Attic access to add insulation: truss beams every 18 inches

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Weathering
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Attic access to add insulation: truss beams every 18 inches

Post by Weathering »

I've been considering air-sealing and then adding insulation to my attic as a DIY. This is mainly because I don't think a contractor could get all the way through my attic. It is only 6' tall at the center, about 50' long, and has two L-shaped wings, each 25' long. But the main obstacles are the vertical truss studs/beams every 18" across the attic (some with plumbing going between and others with flexible ducts taking up the entire opening). This will require someone to twist, step over, and duck under all at once - many times before getting to the far end of the attic. In total, my attic is 1650 sq ft.

As DIY project, I would just need to commit myself to lots of false starts and excessive trips up/down from the attic crawl space as I confirm what I can/can't do. I could get that done in 1 day for aid-sealing and 1 day for added insulation (although I am starting to think about double-wrapping the flexible ducts rather than just burying them in blown-in insulation, so that would take another 1/2 day).

This is all a long way of saying, do you think there are insulation contractors who would not be phased by an attic such as mine? And would quote me the type of prices I'm hearing others, with more open attics, getting quoted (e.g., $2,500 for air-sealing and additional blown-in insulation)?
Big Dog
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Re: Attic access to add insulation: truss beams every 18 inches

Post by Big Dog »

can't comment on price, but I can assure you taht some contractor will take the job.

(we replaced out HVAC ducts a couple of years ago, and it was a really tight squeeze to the front of the house via the attic. Two guys alternated crawling and twisting thru for 3+ days. )
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Sandtrap
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Re: Attic access to add insulation: truss beams every 18 inches

Post by Sandtrap »

Weathering wrote: Thu Aug 11, 2022 6:55 pm I've been considering air-sealing and then adding insulation to my attic as a DIY. This is mainly because I don't think a contractor could get all the way through my attic. It is only 6' tall at the center, about 50' long, and has two L-shaped wings, each 25' long. But the main obstacles are the vertical truss studs/beams every 18" across the attic (some with plumbing going between and others with flexible ducts taking up the entire opening). This will require someone to twist, step over, and duck under all at once - many times before getting to the far end of the attic. In total, my attic is 1650 sq ft.

As DIY project, I would just need to commit myself to lots of false starts and excessive trips up/down from the attic crawl space as I confirm what I can/can't do. I could get that done in 1 day for aid-sealing and 1 day for added insulation (although I am starting to think about double-wrapping the flexible ducts rather than just burying them in blown-in insulation, so that would take another 1/2 day).

This is all a long way of saying, do you think there are insulation contractors who would not be phased by an attic such as mine? And would quote me the type of prices I'm hearing others, with more open attics, getting quoted (e.g., $2,500 for air-sealing and additional blown-in insulation)?
It depends on what you have now and what insulation you want put in and how.
ie
blown in or solid bats layed between truss joists
treated cellulose loose blown in or other synthetic (not itchy no fiberglass) etc
add to existing or what
what else needs to be done, needed or additional add ons
access (huge) logistics

Reputable licensed contractors do this all day all year round.
What you may think of as difficult is just another attic another day.

Suggest a minimum of 3 written quotes following on sit visit and on site inspectio (a must).
from reputable licensed insured full time experienced companies that specifically do this type of service.

J🌴
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123
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Re: Attic access to add insulation: truss beams every 18 inches

Post by 123 »

Weathering wrote: Thu Aug 11, 2022 6:55 pm ...do you think there are insulation contractors who would not be phased by an attic such as mine?...
The contractor likely isn't the one doing the work, it will be his/her worker bees. Your attic situation is likely not unique, the contractor will quote a price, if you tell him in advance how complex you believe the situation is that price will be higher.
The closest helping hand is at the end of your own arm.
ralph124cf
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Re: Attic access to add insulation: truss beams every 18 inches

Post by ralph124cf »

If you don't want to do it yourself,(I certainly would not) be sure to tell the contractor that you will personally crawl up there to inspect the work. Then do so. You will almost certainly find some incorrectly done work. Get the contractors people to do it right. Inspect it yourself again, until you are satisfied.

Ralph
tortoise84
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Re: Attic access to add insulation: truss beams every 18 inches

Post by tortoise84 »

Yeah I'm doing this DIY too. I also put up a radiant barrier which reduced peak attic air temps from around 105 to 100, but it also seems to retain heat well into the evening, so I can't really recommend it. And I'm now in the process of double wrapping my flex ducts with regular R-13 Kraft faced wall insulation, which has dropped my AC supply outlet temps by a noticeable 4F.

A contractor should know how to get around any attic. But if you're going to DIY, is there any sort of catwalk perpendicular to your trusses? If not, perhaps you could use 1'x4' pieces of plywood to help you move around and stand on. Wear a hardhat to protect your head, especially from nails coming through the roof deck. An insulation blowing machine should throw the insulation from the tube a few feet and you can push it the rest of the way into the corners with a broom or something.

This is my attic. Trusses are spaced at 24" and there is a catwalk made of 2"x4", but I covered it with fiberglass so that I know where it is in the future. The rest is blown in cellulose because it's cheaper. This definitely was not a single day project for me. I can only go up there for a few hours each day in the morning, before it gets too hot. So this project has been ongoing for a couple of months already.

Image
peke9898
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Re: Attic access to add insulation: truss beams every 18 inches

Post by peke9898 »

Have you had no-cost energy audit for your house offered by your electric company? I do not know if it is offered by all electric companies. They usually give 75% off for attic insulation.
LISD
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Re: Attic access to add insulation: truss beams every 18 inches

Post by LISD »

tortoise84 wrote: Sat Aug 13, 2022 6:19 am Yeah I'm doing this DIY too. I also put up a radiant barrier which reduced peak attic air temps from around 105 to 100, but it also seems to retain heat well into the evening, so I can't really recommend it. And I'm now in the process of double wrapping my flex ducts with regular R-13 Kraft faced wall insulation, which has dropped my AC supply outlet temps by a noticeable 4F.

A contractor should know how to get around any attic. But if you're going to DIY, is there any sort of catwalk perpendicular to your trusses? If not, perhaps you could use 1'x4' pieces of plywood to help you move around and stand on. Wear a hardhat to protect your head, especially from nails coming through the roof deck. An insulation blowing machine should throw the insulation from the tube a few feet and you can push it the rest of the way into the corners with a broom or something.

This is my attic. Trusses are spaced at 24" and there is a catwalk made of 2"x4", but I covered it with fiberglass so that I know where it is in the future. The rest is blown in cellulose because it's cheaper. This definitely was not a single day project for me. I can only go up there for a few hours each day in the morning, before it gets too hot. So this project has been ongoing for a couple of months already.

Image
Interesting about the improved A/C - I might try that.

Does your radiant barrier have an air gap between the roof (ceiling of the attic) and itself? I've been researching this - thinking of putting the double-bubble wrap with foil on both sides in the roof of my garage (reflectix). The manufacturer says air gaps are a must. But your's may not have the bubble insulation, only the foil? So I'm not sure. But my guess is that if it's touching the roof, then the heat will be conducted through the foil, and the radiant benefit will be minimal.

To the OP: you will be able to find a contractor. I am getting quotes now. One contractor said that my attic is a dream, lots of vertical space.
Sometimes they have 1400 ft2 houses with no more than 2 ft of vertical clearance. They literally crawl around the entire attic. To give you an idea of cost (at least where I am): a 2300 ft2 house = $12k to remove old insulation, clean the attic, seal the ceiling (floor of the attic), install R30, rodent proof, and insulate 5 skylights. I consider that a high cost (I think I can do better if I look hard enough). You can probably scale that to your house ft2 to get a rough cost for you.
tortoise84
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Re: Attic access to add insulation: truss beams every 18 inches

Post by tortoise84 »

LISD wrote: Sat Aug 13, 2022 7:30 pm Interesting about the improved A/C - I might try that.

Does your radiant barrier have an air gap between the roof (ceiling of the attic) and itself? I've been researching this - thinking of putting the double-bubble wrap with foil on both sides in the roof of my garage (reflectix). The manufacturer says air gaps are a must. But your's may not have the bubble insulation, only the foil? So I'm not sure. But my guess is that if it's touching the roof, then the heat will be conducted through the foil, and the radiant benefit will be minimal.
Yep I did leave an airgap of 2-3.5" below the roof deck, and mine was foil only. The reason I didn't get the Reflectix with bubble wrap was the cost. I needed 1500 sq ft so I got foil only radiant barrier on eBay for $220.
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Sandtrap
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Re: Attic access to add insulation: truss beams every 18 inches

Post by Sandtrap »

tortoise84 wrote: Sat Aug 13, 2022 6:19 am Yeah I'm doing this DIY too. I also put up a radiant barrier which reduced peak attic air temps from around 105 to 100, but it also seems to retain heat well into the evening, so I can't really recommend it. And I'm now in the process of double wrapping my flex ducts with regular R-13 Kraft faced wall insulation, which has dropped my AC supply outlet temps by a noticeable 4F.

A contractor should know how to get around any attic. But if you're going to DIY, is there any sort of catwalk perpendicular to your trusses? If not, perhaps you could use 1'x4' pieces of plywood to help you move around and stand on. Wear a hardhat to protect your head, especially from nails coming through the roof deck. An insulation blowing machine should throw the insulation from the tube a few feet and you can push it the rest of the way into the corners with a broom or something.

This is my attic. Trusses are spaced at 24" and there is a catwalk made of 2"x4", but I covered it with fiberglass so that I know where it is in the future. The rest is blown in cellulose because it's cheaper. This definitely was not a single day project for me. I can only go up there for a few hours each day in the morning, before it gets too hot. So this project has been ongoing for a couple of months already.

Image
Great job!

I've never heard of wrapping the flex ducks.
Must be tough as access is hard and the ducks are so floppy.
**Will just the tape keep the wrap on the ducts?

**Did you blow in additional insulation with a machine or just brought up the compressed cubes and then spread it yourself or did you use a machine, or contractor?

** How did you install the radiant barrier?
Was it difficult with the ducks in the way?

Of course, disposable overalls, gloves, infamous N95 breathing mask used by trades forever or equiv, head protection from the dreaded roofing and framing nails. . etc.

Again, good job.
Very ambitious.
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Valuethinker
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Re: Attic access to add insulation: truss beams every 18 inches

Post by Valuethinker »

tortoise84 wrote: Sat Aug 13, 2022 6:19 am

A contractor should know how to get around any attic. But if you're going to DIY, is there any sort of catwalk perpendicular to your trusses? If not, perhaps you could use 1'x4' pieces of plywood to help you move around and stand on. Wear a hardhat to protect your head, especially from nails coming through the roof deck. An insulation blowing machine should throw the insulation from the tube a few feet and you can push it the rest of the way into the corners with a broom or something.
Nowadays the plumbers here (UK) all wear knee and elbow pads it seems. Saves on the arthritis later they tell me.
tortoise84
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Re: Attic access to add insulation: truss beams every 18 inches

Post by tortoise84 »

Sandtrap wrote: Sun Aug 14, 2022 7:22 am Great job!

I've never heard of wrapping the flex ducks.
Must be tough as access is hard and the ducks are so floppy.
**Will just the tape keep the wrap on the ducts?

**Did you blow in additional insulation with a machine or just brought up the compressed cubes and then spread it yourself or did you use a machine, or contractor?

** How did you install the radiant barrier?
Was it difficult with the ducks in the way?

Of course, disposable overalls, gloves, infamous N95 breathing mask used by trades forever or equiv, head protection from the dreaded roofing and framing nails. . etc.

Again, good job.
Very ambitious.
j :D
Thanks. I haven't heard of anyone else double wrapping flex ducts either, so it was sort of just an experimental idea. I have heard of burying the ductwork in the insulation, but the concern is condensation forming on the ductwork and messing up the insulation, so this is only recommended in dry climates. Reference article. My ductwork is also strapped to the trusses so it's too high to bury, and I'm in hot and humid South Florida.

Another option is using closed cell spray foam on the ductwork because this also forms a vapor barrier. Reference link. However, this is expensive and not really within my DIY capabilities.

So I came up with the idea of wrapping the flex ducts with Kraft faced insulation which will hopefully provide enough of a vapor barrier to prevent condensation on the ductwork. A roll of R-13 made for walls is also much cheaper than specific duct insulation at $23 for a 15" x 32' x 3.5" thick roll (40 sq ft).

The three pieces of 48mm wide Nashua Foil-Scrim-Kraft tape across the 15" wide seam in the insulation as shown in my photo were actually not enough to hold it together. So I went back and used five pieces of 72mm wide FSK tape to cover most of the 15" seam, and it seems to be holding up fine. But I'll also go back and tie some string around it for the 'belt and suspenders' approach.

I broke up the cellulose insulation myself by putting it in an 18 gal Sterilite tote and mixing it with an 30" grout mixer. Because I only worked a few hours each day, I couldn't really rent a machine for that long.

The radiant barrier wasn't too hard to just staple between the rafters. I cut 6 ft lengths beforehand so there wouldn't be too much draping down to handle since I was working by myself. The duct in my photo is actually the only one close to the roof. The rest are down low. The only hard part was getting out to the eaves, so I used a piece of OSB across the trusses and had to get on my back or belly.
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