# alabama best practice



## Windows on Wash (Aug 30, 2011)

If anything, it would go towards the warm wall (often the exterior as you move South).

What is the exterior sheathing/cladding?


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## tool man Taylor (Mar 19, 2013)

The exterior is stone masonry... House built in '74... We live in the northern part of alabama. Ive seen the maps from building science and thats where its unclear to me what would be best.


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## Windows on Wash (Aug 30, 2011)

In this case, I don't want to see a vapor barrier at all.

What is the exterior construction like? You have the stone but does it have sheathing?


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## tool man Taylor (Mar 19, 2013)

I'm not exactly sure what it is but when i pull insulation back I see a black wall... So I'm guessing some kind of backer board? It currently has r11 insulation with paper on the front and back of the batt... Never seen this before... Insulation looks fine but since I have the walls opened up due to renovations we are updating insulation.


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## BigJim (Sep 2, 2008)

I am just a hair north of you in Chattanooga, we use the faced batts with the face toward the inside of the house. If you are seeing black chances are it is black board.


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## Gary in WA (Mar 11, 2009)

Go ahead and use the faced batt, you'll be fine; Fig.6;http://www.google.com/url?sa=t&rct=...sg=AFQjCNHnJQGqBm_YLikw097AhZCgy4ETIg&cad=rja

Cavity may only dry to the inside (if no air gap at stone/Celotex-- variable perms; fairly open), just no poly. http://www.inspectapedia.com/structure/Fiberboard_Sheathing.htm

The newer R-13 is a Medium density rather than the Low density (R-11), replace it for no inherent convective loops degrading the R-value; pp.45-48; http://www.buildingscienceconsultin...010-03-10_When_R-Value_Doesn t_Measure_Up.pdf

ADA the drywall; http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach/

Low-exp. canned foam around the windows; http://books.google.com/books?id=a2...CBMQ6AEwAA#v=onepage&q=Proskiw (1995)&f=false

Face staple rather than side staple, FG batt (thermal barrier) requires FULL contact with drywall (air barrier), no convective loops; pp. 48

Optimum -- prevent thermal bridging of the studs- pp.39. Use 1/2" foil-faced polyiso strips on the studs inside edges, longer drywall screws. Caulk all joints of wood framing/Celotex (top/bottom/sides), and joint of bottom plate/sub-floor to air seal wall from 1/16" air gaps of exterior temp air.

Gary


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## tool man Taylor (Mar 19, 2013)

Thank you all. 

Next question... Ceiling insulation will be replaced... Thinking about doing cellulose without any vapor retarder... Any problems with that ? Will air sealing and paint and primer be sufficient?


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## BigJim (Sep 2, 2008)

Things have changed so much since I was contracting I can't keep up now, I really liked the cellulose a lot, one thing to check is if your house is old, the sheet rock sometimes was nailed with common nails, not like the nails and screws of today, the old nails could pull loose with the weight of the moist cellulose when it is installed.


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## tool man Taylor (Mar 19, 2013)

Thanks... We are replacing all the paneling and ceiling in all rooms... One at a time since we have to live in it.

When we drop the ceilings the current batts that are in the attic fall out and not in good enough condition to put back so we are going to replace attic insulation room by room over time.

Joist are 2x6 and I was going to install faced r19 but all I find around here is r19 unfaced..... 

So my options are to install higher r value unfaced batts or install r13 faced batts and add to it later. After I think about it cellulose prob wouldn't be good to do until I get all the rooms done.


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## Gary in WA (Mar 11, 2009)

May require venting in each cathedral bay... the unfaced is for attics- hence 6-1/4" thick- lose R-1 if installing in a wall at 5-1/2" instantly. R-19 (0.44 #ft3) is a very low density insulation= the lowest/poorest they make, I'd re-think a little. How hard would it be to furr down the rafters, and keep an air space next to the roof sheathing= 1-1/2".

Gary


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## tool man Taylor (Mar 19, 2013)

Thank you.
Here is what I'm working with. This is the hallway currently being redone....
As you can see the insulation has been removed from the ceiling in that room.

Since I'm only replacing insulation in the attic above the hallway. Other parts of the attic will be done once I get to those rooms. But for now I need to replace the batts directly above the hallway ceiling so I can drywall the ceiling. Like I've mentioned I'll be redoing other room in a similar manner so loose fill prob won't work until I get all the rooms and ceilings done.

Depending on if I need faced insulation or not these are my options...

1. Faced r13 (then add unfaced later on)
2. Unfaced r19 (then add unfaced later on)
3. Unfaced r30.


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## tool man Taylor (Mar 19, 2013)

Also I'm not opposed to loose fill if you think its doable to do the ceiling one room at a time. It'll take maybe 5 bags to do the hallway... But I think I need 10 bags to use Lowes machine which would be fine since I'll need more bags later on in other parts of the house. 

That's only if using loose fill cellulose without a vapor retarder besides air sealing and paint and primer would be fine.


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## Gary in WA (Mar 11, 2009)

No vapor retarder required in your vented attic, cathedral ceiling- yes. I would batt it, at least around the low-slope to get the R-value there, or rigid XPS: http://www.diychatroom.com/f103/my-attic-insulation-adequate-196546/index2/
Keep in mind the R-13 is a medium density (good) and the R-19 and R-30 both a low-density (poor) at slowing air/heat movement. 

IMO, the faced batts on exterior wall will have convective loops (bad) with side stapling rather than face stapling; 3a, 3b; https://docs.google.com/viewer?a=v&...9EVKki&sig=AHIEtbTb5UnlVQ7Je0R-_NGatSVo3wzmAQ

Gary


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