Lordoftheflies
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Insulation delivered. 44 bags. 33lbs each. 1320lbs total.
1947 Cape Cod Attic Insulation Advice Needed
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The tape will bond more permanently to facers than spray foam bonds to the unfaced cut edges of the foam board. It's not a terrible idea to take redundant measures for air sealing.
Yes, you are making the kneewall-attics conditioned space, while leaving the flat ceiling's attic space a vented attic. Without soffit vents and a clear path for venting each and even in the cathedralized ceiling area that's a reasonable way to go.
Air sealing kneewalls and the floor joists of the kneewall attics rather than insulating at the roof deck level for those spaces is something of a fools-errand (having played the starring role of "fool" in that movie several times now.) If you owned a blower door you could eventually get it right, but if you don't its FAR easier to get reasonable & reliable air tightness at the roof plane, which has almost no penetrations to screw it up, unlike kneewalls with it's electrical and the door/hatch penetrations, as well as all off the joist bays that pass through under the kneewall. I've seen the latter done right (not by me), but it's more time consuming, and almost impossible to do well without pressurizing/depressurizing the house with a blower and following the smoke pencil trails to the gazillion leak points.
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Lordoftheflies
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When a fool tells you not to do something you listen! Haha. Thanks I will need your advice and put up the foam boards on the rafters then.
I know it's a cliche but everything I'm doing I'm certain will be better than what was there....which was basically nothing.
Here are some pics. I spent the whole day in the attic spray foaming all the joints I could find and all the holes. Not too many protrusions actually but the vent stack, a few wires....
I know it's a cliche but everything I'm doing I'm certain will be better than what was there....which was basically nothing.
Here are some pics. I spent the whole day in the attic spray foaming all the joints I could find and all the holes. Not too many protrusions actually but the vent stack, a few wires....
Lordoftheflies
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More pics.
Lordoftheflies
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And some more.
Lordoftheflies
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Thank you Jesus my buddy is coming over tomorrow to help me with the cellulose. I'm hoping the orange store has an available machine or else I'm screwed.
Have you notices how well can-foam works as a hair setting gel yet? (If you think that's good, try fiber-reinforced duct mastic! )
Detailing the air sealing can be a real PITA, but it's a HUGE part of the overall solution, and really necessary to limit the amount of moisture making it to the cold side of the insulation layer where it can do real damage when taken up into structural wood as adsorb.
)Detailing the air sealing can be a real PITA, but it's a HUGE part of the overall solution, and really necessary to limit the amount of moisture making it to the cold side of the insulation layer where it can do real damage when taken up into structural wood as adsorb.
Lordoftheflies
Active Member
Lucky for me I shave my head myself every 2-3 weeks. So if anything it's a short term problem.
I think I will be able to do what I planned with the rafter vents - staple them together and slide them down the sloped portions on top of the existing insulation. I did remove the insulation from a few of the bays so that will a little trickier to get the bottom part shimmed up but I think I can do it with some of that 2" xps foam board I bought.
I might even show up tonight to get that machine rental as I don't plan on this taking more than tomorrow. Famous last words.
So if anything it's a short term problem. I think I will be able to do what I planned with the rafter vents - staple them together and slide them down the sloped portions on top of the existing insulation. I did remove the insulation from a few of the bays so that will a little trickier to get the bottom part shimmed up but I think I can do it with some of that 2" xps foam board I bought.
I might even show up tonight to get that machine rental as I don't plan on this taking more than tomorrow. Famous last words.
Lordoftheflies
Active Member
Actually I'm quite impressed with the control with the canned foam. It's not that bad. And for $90 I got more than enough foam to seal my rim joists. However, I have a water entry problem at the front door stoop because the ********* who redid the stoop didn't know what they were doing. They actually used the canned foam to try and waterproof the area. Shaking my head at these so-called "professionals".
I might have to tear the whole thing down and do it myself.
I might have to tear the whole thing down and do it myself.
Lordoftheflies
Active Member
Putting baffle vents in for rafters.
Looks good!
Make sure you extend the chutes up to well above your intended final depth in the upper attic so that you don't accidentally fill the vent channel with low density cellulose, and don't try to dense-pack the sloped ceiling bay or it will (in most cases) collapse the chute.
Make sure you extend the chutes up to well above your intended final depth in the upper attic so that you don't accidentally fill the vent channel with low density cellulose, and don't try to dense-pack the sloped ceiling bay or it will (in most cases) collapse the chute.
Lordoftheflies
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I didn't have of the rafter pieces so it's only a few inches above where I need to go. Aiming for r60 but will keep it below the rafter chutes.
Lordoftheflies
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Made a box of 2" r-10. Going to fill it with cellulose and spray foam it shut to some 2x3 supports in the opening. The opening is so small I can't screw in the supports until I'm out.
Some of the bags were way wider than 16" oc. Of course. I decided to add thinner slices of rafter be t and used spray foam on the edges where the vents were just a little too narrow for the bay.
Some of the bags were way wider than 16" oc. Of course. I decided to add thinner slices of rafter be t and used spray foam on the edges where the vents were just a little too narrow for the bay.
Lordoftheflies
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Also my gables are barely at 18" so r60 here I come!!!
Lordoftheflies
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All finished by around 9pm. Machine jammed up a few times. Down time was about 15 minutes total. Went as expected. Ended up using 34 bags (30lbs each) for about 50p sq ft minus a bit of fiberglass Batts installed when I put up the sheetrock...which, in hindsight. I didn't need to do.
Also in hindsight I should have installed the rafters vents above the bathroom before putting up the sheetrock since it was so tight there with the low pitch of the bathroom roof/dormer.
All in all it went pretty smoothly. I'm glad I ended up with more insulation rather than not having enough. I can probably return 8 bags no problem.
Clean up was a bit annoying. Good thing I used some painters tape on the two bedroom doors and the 2 closet doors. Dust got everywhere in the unfinished bath.
Thanks so much for your help @Dana. I was careful and tried not to get any insulation into the baffles. Thank God I had that tyvek suit too. Couldn't see anything through my glasses and thank goodness for my respirator as well.
Here are some pics. I was so tired I could hardly muster up the energy to take photos.
Here's the box I made out of R-10 2" foam board and spray foam. Used some screws to hold it in place. Currently it's sitting on some 2x3 strips in the hole in the ceiling and I'm going to button it up tomorrow with some spray foam and just sheetrock the hatch closed.
I just emptied the can of spray foam at the bottom of the box. Then I filled with cellulose and dense packed it by hand. I also dense packed the surrounding area a bit by hand since I didn't build a high enough dam and wanted to close it up anyways.
The bottom of this gable vent is just at 18". The other side was a bit higher.
Also in hindsight I should have installed the rafters vents above the bathroom before putting up the sheetrock since it was so tight there with the low pitch of the bathroom roof/dormer.
All in all it went pretty smoothly. I'm glad I ended up with more insulation rather than not having enough. I can probably return 8 bags no problem.
Clean up was a bit annoying. Good thing I used some painters tape on the two bedroom doors and the 2 closet doors. Dust got everywhere in the unfinished bath.
Thanks so much for your help @Dana. I was careful and tried not to get any insulation into the baffles. Thank God I had that tyvek suit too. Couldn't see anything through my glasses and thank goodness for my respirator as well.
Here are some pics. I was so tired I could hardly muster up the energy to take photos.
Here's the box I made out of R-10 2" foam board and spray foam. Used some screws to hold it in place. Currently it's sitting on some 2x3 strips in the hole in the ceiling and I'm going to button it up tomorrow with some spray foam and just sheetrock the hatch closed.
I just emptied the can of spray foam at the bottom of the box. Then I filled with cellulose and dense packed it by hand. I also dense packed the surrounding area a bit by hand since I didn't build a high enough dam and wanted to close it up anyways.
The bottom of this gable vent is just at 18". The other side was a bit higher.
Lordoftheflies
Active Member
I'm glad I cut the baffles just above where I wanted the insulation. Used it as a guide. My green painters tape on a mixing stick quickly became invisible with all that crazy dust. Now I get to wake up at 5:30am and return the machine damn it.
Lordoftheflies
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Lordoftheflies
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Ok so minor problem I put my hand down on the ceiling sheetrock awkardly whilst in the tyvek suit (no grip on the feet and slipped) and didn't think much of it.......but upon inspection I have a nasty crack in the ceiling in my bedroom.
One side of the crack it is clear that the sheetrock has been pushed down way past the flat plane - maybe about 1/4". As you can see in the pics it's not a small area I need to fix.
So the question is what's the best way to fix this without having 800lbs of cellulose fall down?
Initially I thought I might just get some Simpson Tie Plates and use a whole bunch of them flush to the ceiling. I could spread some mud over it and "try" my best to hide it but at the end of the day, I don't really care what it looks like - I just want it not to fail.
The crack is running parralel to the joists and is in between two joists. It runs about 20" long and is near the only light in the ceiling.
The other method I was thinking of was to use my car jack and a 2x4 with a piece of plywood screwed to the end of the 2x4 and press the damaged drywall back up. Once pushed back I'm not sure what else I can do because I don't really want to go back up into the attic and try and navigate back to the area of the crack - won't be able to see the joists. It will be a mess.
I was thinking I could either drill a small hole just big enough to slip a 1x3 across the crack and then zip a few screws to hold the drywall to the wood... The joist is at the bottom of the first picture where you can see a faint line in the drywall but it hasn't cracked all the way through.
The crack does not run a seam where two sheets of drywall meet as you can see there's no tape in the cracked area.
I'm a bit worried if I try to push it back in it might make the damage worse.
One side of the crack it is clear that the sheetrock has been pushed down way past the flat plane - maybe about 1/4". As you can see in the pics it's not a small area I need to fix.
So the question is what's the best way to fix this without having 800lbs of cellulose fall down?
Initially I thought I might just get some Simpson Tie Plates and use a whole bunch of them flush to the ceiling. I could spread some mud over it and "try" my best to hide it but at the end of the day, I don't really care what it looks like - I just want it not to fail.
The crack is running parralel to the joists and is in between two joists. It runs about 20" long and is near the only light in the ceiling.
The other method I was thinking of was to use my car jack and a 2x4 with a piece of plywood screwed to the end of the 2x4 and press the damaged drywall back up. Once pushed back I'm not sure what else I can do because I don't really want to go back up into the attic and try and navigate back to the area of the crack - won't be able to see the joists. It will be a mess.
I was thinking I could either drill a small hole just big enough to slip a 1x3 across the crack and then zip a few screws to hold the drywall to the wood... The joist is at the bottom of the first picture where you can see a faint line in the drywall but it hasn't cracked all the way through.
The crack does not run a seam where two sheets of drywall meet as you can see there's no tape in the cracked area.
I'm a bit worried if I try to push it back in it might make the damage worse.
Lordoftheflies
Active Member
Maybe I can drill the hole and use the 1x3 instead of a full sheet of plywood like in this video.
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Lordoftheflies
Active Member
I ended up using a 4" hole saw. Cut a hole in some 3/4 plywood, and some additional 1" holes for screws.
Then I used a 2x4 and wedged it between the plywood jig and another scrap on the floor. Used the $30 Milwaukee recessed light drill kit and cut out some 4" new pieces of round drywall.
Surprisingly very, very little insulation fell out of the hole. I ended up stuffing a microfiber towel up into the hole and spreading it out. Then I was able to put an 8" piece of plywood up into thehole, under the microfiber cloth and over the ceiling.
2 screws for each piece of plywood and 2 screws for the replacement round drywall pieces. It's not perfectly flat but close enough that I can fix it when I mud it.
Used some mesh tape and put the first coat of mud. Also put a new piece of drywall over the hatch.
Then I used a 2x4 and wedged it between the plywood jig and another scrap on the floor. Used the $30 Milwaukee recessed light drill kit and cut out some 4" new pieces of round drywall.
Surprisingly very, very little insulation fell out of the hole. I ended up stuffing a microfiber towel up into the hole and spreading it out. Then I was able to put an 8" piece of plywood up into thehole, under the microfiber cloth and over the ceiling.
2 screws for each piece of plywood and 2 screws for the replacement round drywall pieces. It's not perfectly flat but close enough that I can fix it when I mud it.
Used some mesh tape and put the first coat of mud. Also put a new piece of drywall over the hatch.
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