I’m getting ready to insulate my attic spaces. I’ve been told to use rafter venting (baffleing between the insulation and the roof sheathing). My rafters are 16 inch centers. The local home improvement store only carries 11 1/4 inch wide baffleing. Should I keep looking for baffleing that would fit better? Are there other solutions? What should I be aware of when installing?
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If you cant get the proper size, then use the smaller ones and just install more of them.
You also can use 1/4" plywood (or similar material like drywall) in place of these styrfoam baffles.
help me out here...how would drywall create the airchannel? And how would 2 small "propa-vents " work in one bay?
Have you ever actually done bay baffles?
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Cut up the styrofoam baffels lenghtwise so they will fit a larger space. i.e: 1 and 1/2 baffels per rafter bay or whatever. that's what I've done. I also can't see how drywall or 1/4 inch plywood would give your roof deck the necessary air space between it and the insulation unless you seperated it from the roof deck using strips of wood.
Correct me if I'm wrong but it sounds like the solution is common sense. I could just rip inexpensive material (plywood, sheething, paneling, etc...) and mount it on strips a reasonable short distance (1/2 inch) from the roofing sheething.
Rickjordan; You don't need correcting as your absolutely right.
glad to see some of us are thinking straight (you and me)
Duh , ya, just like you thought, you separate it from the roof deck using strips of wood ,...duh
Just use your noggin a bit.
cut some ledger strips, nail onto rafter sides, and cut the plywood or drywall into 14 -1/2" strips and nail to the ledgers.
Get it?
No I don't get it...why go thru all that labor when they are so cheap?
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Because he said he cant get the right size! So if ya cant get the right size ,improvise.
See, it's like this..the 11.25 wide are so ya can use two for trusses at 2' centers (the 22.5 inbetween) ONE is plenty for the 16 inch centers he has. Which is 14.5 between. There is no problem to solve. That is plenty to wide to keep the insul. vented.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Ding ding ding!
Sphere wins the prize!
The pre-formed baffles are not designed to fill the full width of the rafter bay.
Free beer? LOL
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Free beer AND personal bodyguard service at the next fest.<g>
Why only use 11.25" of the space when you can, by improvising,use the whole amount of 14.5 "
When it comes to providing a vent space cutting it down approx 25 % can make a huge difference.
You also say " that is plenty to keep the insul vented... huh! not true. Thats not what the space is for.
I am done with this..it is fine for soffit flow egress and ridge vent out flow..nuff said.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
oh sh!t,
Give yourself 1 1/2 inch airspace by securing spacers of the same on your rafters.
Then add some insulation for your money. Cut 1/2 inch foamboard like celotex which cuts easy to fit tight between the bays on the spacers.
Then don't use fiberglass batts unless you have to.
Foam or foamboard is a lot better insulation.
Hi ya RickJ, welcome to Breaktime.
Clicking here will take you to an old thread which discusses insulation and has some other links dealing with spray foam.
http://forums.taunton.com/tp-breaktime/messages?msg=46746.4
In the lower left hand of the screen, if you'll scroll down, you'll see a search bar and if you type in 'insulation' you'll end up getting a weeks worth of reading.
Cheers
Foamboard seems to have a higher R-value compared to the same thickness of fiberglass--I think 3" of foam is like R-15 and the same in fiberglass is R-11 or 13. But the foam is much more expensive--at least initially. Using your own spacers etc. would be OK in a small space, but would seem to be very time consuming for a whole attic.
There have been a number of threads here on Breaktime dealing with the cons of fiberglass and it's true R factor in real life that persuade me that the stuff is pretty much trash unless you have no other option.
It sounded to me as if the original poster was enlarging his living space which is such a laborious job that a small thing such as shooting nails would be minor for the benefit received.
But I've been wrong before.
Some guys cut 1 1/2 inch strips of insulation and use those instead.
After a tight shell if you want to insulate well it's the roof that demands the attention to get the most bang for the buck.
Seeing it's his own place extra effort is warranted since he's either the guy checking his house quality or he's doing the labor.
Sad but true. :o)