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Decision time: hire a pro or DIY for attic insulation

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  #1  
Old 10-24-16, 01:18 PM
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Decision time: hire a pro or DIY for attic insulation

Hi all,

So, I finally got into my lower attic (1950s/60s era split level home in southern 'north jersey')... I need to figure out the cost of doing this myself vs a quote I have for having a pro do the (blown in) insulation for me (I know that will cost about $1,000)

Before I can figure that out, I have to decide, if I DIY--what approach I will use? I had a long thread with some very useful suggestions on this site (HERE), but now I have pictures and measurements and am hoping to really home in on my preferred approach--whatever that is

For starters, let me describe the layout. This is technically the 'lower attic', accessible via an access panel in a closet (on the wall). The framing is 2x6, and I have to admit: I dont understand why its framed the way it is. Some gaps are 14.5", some are 15.25". There is one section that is 8". The framing changes direction in one area

The insulation that's there (faced, missing in a few places) has fallen down to 2". There is a section of roof over the porch that is open to the attic (no insulation) and there is a roof on the back over a 3 season room that also has no insulation now (should there be?). Do I need to worry about using faced insulation in the places where the insulation is missing?

Overall, not counting the two uninsulated roofs I just described, its a square 22.5'x28. (630 sq ft). I also have about 32 sq ft of wall that needs insulation (2x4 construction).

So, my questions:
  1. I know I can add R-11 unfaced batts on top of the existing stuff. Given the average of 14.5" spacing, can I fit 15" wide insulation there, or will I need to trim? I really dont want to trim every piece
  2. If I opt for blown in insulation, I know I need to get baffles for soffit vents, can lights, etc. What about that front porch roof? is there any problem insulating it--or should i put a baffle around that too?
  3. If I go with fiberglass batts, sounds like I need 630 sq ft R11 to get me to R-19, then I will need another 630 sq ft of R30 to get me to R49?
  4. If I go with DIY blown in insulation, I am not sure how many packages of GreenFiber I would need? Assuming I need R-49, and if I read the instructions correctly, you get 12sq ft per bag, I am looking at 52 bags? We are up to $600+ then
  5. Do I need 'attic' insulation, or is any unfaced insulation sufficient?


The pics:
I saw blocked soffit vents:



This shows most of the attic--note how the framing changes direction:



This shows how insulation has 'fallen':



This shows the can lights I am dealing with (IC rated, LED lamps):


This shows the front porch (uninsulated):



As always, thanks for your comments. I learn so much here!
 
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  #2  
Old 10-24-16, 02:06 PM
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basically trying to see exactly what my materials list would be, thereby getting a materials cost. If I did the math right, DIY blown in would run me approx $621 for 52 bags of GreenFider R-19. $400 is nothing to sneer at, but I would have expected a lot more savings if I do the work.

Batts would work but seem to be around $900 for 630 sq ft R11 plus 630 sq ft of R30 to put on top
 
  #3  
Old 10-24-16, 02:07 PM
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The framing changes direction because there is a supporting (load bearing) wall (or beam) beneath those joist ends.

I doubt that the "sagged" insulation was ever even with the top of the joists. As you know, the vapor retarder is also on the wrong side assuming you are in a predominantly heating climate area.

The porch has no insulation over it as it is an unconditioned space. Insulation would be of minimal or no value. That is probably the same excuse for the three-season room although I personally would want it insulated.

The term "attic" insulation is for people that don't know about vapor retarders.

I would opt for having it professionally blown, adding baffles where needed beforehand. Part of that is because I am no longer as agile as I once was and part is because it is a dirty job. When I was in my twenties I blew insulation in the attics of two different houses and I was covered with that stuff. If you do it yourself be SURE to wear full coverage coveralls AND wear a respirator.
 
  #4  
Old 10-24-16, 02:55 PM
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IMO the biggest advantage of blown versus batts is the blown insulation can give complete coverage with no gaps anywhere which is more difficult to do with batts. Batts can be advantageous near the attic opening.
 
  #5  
Old 10-24-16, 05:57 PM
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I've added insulation to several homes, every one was done with blown in cellulose insulation.

Think of this, how in the heck are you going to haul up into the attic all the bundles of insulation batts, then attempt to crawl around on top of the ceiling joists, installing and cutting each batt? Would not wish that on my worst enemy!!

Blown in insulation is a dirty job but the prep work is the same. The installation (with some help) is straight forward and when done it's sealed with no gaps.

I see they now have chopped fiberglass similar to cellulose, might be ok but personally I hate working with any kind of fiberglass,
 
  #6  
Old 10-24-16, 07:02 PM
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For "only" $400 savings I wouldn't think about it for a second. Insulating an attic is an unpleasant task at best.

But I would be very sure that the contractor you use will do all the things you have listed....install baffles, install correct amount to achieve correct R value, etc. This is the time to deal with air sealing as well, and that adds to the cost.

It's pretty easy to chintz on blown in insulation and still make it look like you got the depth you expect, so make sure you get a reputable contractor.

There's not much point in insulating a porch ceiling (assuming it's not enclosed with insulated walls). You want the insulation to extend over the top plate of the exterior wall, but you can stop there. If you use blown in baffles will be required to prevent the insulation from spilling into the porch roof area.
 
  #7  
Old 10-25-16, 03:31 AM
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It's pretty easy to chintz on blown in insulation and still make it look like you got the depth you expect, so make sure you get a reputable contractor.
Back in the 80's in central fla there was a big insulation company that got caught 'fluffing up' the cellulose as it was blown in. They had invented a device that would do that, saved them a lot of material. They eventually got caught and because a significant portion of their work was FHA and VA financed homes it was a federal investigation. I don't remember the fines but they had to go back and re insulate 1,000's of houses.

You always want to check the reputation of anyone you hire to work on your home!
 
  #8  
Old 10-25-16, 04:08 AM
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Thumbs up

The price you are paying for cellulose is going to be higher than the insulation contractor will pay. He is buying thousands of bags yearly. This impacts what you are perceiving as the savings relative to having it done by a contractor.

The batts you currently have are more than likely faced with kraft paper on both sides but only the side facing the interior of the house has a bituminous coating to act as a vapor retarder.

Adding the appropriate baffles to keep air flow from the eaves is important as well as protecting any can lights from the direct contact of insulation.

If it were not a particularly difficult task, I would lift the current batts where wall partition top plates intersect the ceiling and seal any gaps with the small cans of foam. Also check for drop soffits in kitchen and bathrooms and make sure that air flows leading into those areas from adjacent walls cavities is sealed off.

Your attic has a lot of working room so moving around with the hose to blow cellulose would be relatively easy compared to many I have seen.

The true advantage of cellulose is a much more consistent coverage around irregularities such as the framing issues you pointed out.

Careful about adding too much insulation. The colder you make the attic, the greater the chance that moist air and vapor flowing from the home will condense on the back of the roof deck. R-49 may sound appealing from an energy saving standpoint but if you have a high relative humidity in the home you must be cautious about how the added insulation will impact adjacent materials from a moisture standpoint.

If you use a contractor, he may very well be using bags that contain more material than what you buy in a retail setting.so ask him to show you the prescribed number of bags called for and provide a statement indicating that he has installed the correct number of bags for the area included.
 
  #9  
Old 10-25-16, 06:39 AM
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wow! Great comments as always!

So, the contractor (I used him on my last house, he has a solid rep locally) will be adding 12" of insulation on top of the 2" I currently have. He also said that my soffit vents arent necessary because I dont have a ridge vent... Thus he is NOT planning on installing baffles at the soffit vents (he says he can keep them clear by keeping less material in those areas, but he doesnt think its necessary). This is the only thing that bugs me about his approach

For the record, I clearly have soffit vents, I have a vent on the wall on both sides of the house (one in each attic) and there are openings to allow air from the lower attic to get to the upper attic. I also have a power vent up there (a fan that turns on a a specific temp to exhaust the air)

In terms of the existing insulation, it is faced on only one side (and the paper is quite brittle, I might add

Assuming I do hire him, he gave me a proposal to do the following
  1. Add 12" of cellulose to existing insulation in lower attic to achieve around R-49. Also will add buble wrap and insulation a knee wall between the two halves of the house. He will use metal to keep insulation away from can lights and will insulate the 3 season room as well -- approx $1k
  2. 2nd area would be the upper attic. He will fashion some kind of barrier to keep center walkway and floor I put down accessible and blow 8" of cellulose on top of the 6" of fiberglass thats in place -- $450
  3. 3rd area: there is a garage under two of the bedrooms, and he says those are notorious for temp issues. He would punch holes in garage ceiling and blow in insulation and do one coat of patch to seal it up: another $1k

So, I am also trying to decide if I should only have him do the lower attic (my original project, which needs the most insulation, but its over the living room, dining room, kitchen) or that plus upper attic (over the three bedrooms and bathroom) or do all three for $2500 (funny how the project grows, no?)
 
  #10  
Old 10-25-16, 06:45 AM
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I'm a little concerned about #3. There should be insulation already in the floor although it may not be enough. I'd want to know how much dead space there is in order to know how feasible it is to blow more in. Might want to cut a test hole to find out. IMO if there isn't much room or obstructions it wouldn't make any sense. How do those rooms feel [temp wise] in the winter?
 
  #11  
Old 10-25-16, 07:55 AM
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we just bought this house over the summer. Maybe we should hold off on this until I know for sure. I will say this: the 'upper' part of the house (the three bedrooms and bathroom) was a good 5-10 degrees warmer this summer.

I also have noticed a bit of a chill in those bedrooms as the temp is starting to drop. Weighing the value prop of doing it all now versus a $1k job becoming $1400 later (no idea how much more it would be later, just a hypothetical number).

I DO have a hole in the ceiling punched by electricians-- I should poke my camera in there (just remembered this)
 
  #12  
Old 10-25-16, 10:45 AM
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Does what he said about the soffit vents (blocking them is OK as I have a powered fan vent vs ridge vent) make sense?
 
  #13  
Old 10-25-16, 05:11 PM
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The colder you make the attic, the greater the chance that moist air and vapor flowing from the home will condense on the back of the roof deck. R-49 may sound appealing from an energy saving standpoint but if you have a high relative humidity in the home you must be cautious about how the added insulation will impact adjacent materials from a moisture standpoint.

If you have moist air in the attic you have other issue like bathroom vents that exit in the attic, a really bad situation.

You can put as much insulation as you want but you MUST have sufficient ventilation, thus the concern of blocked soffit vents and roof/ridge vents!

With proper insulation and venting a power vent really is not needed.

In theory if no heat ever entered the attic from the house you would have a perfect situation!
 
  #14  
Old 10-25-16, 07:38 PM
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" You can put as much insulation as you want but you MUST have sufficient ventilation, thus the concern of blocked soffit vents and roof/ridge vents! "

Can you define sufficient ventilation?? Given the wide and sometimes quickly fluctuating range of variables that can be significant determinants of attic moisture issues, "sufficient" at one point in time can be very different than a subsequent point in time.

Also, keeping in mind that the house is "50's/60's" era construction, the basement can be a significant contributor to background moisture levels as it is doubtful that vapor/moisture retarders were utilized below the floor and on the exterior of the foundation or below the footings.
 
  #15  
Old 10-26-16, 06:53 AM
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Ok... Couple of items raised in previous points:

Vents:
  • I have two attics. They are connected (the ridge of the lower attic is approximately half way up the upper attic.
  • The attics have openings to allow air to flow between
  • There is a (gable?) vent in each attic on the exterior wall
  • In the upper attic, there is a fully functioning power fan-vent
  • Bathroom fan (newly installed) is vented outside, away from any opening back in to the attic (per code--3' minimum distance)
  • There are soffit vents, but they look like some may be blocked already--I am concerned about whether we can block them (installer says yes) or if this insulation installer can actually just 'use less material' near the soffit vents and that will keep them sufficiently open

I should mention that I have noticed some of the rafters (when I said rafters in previous posts, I was actually referring to ceiling joists!) in the LOWER attic are bowing a bit. In the upper attic, I noticed a small area of dry rot (one rafter only... a little splintering)


The basement:
We have a basement under the lower side of the house. The upper side of the house is on a slab. In the one basement, there is no vapor barrier of any kind (we redid the floors and ran some wire), at least on the floor plane. I do know I need to insulate my HVAC ducts (next project!).
 
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