Various questions about adding r-30 rolls over existing blown in and how will I get around up there after it’s installed?
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| It’s a 28 x 24 attic with an air handler right in the middle of it, along with it’s intake and output venting.
Also, the interior gable end is the back of a cathedral ceiling for the rest of the ranch house. As I want to do this right, being that it will be hard to work up there afterwards, these are my questions: 1. Do I roll the R-30 over the air handler and it’s various ventwork, or (as was suggested) just over it’s ventwork. The handler and the ventwork are now covered with foil backed wrapping. 2. The insulated gable end has lost about 30% of its vertically applied batting, R-19 I think. It seems to been applied kind of piecemeal in many pieces. I want to add more insulation there. Can I use the unfaced rolls I’ve already bought, or do I need to have an insulation barrier (faced rolls or batts). There isn’t enough height (or desire) to construct any sort of framework there. Whatever I do there will have to be done before I start rolling the floor inslation out. 3. How do I handle all the wiring that is running along the top of the horizontal bottoms of the 2×4’s of the trusses? Just roll over them? 4. Will I be able to get around up there in the future? Should I leave planking around the air handler at least in case it requires service in the future? How do people get around up there when you cant see the planking? It would seem that you shouldn’t compress the new 9-10″ of insulation by laying planks over it. I’m installing attic baffles at least where the soffit vents are. I basically want to consider everything that I might need to do in the future as it seems I will in effect be painting myself into the middle as far as getting around up there after the insulation is installed. Thanks
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Replies
Couple of things first. What's your goal? Are you trying to stop drafts or lower your electric bill? If this is not the whole attic space you're insulating what do you plan to do to bring the balance up to the same R value?
The goal is to lower the electric bill and be more comfortable.
I will be adding r-30 rolls to the entire 24 x 28 attic, over what's in there now, not just in the area in the photo. I put that up just as a representation of the attic as it is now.
The cathedral ceiling end, which has some loosely attached verticle batts needs to be beefed up because I am sure a lot of the heat is escaping from the upper portion of the heated side of the ceiling into the attic.
I'm just wondering if the current batts (with vapor barrier backing) will be enough vapor barrier so that I can somehow use unbacked r-30 rolls to add what it needs.
I don't notice any drafts.
I just looked at the photo again. You can see that the pink stuff was kind of crammed in between the truss. The drywall to the finished area is attached directly to the truss, whis a sure fire heat loss. The more I look at that end of the attic (siding against the heated cath ceiling), the more I think I can gain in saving heat and money, as long as I get it done correctly. (re vapor barriers and enough r-value).
The whole 9 yards
Move all that blown-in out of the way so that you can seal all the various holes, crack, openings, and etc. in the attic floor. You want to minimize air leakage from the house into the attic. Then, build a raised platform for the air handler and make a walkway so you can get over there from the attic hatch without walking on/thru insulation. Remove whatever covering is on the air handler and ducts and seal all the joints and seams with duct mastic. Then install insulation on the ducts and the air handler. Build an insulated cover over the attic hatch. Then blow in more insulation (probably cellulose) on top of what's there.
It might be easier to have an insulation contractor do all of this. Get the right crew, one that does weatherization. They know the drill and all the tricks.
Yeah, definitely blown in cells is better than fiberglass batts. You'd never get the fiberglass down flat and even, and fiberglass is not a very effective insulation when the back is open to the air anyway.
The problem is that you can't insulate part of an attic and expect enery savings. You'd be far better off to do as others have suggested and air seal first and then blow in loose fill. You'll also need a plan to insulate the cathederal area as well. For a vapor barrier I'd be inclined to paint the ceilings with a vapor retarding paint.
Well, you CAN insulate part and have an energy savings, just not nearly as much. The poorly-insulated part is effectively a window.
I cannot do blow-in. This is a one man project and I have more time than money.
The air handler is immediately adjacent to the scuttle and I can reach the filfter while standing on the ladder when it's under the scuttle. So I'm just going to put planking down along side the unit and cover it up with the rolls.
My biggest concern now is to decide which material(s) to use between the unconditioned attic and the conditioned living room behind the attic gable. I think it's the summer cooling which is suffering the most because the heat in the attic was intense. This should be somewhat mitigated now as I have added soffit vents...there were none before.
I'm also going to install attic baffles between every truss instead on just at the soffits. That should increase the ventilation up towards it's roof vent.
So.....would rigid foam be something I should consider using at the gable end?
Do you use one particular material vs another when you're trying to keep heat out vs when you're trying to keep heat in?
Of course, now I'm not so sure how hot it will get up there in the summer after putting soffit vents in.
I added a photo of the gable end showing where the verticle batts have fallen down, probably from the heat or moisture. You can see the end of the exposed beam and some sort of framework they put in, maybe to attach the insulation to. You can't really see it but a large air return is located under the beam, sitting on the trusses.
Where should the vapor barrier be once whatever insulation is installed.
The other photo is the existing wrap of the air handler and it's ventwork. It looks to be totally covered in its (removeable) wrapping.
Trust me, you do not want to use batts up there. This appears to be a 4/12 or 5/12 roof, very similar to mine, and it's damn well impossible to move around up there. You'll never get the insulation to tighly fit around the trusses, and dragging batts back into the corners will be an extremely frustrating process.
But regardless, before you start build a catwalk down the length of the ceiling, from one gable to the other. This would be a pair of 2x6s or 2x8s stood on edge and toe-screwed to the joists, with 1/2" plywood or OSB sections lightly tacked (ie easily removed) to the 2xs. Before you do the rest, stuff the area under the catwalk with insulation.
Also build a tall wall around the scuttle, though do it in two "tiers", the first adding 6" or so directly around the scuttle, and the second adding at least another 6" (12" or more total) only set back from the scuttle by 6-12 inches. Don't install the second until you're nearly done.
insulating the gable is my biggest concern right now.
Right now, since it's starting to get cold and the heat pump is running, my main concern is getting that gable end insulated.
What's on there now is a mish mash. You can see from the photo it is seriously lacking insulating protection. Anything would be an improvement at this point.
It seems that if I could possibly install a layer of rigid foam of some composition against the heated side it would at least give me 1) a clean flush surface to attach some r-30 to later and 2) provide a barrier that would prevent the fierce attic heat from getting into the living room cath. ceiling during the summer (if what I've read is true about FG not providing much protection from radiant heat, like from the roof).
What I am not sure of is what the vapor barrier should consist of and if I can buy some rigid foam that would include a vapor barrier already built in.
Blown in cellulose if the only way to go. But if you have lots of time, then you would be better off pulling back all the current loose file and sealing all penetrations and all of the joints where walls meet ceilings. Probably take you a couple of weekends and your knees and back will scream at you but doing the air sealing will pay more back than anything you do with insulation.
OK, lets go back a few steps here...
...the heat in the attic was intense. This should be somewhat mitigated now as I have added soffit vents...
Um, no. Ventalation does exactly ONE thing: Remove moisture from the underside of your roof deck. It will not cool it in any appreciable way, nor should it. As a matter of fact, if you have too much ventaltion, you can be sucking air that you paid good money to heat or cool out of your house. Sometimes you can even blow bad air back into the house from above.
You do have the right idea though, using chute baffles to allow air flow from soffit vents into the attic space. Keep sthat plywood nice and dry.
Do you use one particular material vs another when you're trying to keep heat out vs when you're trying to keep heat in?
Not unless you live in the south, which brings us to a BIG issue:
Where should the vapor barrier be once whatever insulation is installed.
That question can only be answered after you fill in the blank:
"I went to http://www.energystar.gov/index.cfm?c=home_sealing.hm_improvement_insulation_table and found that I live in Zone _______. "
So.....would rigid foam be something I should consider using at the gable end?
Sure, while it's easier to handle it's alot more expensive than blown in cells. Which, you can do yourself - you can rent out the machine to do it have have one of your dumb friends fill the machine while he drinks your beer.
Thanks paulcp. You've actually answered some questions.
I live in an uppermost county of Zone 4. Just south of Zone 5.
As an update: While I was up there installing ONE baffle today (in an hour or so, lots of prep moving planks etc) I became completely discouraged when I saw 1) how really difficult it is to get to the edge of a 12:4 sloped roof , and 2) how much blown in insulation has been removed at at least one corner of the attic.
What hurts is the realization that I really can't / shouldn't use rolls now. I discovered other problems as well...it seems that the drop ceiling over the fridge and the kitchen cabinets along the back exterior wall just look like troughs or voids....right at the hardest places to get to.
This is all making me think that blow-in is the only realistic way I can go, reluctantly as a hire-out as my daily duties require me to assist someone with special needs every few hours. And to do this myself (or even with the help of a beer swilling buddy) is looking unfeasible.
I looked at some you tube videos of the range that the blow-in can reach (10 feet or so) so I think at least a contractor could do it.
My issue NOW (it changes daily) is to decide how much prep work I can do myself beforehand to both insure an effective job as well as not having to pay an insulator to do something I might be able to pull off myself beforehand.
Such as at least installing the rigid foam along the gable end (see photo). I'm pretty sure once I know the right product to put up I could at least get that done. The additional insulation needed on the colder side is more iffy. I've seen a few schemes to support batts or rolls (with chicken wire or tyvek) but I'm not sure if I want to do that or leave it to the contractor.
There is at least one other spot where warm air is somehow escaping into the roof as I recall seeing the snow melting too quickly in a portion of the roof behind the indented front porch, which is adjacent to the blown out insulation I found in a corner. Haven't figured that one out yet.
Wow, long post.
Anyway, I guess for now I could fix the gable which has little effective insulation and investigate the melting snow issue in a portion of the cathedral ceiling area (behind the front porch).
Then maybe get some bids.
Question: How do they prevent the blow in from filling the soffits..when there are no baffles installed. Do they have to install baffles between each joist?
edit: Yet somehow I might be able to do the blown in with a buddy....once all the prep work has been done.
Lots to cover
Those dropped areas in the kitchen might be major air leaks. They definitely need a professional to look at them and do whatever air sealing or baffling is needed.
Baffles need to be installed in every rafter bay at the eave. That keeps the insulation from spilling out and cover the vent openings. That has to be done right. Yes, it is hard to get out there with a 4:12 pitch. Insulators do it every day, they have tricks.
The wall areas might best be done with batts between the studs followed by rigid insulation continuous over the studs, with joints taped and edges foamed. Fiberglass will do OK if sealed in on all 6 sides.
Cellulose will do somewhat better as loose fill than blown fiberglass.
Finding a competent insulator is the hard part....
Does every rafter bay require a baffle, or only those which contain a soffit vent?
If they dont require baffles between the trusses without soffit vents, how do you prevent the soffits (the unvented ones) from filling up?
There are 3 soffit vents in the 24 feet of attic length, along each front and back wall.
I could install the 6 baffle vents at the vented spaces, but to do all 22 baffles would be a real ordeal.
As long as I know I won't have to roll out batts for the entire 700 sf, I might be able to do this with help for the blowing in.
I came up with an alternative way to do the baffles that worked pretty well. I have a bunch of corrugated plastic political signs in the garage from when I ran for office about 15 years back. I bought a bunch 8-foot 1x2s, cut them to about 7 feet (after I found that was the longest I could manage in the attic) then built a jig so that I could stand two 1x2s on their narrow edge and staple a sign to them. The 1x2 were spaced to fit between rafters, and the sign was cut to stick out on each side about 1.5 inches, though the very end 4 inches or so were trimmed close to the sticks.
I forget what the actual dimensions were, but I think about 5 feet of sign, and another two feet of the sticks sticking out from one end.
You get one of these up into the attic, stick the end in between the rafters so the very end of the gizmo rests on the plate, lift the stick ends up parallel to the rafters, and tack the ends in place with drywall screws. Hard to describe, but it works real slick, and you can put a baffle in in about 2 minutes (not counting crawling out there, dragging the thing, and getting yourself into position).
That's a great idea for the baffles. I found some foam ones that are precut and pre creased so the soffit end can be folded to form fit the shape/ángle needed at the wall end.
If I can get the 'pusher' end to fit tight enough I think I can preglue the furthest ends of the baffle and just staple the reachable parts. Heck. maybe even a rake riding on some sort of sled would work if I could get the folds stapled in the right position before I push them into place. The baffles are 24" wide.
In theory it sounds good, hahahahahaha
They should sell something like that.
I've thought of a foldable version of my scheme, with a metal frame (similar to metal studs, but thinner), and Tyvek (pulled tight when you unfold the thing) vs the plastic signs.
I tried using the foam baffles and found them pretty much impossible to install, plus they weren't generally long enough.
What hurts is the realization that I really can't / shouldn't use rolls now.
Yep, that's what I was trying to tell you.
I discovered other problems as well...it seems that the drop ceiling over the fridge and the kitchen cabinets along the back exterior wall just look like troughs or voids....right at the hardest places to get to.
I know it well. You need to attempt to seal the area, since the stud cavities are exposed, allowing warm air to rise out of them. This is bad on the outside wall, but worse if you have the same sort of soffit on any inside walls. I've done several things with these, mostly involving fitting pieces of drywall in between the joists, laying on the top plate on the far end, just held in place by gravity and maybe a few dabs of construction adhesive. Then, if you have any strength left, attempt to foam the joints.