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Possible insulation and venting issues....where did my snow go?

Possible insulation and venting issues....where did my snow go?


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Old 02-15-16, 04:56 AM
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Possible insulation and venting issues....where did my snow go?

After our recent couple snowstorms, I noticed that my house is "different" (and not in a good way!) Two weeks after the storms most of my neighbors have at least some snow on their roofs. A few still have a perfect coating, some are spotty, but they all still have something...except me! Our snow cover was gone within a few days of the storms ending.

Ive always suspected our attic insulation/venting of not being the best (mostly because Ive seen this snow thing before). I would like to resolve the issue in the spring, Ive done some research and come up with the following:

We're lacking insulation and/or venting (or correct venting). So looking at venting:

For exhaust we have a full ridge vent and one 18"x18" gable vent. Im thinking step 1 is to try and close off the gable vent, to prevent it from "short circuiting" the whole venting system....the gable vent was there because the ridge vent wasnt a full length vent until we had the roof replaced a few years ago.

For intake, its hard to tell. When the house was vinyl sided, the siders used horizontal vinyl siding slipped into 2 aluminum channels so the joints were perpendicular to the walls of the house. Since these joints are sealed, Im sure it lets SOME air in, but since its not a simple perforated strip or round holes, I dont know how to determine just how much intake we have. I also dont know what the siding setup is covering (i.e. is there still wood soffit underneath or was that all removed?)

Insulation - fiberglass filling the joist cavities plus another layer. Plus another layer on top of that in certain spots that Ive added over the years. The fg itself is in OK condition, its just been moved, rolled up, unrolled, etc. Between adding electrical boxes, bathroom fan, etc. its just not a "clean" install anymore. There are also no baffles keeping insulation out of the eaves, but Ive done my best to try and pull the batts back enough to at least see sunlight through them.

Wrench in the works - we have HVAC ductwork up there. And I dont see any way (good OR bad) to move it. It runs perpendicular to the joists, and is insulated inside (ductboard?). Ive sealed all of the joints I can get to with mastic and mesh tape but thats the best I can do.

I see two options to fix it:

Remove all the fg, air seal like crazy, install baffles then blow in as much cellulose as I can. This is cheapest since my labor is "free" but it wont solve any lack of intake issues (if there is one), nor does it put the ductwork into the thermal envelope like is recommended.

Spray foam - Ive gotten a quote from a contractor that would use open cell foam on roof deck (7 inches, R30) and gable/knee walls (5 inches, R21). Im guessing this "fixes" venting issues because the attic becomes unvented and will fix the ductwork issue because they will be inside the thermal envelope. This is more expensive, but Im not averse to paying for it if its the better option.

Any advice/opinions/suggestions are welcome (I realize I posted this earlier this year but I didnt have much proof any of this was an issue until we finally got snow and I took a look at the venting setup myself)

Thanks in advance.

-Chris
 
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Old 02-15-16, 05:42 AM
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Hi Chris,
From your description it sounds like the soffits are not open. It wouldn't take a lot to keep that snow around, but closed soffits would surely warm the attic up. You will need to find a way to make that determination.

The foam on the bottom of the roof deck is not my first choice, of course we live up here in cold country so ac is half or less of our concern. In TX it is a better approach. I would just add a lot more insulation to the mechanicals up there and build a raised platform to provide space underneath for insulation and a convenient place to work on the ac when required. Insulating the attic floor and good ventilation is a well tested method and doesn't get in the way of future roof issues. Plus, you can go to r-60 on the attic floor where they are suggesting r-30. Code is r-38. And once the roof deck is insulated you have to at least partially condition the attic to prevent moisture problems.

Last, don't remove the gable vent. The whole short circuit theory was a fabrication from the roofing industry to see more ridge vents. If the gable vents are removed they cannot be counted as part of the ventilation. then, you need more ridge vents. The full explanation is a bit long, but leaving the gable vents in place actually increases the total air flow. You will be surprised when you hear what a spoof that short circuit excuse actually is. And I'm totally amazed it has gone unchallenged for so long.

Planning is good. I like your first approach, except for removing the gable vent.

Bud
 
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Old 02-15-16, 07:06 AM
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Thanks for the quick reply.

I hate to say it but it looks like Ill somehow have to figure out that venting! When we had the roof replaced the roofer said there was no problem with venting, after he cut the rest of the ridge vent he commented on how much hot air came out. But that doesn't mean its coming through the soffit, I suppose.

To add another wrench into the works, attached is a pic of the soffit area in the front of our house. Not much room to work with! Im not sure how I would handle it. Luckily the back of the house has a much more standard soffit, at least 1' wide.

 
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Old 02-15-16, 08:18 AM
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A couple of more pictures would help. One of the front from the front yard and then perhaps a selfie stick and a picture of what the soffit area looks like in the attic. People have been finding all kinds of way to take pictures of areas they can't reach.

If the soffit material in the front perforated. They make 2.5" wide perforated vent panels that might just fit up there.

Is that overhang ventilated, I see two black squares??

Bud
 
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Old 02-15-16, 08:28 AM
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Ill try to get more and better pics. Sorry I dont have a selfie stick though

The front soffit material is not perforated....its basically strips of siding cut and slid into siding channels (j-channels? not exactly sure the name). To the right of the part of the house in the pic is a cathedral ceiling with a steep slope. At that part of soffit, the roofer installed what you might be talking about...."Aluminum Under Eave Soffit Vent in White" by MasterFlow. Its about 2.75" wide and comes in 8 foot lengths. Im not sure he is still "in the game" but I might contact him and see if he could install it in the rest of the house too (or knows someone who can).

Ill get more front-of-house pics to help show what Im talking about.

As far as the overhang, no its not ventilated....those are just wire tie hangers used for xmas lighting.
 
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Old 02-15-16, 08:55 AM
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Good, the overhang should be air sealed and filled with insulation.

Even if there is some sort of opening under those strips it wouldn't allow much air flow covered as it is. AND the guy who put it up there should have known.

Bud
 
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Old 02-15-16, 09:33 AM
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More pics:

In this pic, the left side of the roof (2 full floors) is the short soffit in question



The left end of the short soffit area, showing the depth of the rest of the eave



Similar shot but better view of the end



I couldnt get any in-attic eave shots.....its too darn cold out right now! When I get a chance Ill try to shuffle into one of the joist cavities and snap a pic.
 
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Old 02-15-16, 01:15 PM
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BTW just went up into the attic quickly....towards the eaves I notice that the roofing nails have ice formed on them. And you can kind of see frost under the underside of the roof decking in the soffit areas....further up (towards the peak) the wood and nails are frost free.

On the back of the house its actually worse, presumably because thats the side that doesnt get sun most of the day.
 
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Old 02-15-16, 01:34 PM
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Does the back have soffit vents or more of the same issue where they are there but you don't know what is under them?

With the ice and frost, I would say there is no venting in those soffits. Not good.

Bud
 
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Old 02-15-16, 02:00 PM
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Back of house has same setup as front: siding over soffits without knowing what the siding is covering. At least on the back of the house there is 1 or 1.5' of soffit to work with....should be easy to install vents once I can get up there.

The front is the issue with the lack of overhang space.
 
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Old 02-16-16, 04:54 AM
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Thinking through this I have a couple questions:

Is the gable vent considered an intake or exhaust? There is only one so its not like there is cross ventilation so I wasn't sure.

The attic space is ~900 sq ft. using the 1 per 150 rule, I need 6 sq ft of venting. using the 60/40 rule that is 3.6 sq ft intake, 2.4 sq ft exhaust.

Now I cant reliably measure what I have in intake, but I *can* estimate my exhaust: ~40' long ridge vent. Figure 1.5" or 2" wide, that gives me a whopping 720-960sq in of exhaust (5 to 6.7 sq ft). Thats way too much even if my intake was perfect. The numbers say I should have about half that much.

So, how can you block off part of a ridge vent? And is that something I can/should do now to try and improve the situation?
 
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Old 02-16-16, 09:04 AM
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Ridge vents have a NFA rating less than the opening you are describing. A common number they advertise is 18 in² per linear foot of roof vent. That would give you your lower number of 720 in² or 5 ft². However, not all of the roof vents provide a clear path and that number is the exact opening without a reduction for bug screening. But even if we leave it at that, there are other concerns.

If the soffit vents are providing no intake, then that gable vent will be functioning as an intake vent. Obviously, for air to exit air must enter somewhere. But, the height difference between the middle of the gable vent and the ridge vent is not much and the air flow is directly proportional to that height. It would be providing some air flow but minimal and far from the eaves where the air is needed.

If the soffits are working, providing a reasonable amount of air, then that gable vent will be an exhaust vent.

For now, don't worry about the 60/40 balance as you need all of the venting you can get, especially at both soffits. Once all venting is working we can fine tune the high to low ratio, but it has a wide tolerance and the benefits or penalties for not being exact are so small they can only be identified with paper and pencil.

The ice and frost is a concern and a fan can be used to circulate air into the eaves to dry them out. Not sure I would leave just any fan up there running, but one rated for 24/7 should be ok.

A good day to dry it out if you are getting the warm/er weather we are getting.

Bud
 
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Old 02-16-16, 09:25 AM
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Thanks for the additional info.

I was thinking of a fan up there to help circulate....would something hanging from the gable vent and aimed out be helpful? Or should I get smaller fans and point them at the eaves?

I have a few circulation fans but I dont know if they are rated for extended use like that. If using a regular attic exhaust fan on the gable vent would work, that is far easier (there are indications that one was there before but was never replaced, so there is a covered junction box for power already where it needs to be)
 
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Old 02-16-16, 10:00 AM
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Difficult choice. Blowing air out the gable would mean the replacement air would need to enter the ridge, still some distance from the eaves. Using small fans blowing towards the eaves doesn't increase the air exchange. Circulating air out to the eaves is the highest priority. If you put a fan near the gable vent I would point it into the attic, just need to watch for rain being pulled in.

Both wouldn't hurt.

Bud
 
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Old 02-16-16, 10:26 AM
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A wacky idea:

Get a couple whole house fans (the ones that are meant for pulling air through a hallway ceiling), and stand one up on each side in the center of the attic, along with a cardboard, masonite, etc. panel the length of the attic sides to somewhat seal the fan and have it pull from the eaves into the attic, or even vice versa: aim the fans into the eaves with the spacer panels forming a "funnel" to make sure the air gets blown down through the eaves.

Obviously I cant seal it perfectly (joist cavities would still be open above the panel and insulated below the panel), but I would think the fans would be low enough to pull from the eaves and not the gable or the ridge
 
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Old 02-16-16, 10:59 AM
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Do we know that air can enter through the soffits?
Without air entering there would be no way to pull air out of the eaves. If you blow air into the eaves it would circulate back out. Two whole house fans seems like overkill. natural ventilation is powered by the difference in weight between warm and cold air, a couple of pascals, usually so slight that it can barely be detected. A whole house fan will be generating over a hundred pascals (a bit of a wild guess there), but a huge difference.

If you blow air into one eave at an angle so it creates a swirl around the perimeter of the attic, that will mix all of the attic air. You then need to encourage more ventilation to increase the exchange of outside to inside air.

Basically, with fan powered circulation you almost can't miss.

If you want to get innovative, if you draw air from the gable vent, via some makeshift ducting, and blow that around the perimeter, the extra air coming in will force more air out the ridge. If rain is a concern, then place a catch tub where it can collect. I have seen small swimming pools used to catch snow that was blowing in. But whatever small amount that enters it should evaporate easily.

Bud
 

Last edited by Bud9051; 02-16-16 at 11:00 AM. Reason: correction
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Old 02-16-16, 11:08 AM
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Thanks again. The whole house fan idea was because I can get them cheap (Lowes had 5700cfm fans for 35.00 each!!!), I actually bought them anyway just because they were so cheap. Can always return or resell.

Anyway....alternate plan is one of those air mover type fans at one end of the attic blowing towards the other, maybe on a slight angle to encourage a "swirl" like you mentioned. Possibly with a second opposite the first so it pulls that air and "turns" it around the gable wall and over to the front of the attic (you can see from my house front shot that the front part of the attic is not as long as the back, so the air might not swirl without some coaxing)
 
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Old 02-16-16, 12:59 PM
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I just went back into the attic and took a look around. It actually looks like most of the joist/rafter bays have dried themselves out. Where there looked to be moist wood yesterday its nice and dry, intact looking plywood (i.e. not dark stained, splintered, etc)

I suppose the high winds we've had today may have helped "push" air into the attic to help it dry out.

Im not going to treat it like an emergency, but Im not going to let it go. Ill be checking up there every few days during the winter and will have someone at least take a look at the soffits to see if we should add more venting (most likely yes), Im guessing that wont happen until spring (I doubt any roofer wants to be up on a ladder outside unless they absolutely have to!)

Thanks again for all of the help and feel free to add any info you might feel necessary. Once I get going with the project Im sure Ill be posting here again!
 
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Old 02-16-16, 01:21 PM
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You definitely want some low venting and spring will be much better. When you get to the balance question I can provide details as needed.

If the frost and ice on the nails returns, snap some pictures for the roofer to look at.

Bud
 
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Old 03-09-16, 10:04 AM
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Continuing the thread....now that today isnt freezing cold I was able to snap a pic of one of the rafter cavities. Im assuming the rest are the same/similar, this one was just the easiest to get to.

The shine of light is coming from one of the small round soffit vents that were already in place before the siding was installed over them. The rest of the soffit material is solid (i.e. no holes) and still in place, so we are probably low on intake air.

[ATTACH=CONFIG]63786[/ATTACH]

I plan on installing Accuvent baffles in each cavity, since it looks like I have good access to the top plate of the walls. Will be nice to be able to blow insulation into the cavity and have it insulate the top plate too.

Question - can I install the baffles now, before getting the venting taken care of? I havent found a roofer yet and wanted to get a jump on the work if I can, while its relatively warm out.

Thanks.

-Chris
 
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Old 03-09-16, 10:10 AM
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Installing baffles now should have no effect on roofing or installing the ventilation.

Bud
 
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Old 03-10-16, 06:16 AM
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Thanks! I think Ill be starting this weekend hopefully.

Should the baffle be sealed to the top plate/roof decking with anything like caulk, etc?
 
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Old 03-10-16, 06:35 AM
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I don't like tight spaces and just the thought of crawling down in there gives me the shivers. Never seen detailed caulking and just stapling them to the bottom of the roof should be fine. The flap at the end of the baffles prevents insulation from falling into the soffits and batt insulation can be added if more protection is needed.

Here is a link with illustrations.
http://www.dos.ny.gov/DCEA/pdf/Energ...insulation.pdf

Bud
 
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Old 03-14-16, 08:29 AM
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Got 2/3 done with adding baffles this weekend. Man what a pain in the everything kind of job.

As I shuffle around the attic I keep coming up with more questions:

1. Gable end walls - where the top cap meets a gable end (i.e. the exterior wall is parallel with the gable end), there is currently no insulation. What should I do for that? Just fill it with blown cellulose? Is it worth it to get Froth Pak and spray foam it myself?

2. "Knee" walls - where our cathedral ceiling goes over the living room, it intersects with a second story. If you can picture the angle, there is about half of a second story wall that is exposed to the outside and the other half is interior (basically the cathedral slices through it at an angle). In the attic they put up fiberglass insulation behind the interior side only. Is that correct? And if so, would I be better off leaving fiberglass or again, trying something like spray foam?

3. Walking platform - currently there is plywood attached to the top of the 2x8 joists, leaving about 7.5" for insulation. Since I want an R49 or even R60 install, should I be raising this up? There isnt a whole lot of platform area but it is there and we do use it (for storage mostly). If I should raise it up, can I leave the plywood in place, blow insulation under it, then build a shorter (Im thinking 2x6) raised platform on top of it, insulate in that and then add more plywood?

EDIT: 4. Blown in cellulose - is one brand better than another? The plan was to get the GreenFiber stuff from Lowes or HD, along with the free machine rental. Are there better alternatives out there, even if I had to pay for the machine rental?

Thanks in advance.

-Chris
 
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Old 03-14-16, 09:36 AM
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#1. Just fill it with blown cellulose? Yes
#2. "Knee" walls, Not following the description.
#3. Walking platform, The best approach is to remove the old and install the new ABOVE the total insulation. You want any moisture that makes its way through the ceiling to continue on into the attic air and be vented out. Leaving the old plywood in place offers a condensation point for that moisture movement. How much moisture, I can't say and I've see it done both ways and neither has (in my limited experience) posed a problem.
#4. Can't say one brand vs another. I would guess all will do well.

Bud
 
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Old 03-14-16, 09:41 AM
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Thanks for the quick reply!

As for the "knee" wall....in the pic below, note how the cathedral is over the right half of the house but you can see the second floor comes all the way to the front of the house. Where the cathedral is sloped it leaves some of the 2nd floor exposed to the exterior (its sided, etc) and some is under the cathedral so its interior.



Both the interior and exterior areas are accessible in the attic and they are vertical walls (knee walls? dunno). The area thats interior has fiberglass stapled to the sheating, the area thats exterior has nothing. Is that the correct way? Ill leave the fg in place if it is.

Thanks again.

-Chris
 
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Old 03-14-16, 10:03 AM
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It may be the term "kneewall" that is throwing me. Link below illustrates what a kneewall is. If this is just the partitioning between the house and cathedral ceiling area, then more is better, insulate both sides. But as long as one side is done and covers all common area, should be fine.

Two Ways to Insulate Attic Kneewalls - Fine Homebuilding Article

Bud
 
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Old 03-14-16, 12:15 PM
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Thanks, yet again! Ill snap a pic or two of what Im talking about (from inside and outside) when I get a chance.

Another question that popped into my head - all of the ductwork I have up there. We have a rigid main "trunk" that comes up from the basement into about the center of the attic, then travels around the inner perimeter of the attic. As it goes past each bedroom/bathroom, there are flex ducts that branch out to each supply register. The rigid trunk is insulated internally, the flex duct is 6" insulated duct.

When I blow insulation in, should I blow over the flex duct too? Im assuming I dont want to cover the trunk for condensation reasons, but wasnt sure about the flex (and if the flex would be crushed by the cellulose)

Thanks.

-Chris
 
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Old 03-14-16, 12:49 PM
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Typically, neither is insulated to the recommended levels.

Covering the main duct would only present a condensation issue on the exterior if the ducts are used for air conditioning. In the heating season those surfaces will not be colder than the attic roof deck nor exposed to humid air. If used for ac, then they need substantial insulation. If ac then we should determine the amount of inside insulation and calculate the dew point for attic air.

In either case, they need to have all seams and junctions air sealed, foil tape is a popular solution.

Flex ducts are often r-6 and should be buried in the cellulose where possible. They should also be supported to be as straight as possible.

Bud
 
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Old 03-14-16, 12:55 PM
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Yes, they are used for heat AND A/C. I will see if I can reach my hand in there to get an idea of the insulation (or maybe even a pic but I dont want to lose my phone ).

A while ago (years) I went around to each take off and made sure to seal it with mastic, heavy duty tie wraps and then real duct tape on the outside of the insulation. They are pretty air tight at this point, but that was before I wised up to needing them stretched as much as possible....a few of them have too much duct for the length of run so Ill be disconnecting those to shorten and reconnect

As far as the trunk itself, I just assumed I would NOT insulate over them, so as to avoid and condensation issues. I would build a dam on either side with something (rigid foam board, plywood, etc) to keep the cellulose off. But if we can calculate what needs to be on there I might be able to just blow over all of it instead.
 
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Old 03-14-16, 01:46 PM
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If we assume there is 1" duct board on the inside and give it a r-5 value, then you are losing a lot of energy, but the attic heat is keeping the metal duct surface warm, preventing attic moisture from condensing. Now, your attic may get to 140°, but that air and moisture originated from the outside. If we use 90° air at 90% RH it can cool down to 86° before it forms condensation. With your ac ducts filled with 60° air and r-5 inside and outside the mid point (the metal duct) would be half way inbetween, 75°. At just r-5 on the outside you would already have a problem. The way they get around this is to cover the ducts with a foil faced insulation so the attic air cannot filter through. If you want more insulation on the outside of those trunk lines, use an insulation enclosed in a plastic or foil.

Temperature, Dewpoint, and Relative Humidity Calculator

Bud
BTW, Duct tape gets an A+ for marketing and a D- for performance on heating systems .
 
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Old 03-14-16, 01:50 PM
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Agree on the duct tape, but I didnt use "Duct brand" duct tape....I used Nashua foil backed stuff, which IIRC is actually rated for duct use!

I will look into wrapping the ducts. Im not sure if Ive ever seen the duct wrap stuff readily available...do the big box stores have it or should I find a building supply?
 
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Old 03-14-16, 03:43 PM
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Although the foil faced bubble wrap is often used, it has a worse reputation than the duct tape . Here is one from HD.
60 sq. ft. R-6 Insulated Duct Wrap-INSWRP60 - The Home Depot
Taped and sealed it should keep the humid air away from the metal duct. Their web site wasn't very informative so check for application. There are others as well.

Bud
 
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Old 03-14-16, 06:23 PM
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Thanks (again!) for this. That's the one I stumbled onto and its readily available near me. Ill add it to the (growing) "to do before actually blowing in insulation" list!

Should the return air duct be wrapped as well (assuming it will be buried under cellulose)?
 
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Old 03-14-16, 07:57 PM
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Air sealing the return is equally important as the supply, but insulating is somewhat less. Doesn't hurt.

Bud
PS, we will expect pictures when done
 
  #36  
Old 03-15-16, 09:33 AM
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Timely development - just had an energy assessment done on our house. Turns out its pretty tight already but I did mention that I was looking to re-insulate with cellulose.

Wont go into exact numbers, but their price is basically 2x the price of materials if I did it myself.

They quoted me R-60, said they will blow over everything (including the ducts), etc. I said I would handle finishing the baffle installation, fiberglass removal and air sealing, all they need to do is blow in R-60 worth.

Im seriously considering it but was wondering - what kind of things should I ask/look out for? I know actual blown depth is a big deal....do i force them to put up rulers and leave them there so I can verify they blew enough in?
 
  #37  
Old 03-15-16, 10:10 AM
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I just went looking for a link that will help explain weight and density. I'm not a pro on cellulose, but it can be installed in a fluffy manner or very dense. I'll let you look, but the advice I have often heard is to count the bags.
Step One - Calculate Your Need | GreenFiber.com

As for energy assessments given by a contractor wanting to sell you something, you kind of have to be a bit more skeptical. If he keeps doing audits without writing a sale, they will replace him.

So what were the numbers, that will give us an idea as to how realistic their assessment was?

Did they do a blower door test and what was the CFM50 number. Add your house volume and we can judge how tight it is.

Did they do a duct leakage test, now required where ducts are outside the envelope.

Did they break down the heat loss per similar surfaces, like windows, walls, ceiling, and air leakage. Any advice other than the product they sell?

As for the price being twice what you could buy the materials for, the more common comment is a contractor can do the job for about the same price you would pay for materials. I would seek another bid on the cellulose.

Bud
 
  #38  
Old 03-15-16, 10:35 AM
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The final report is supposed to be emailed to me. They said the expected CFM was 2100 and actual was 1980. Wont be positive that is CFM50 numbers until I get the report. The house volume will be on there too. They did mention all of these terms and numbers to me, so they were at least giving an illusion of being forthcoming.

No duct leakage test...I really wanted one but they wanted the A/C to run so they could determine what the ductwork would flow. Its too cold out up here so the A/C never ramped up to something higher than stage 1 (5 stage AC) so of course the airflow indicated "too low" for them to test leakage.

I got into a long conversation with the tech about this because my system is made to run at low speed (modulated gas heating and variable speed cooling) and he said they are running into that more but their energy audit rules state they need to see 350cfm airflow before they can test leakage....mine was running about 280cfm since it was stuck in first stage.

There was plenty of advice given. It was most definitely not a sales call. The quote for insulation was more of a "I can quote you if you want" and that was the only thing the priced out. There was no "well you need to do X, Y, Z". Its a program subsidized by the utility companies in my state, youd figure they wouldnt want to risk a somewhat steady income stream by loading people up to buy stuff they dont need.

As far as their cost....Ill definitely look around to see if I can someone to do it for my cost. Usually thats not feasible in our area (Northeast, where everything is expensive everywhere) but Ill try. Im still leaning towards doing it myself anyway, the more I think about it, that way I can take my time and make sure its the way I want it vs. someone dumping and running.
 
  #39  
Old 03-15-16, 12:55 PM
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A target of 2,100 cfm would typically indicate a 2,200 ft² home with a volume of 18,000 ft³. Coming in below that is good, but there is still more to be sealed. If that is based upon the old 0.35 ACH then the target is where no additional ventilation is needed. Modern thinking is to continue sealing and add the right amount of ventilation. Then you know where the air is coming from and nor just leaking through the walls. Reduces energy costs and provides a higher air quality.

Sounds like they wanted to test just the leakage to the outside where a full duct leakage test measures all duct leakage. I'm not sure what your codes require, but from a trouble shooting approach, I like to know the total leakage.

Good that it wasn't just a sales pitch. I pulled up this calculator, looks interesting. See how that compares with their quote. BTW, R-60 is a lot of insulation.
R60 Insulation Costs - 2016 R60 Insulation Prices, Options and Installation Costs for Your Area - Homewyse.com

Bud
 
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Old 03-15-16, 01:22 PM
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The zone we're in is an R49-R60 recommendation. I was planning on doing R49 myself, they quoted R60....just to make sure it was apples to apples I increased my material cost to reflect what it would cost me to do R60 myself.

According to the calculator you linked to, their "before rebate" price is actually towards the low end. They are giving a 1.00/sq ft mail in rebate and my job is 993 sq ft. The calculator does seem to overestimate the cost of materials somewhat, no matter what quality level you choose.
 
 

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