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Rad777
01-29-2009, 06:31 PM
Home is built in 1888 in NE Wisconsin. Gutted out the living room due to 2nd story bathroom leak prior to buying it. The room is around 24x35 with a 9ft ceiling. Once the wire/plaster combo was removed, I lost 1.5" of wall thickness which will have to be furred out to meet finished flooring. The siding has 1.5" foam board behind it. My questions are these:

1. Can I get away with R19? All the framing is 2x4... If I fur out the studs 2 inches could I use R19(6")? instead of R13(3.5")

2. If I do fur out and use R19, could I simply run the electrical between the strips of furring (in front of insulation)?

Thank You

hj
01-30-2009, 06:27 AM
1. Why wouldn't you use the thicker insulation?
2. As long as you use nail protective plates over the wiring there is no problem. It would probably violate the electrician's first rule, "NEVER put a wire where it will be out of the way". Electricians ALWAYS put their wires where they cause the most problems for all the other trades.

GabeS
01-30-2009, 08:00 AM
It's okay to compress the insulation a bit. If you look up compressed insulation charts you would see R-values for fiberglass batt insulation depending on how compressed they were.

Compressed r-19 in a 2x4 wall has higher r-value than r-13 in a 2x4 wall. Don't forget vapor barrier.

RRW
01-30-2009, 09:16 AM
Furring out the walls will certainly allow you to increase the insulation but the problem can also be solved by just running a matching board around the base to take up the space. It would look just fine.

Nate R
01-31-2009, 07:36 AM
24X35? My house could fit inside that room! :eek:

Scuba_Dave
01-31-2009, 09:05 AM
It's okay to compress the insulation a bit. If you look up compressed insulation charts you would see R-values for fiberglass batt insulation depending on how compressed they were.

Compressed r-19 in a 2x4 wall has higher r-value than r-13 in a 2x4 wall. Don't forget vapor barrier.

Actually according to a chart I saved R-19 in a 2x4 wall is R13

I would furr out the walls & go with more insulation
Or you could go with R15 in a 2x4 wall
Heating & cooling costs long term do not go down

http://i4.photobucket.com/albums/y105/Daveywb/Construction/Compression.jpg

cc777z
01-31-2009, 02:41 PM
Have you considered blown in foam insulation? It is blown in wet with a special sprayer and drys hard. It also seals every little crack and does not need a vapor barrior. It has a R7 per inch thickness. So a 4 inch depth would be an R28. You don't have to put that much in if you don't want to. 2 inches would be an R14.

It is more expensive than fiberglass bats. But by sealing all the little air leaks the benefit is even greater than the R rating. It also strengthens the walls.

It's considered 99% water resistant and approved for sealing the inside basement walls against moisture.

For more information you can do a google search on spray foam insulation.

There should be several contractors in our area who provide this service.

Also do you know what type 1 1/2 foam insulation is already in place? If it is the Pink styrofoam you could already have as much as an R5 to R7 in place.

Rad777
01-31-2009, 04:00 PM
Compressed r-19 in a 2x4 wall has higher r-value than r-13 in a 2x4 wall. Don't forget vapor barrier.

Would faced suffice?

Thank you ScubaDave for the chart... Question however, if anyone knows... Why is R19 thicker than R21? I think I will furr out an an inch and go with R21.

Also included a photo of one corner, just because


If it is the Pink styrofoam you could already have as much as an R5 to R7 in place.
Yep just double checked, it is that pink stuff about ~1.4" thick

Thanks

Scuba_Dave
01-31-2009, 07:08 PM
I'm not sure on the thickness question
I just had to go check a roll of R19 - yup 6.25"
That ticks me off a little that its only R18 compressed into a 2x6 wall
But R19 is at the big box store & R21 isn't
And the place nearby that carries R21 charges a LOT more

I do know the R30c & R38C are for Cathedral ceilings - more dense

frenchie
02-01-2009, 11:10 AM
The R-21 is probably high-density fiberglass (basically, pre-compressed), that's why it's thinner & more expensive.

GabeS
02-01-2009, 04:15 PM
Make sure you inpect all of you studs and joists while you have the walls open. Take a flat head screwdriver and poke all wood every foot of so on the sides and face. Check for termite damage. Look for rot and mold. Sister up where needed. I noticed some of the studs were already repaired.

What size are you ceiling joists, span, spacing? What's above?

Rad777
02-05-2009, 06:50 PM
What size are you ceiling joists, span, spacing? What's above?

I will measure and take a photo tomorrow and post it. Thanks for the replies everyone!