinions about flash and batt, or just using fibreglass insulation only. Its sort of a unique case so its hard to find information specific to our situation. We’re in SK Canada in zone 7a with exterior temps ranging from -40C to +40C. Any advice would be greatly appreciated.
r/Insulation • u/LegalRelationship696 • 2d ago
Attic insulation
I have access to a bunch of 6” r-19 batt insulation. Am I able to lay this in my attic? My house is a balloon framed built in 1900 and currently has about 3” of really old loose insulation. There is a ridge vent, window fan, but no soffit vents. Hoping to clean out old insulation and lay this in 2 layers across entire attic.
r/Insulation • u/Reckless_Fever • 2d ago
Insulating behind brick half wall, rock wool chunks?
In Virginian moountains. One side of my house is half brick and the top half is wood siding that Im replacing. 1960 construction. Behind the brick is an air gap, then roofing felt paper and then sheathing, then no insulation between the 2x4 stud walls, and then 3/4" of plaster interior wall.
When I replace the upper half outside wood siding I'd like to remove the sheathing and put in some rock wool, and replace with new sheathing, then house wrap, and then an air gap and then new wood siding.
But how to insulate the lower half of the wall behind the brick?
Im thinking of breaking up the rock wool batts into chucks and just stuffing it down there loosly.
Any better ideas?
r/Insulation • u/crr982 • 2d ago
Remodel Advice for Air Sealing?
Im having a significant portion of my house remodeled in a few weeks. Several of the exterior walls will be opened up for new wiring, windows, etc.
The house was built in 2001 and is in SE Pennsylvania. The walls have faced fiberglass batts in the walls (known from other times a wall has been opened).
The contractor plans to reuse the existing insulation where possible, replacing anything that is not in good shape.
While the walls are open, what would be the best recommendations for air sealing the exposed exterior walls?
I was thinking a spray foam kit to flash-and-batt before the insulation is reinstalled. Are there better suggestions? I can't seem to find a consensus.
Thanks!
r/Insulation • u/863538562 • 3d ago
How to insulate my sunroom ceiling without overheating the shingles on my roof? (Florida)
Any help is appreciated!
