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msmity29
05-15-2006, 12:11 PM
We are having a new home built and I am trying to figure out ways to make it more energy efficient. The builder is in the middle of the framing stage and I am trying to prepare for when he are finished.

First, I should probably provide some background on the house itself. It is being built in the suburbs of Chicago. It is a 2-story with an unfinished basement. The square footage is approximately 2,600 ft. We upgraded to 2x6 exterior walls with R19 insulation. The ceiling will be insulated with total R-38 (batts with blown insulation over top). The wall construction goes from exterior to interior like this: vinyl siding (about third of front house will be stone), Menard's brand upgraded Tyvak, 7/16" OSB, 2x6 walls with R-19 with poly-vapor barrier, drywall. There was no foam placed around foundation (was told builder didn't do that). We upgraded to a Carrier 91% effieciency furnace and a dual zone Honeywell system. The air conditioner is a Carrier 10SEER (may be upgraded to 13SEER at no cost if builder runs out of 10SEER). The windows are from Crestline with low-e glass and Argon filled.

We already know we want to insulate the two exterior walls in the garage that aren't. And we would like to insulate a couple of interior walls between rooms such as Master Bedroon/Laundry Room etc for sound damping. In both cases we will probably just use R13 batt insulation, but any other recommendations/advice would be greatly appreciated. We are on a pretty tight budget so we need to keep the prices on these two projects relatively low.

I would also appreciate any advice on sealing critical places on the house. For example, a thin (maybe 1/8") foam gasket was placed between the sill plate and foundation. However, it looks like there are gaps between some of the lengths of foam. Should I seal these gaps with caulk etc? If so, should I do it from the exterior or interior? Also, should I caulk between gaps in the OSB? What should I look for on the tyvek to make sure it is sealed correctly? Any and all helped will be greatly appreciated as this is our first house and we are pretty naive in most building processes. Thanks in advance!

rabadger
05-16-2006, 07:33 AM
Try this thread, it may answer your question.

http://www.construction-resource.com/forum/showthread.php?t=4805

David
05-16-2006, 09:11 AM
We upgraded to 2x6 exterior walls with R19 insulation.
Minimum!

The ceiling will be insulated with total R-38 (batts with blown insulation over top).
Good.

There was no foam placed around foundation (was told builder didn't do that).
Now you are told builder is lazy, IMO.

We upgraded to a Carrier 91% effieciency furnace and a dual zone Honeywell system. The air conditioner is a Carrier 10SEER (may be upgraded to 13SEER at no cost if builder runs out of 10SEER).
10SEER = no good.

The windows are from Crestline with low-e glass and Argon filled.
Windows are your weak spots. Take 1/U = R. Windows are rated with U. Walls with R. So this is the relationship. You'll see windows are your big loser of heat.

Take photos of your window flashing as soon as it goes in. Post them here.

We already know we want to insulate the two exterior walls in the garage that aren't. And we would like to insulate a couple of interior walls between rooms such as Master Bedroon/Laundry Room etc for sound damping.
Search for a thread on sound proofing. Basically, your sound damping will do an okay job, but don't expect it to do much. You'll need to insulate in the joists below and above the MB/L wall, too. IMO, I'd insulate above and below and all around the MBR with batts.


In both cases we will probably just use R13 batt insulation, but any other recommendations/advice would be greatly appreciated.

Your garage door. See if you can get an insulated one.


We are on a pretty tight budget so we need to keep the prices on these two projects relatively low. Sound proofing can get expensive. Use batts and cut foam if you have some.

I would also appreciate any advice on sealing critical places on the house. For example, a thin (maybe 1/8") foam gasket was placed between the sill plate and foundation. However, it looks like there are gaps between some of the lengths of foam. Should I seal these gaps with caulk etc? If so, should I do it from the exterior or interior?
Yes, caulk both sides. Did you tell the builder about the gaps? Does he not care?

Also, should I caulk between gaps in the OSB? I assume there are studs behind these gaps, right!!?? Are there studs behind these gaps??

You should caulk any holes that penetrate into the attic (before insulation!). Use expanding foam.

What should I look for on the tyvek to make sure it is sealed correctly? IMO, housewrap should not be sealed horizontally. Any water that gets in needs a path out. Horizontal seams should overlap by 6" to 8" I believe.

msmity29
05-17-2006, 07:08 AM
Thanks for the info! The windows we are having installed are pretty good. They have a U value below .35. Do you think it would be worthwhile to dig up around the foundation and run 4x8 sheets of foam horizontally along it? I know it would only go down 4 feet then but it might be better than nothing. What are your thoughts?

rabadger
05-17-2006, 07:24 AM
Once again.....

In the 2003 residential code book Kane and DuPage counties are in zone 14. From table N1102.1

Wall R-21
Ceiling R-49
Floors R-21
Basement walls R-11
Slab perimeter R value and depth R-11, 4ft
Crawl space walls R-20
Maximum glazing U-Factor .035

It also states in N1102.1.1 Exterior walls.
The min. required R-value in table N1102.1 shall be met by the sum of the R-values of the insulation materials installed in the framing cavities and/or insulating sheathing applied, and not by framing, drywall, structural sheathing, or exterior siding materials. Insulation separated from the conditioned space by a vented space shall not be counted towards the required R-value.

Find out what codes the town and county follow so you don't cause a fuss if not needed

David
05-17-2006, 08:47 AM
Richard - Can one meet code by applying the rigid insulation to the interrior of the basement walls?

rabadger
05-17-2006, 09:06 AM
An R-11 wall is a R-11 wall. Put in on the inside or outside. But remember on the outside it stops at the finished grade level or below.

David
05-17-2006, 09:15 AM
I thought so. The reason I say it is because she may have to do it on her own. If so, insulating the interrior would be easier, IMO.

Also, she needs to insulate (best with 2" rigid foam) the basement joists along the exterior perimeter.

msmity29
05-19-2006, 09:19 AM
I checked with the city and the building code specified the following:

Maximum Glazing U-Factor: .35
Ceiling: R-38
Walls: R-13
Floors: R-11
Basement Walls: R-0
Slab Perimeter R value and depth: R-5, 2 ft
Crawl Space Walls R-11

rabadger
05-19-2006, 09:30 AM
There you have it. All you need to do now is meet what they say for the inspection or go better. In our area I would go with the better numbers. Remember one thing. Make sure the HVAC know so they can adjust the load calculations.

David
05-19-2006, 11:10 AM
Richard, is it possible they don't run load calcs for each home. Perhaps they run them once for each model, and just make assumptions. I know they shouldn't, but I have a feeling production builders are cutting these corners.

rabadger
05-29-2006, 06:44 AM
Production builders don't do load calculations. The HVAC guys should but most don't. They just guess at it. Some get pretty close with the guess work. Most owners end up with two oversized systems in the home.

If it were me I would be insulating to the standards I posted. From what the original poster stated the town has never upgraded the insulations standards from 20 years ago. If that's the case he could end up with oversized equipment, and humidity problems.