attached garage

warmwxrules · 11-18-11, 12:14 PM

If I plan to wrap my house (single story ranch/uninsulated as it sits now) with 2 or 4 inches of polyiso (along with filling the cavity with cellulose) do I also have to do the same with a 24x24 attached garage? If I don't, then what about the thicker walls I now will have on the house?

I'm still working through all of this. I need to price things out (I'll have to buy siding also/mine is garbage). The house portion is about 1000sq ft. Also have a full, uninsulated basement that needs to be addressed.

Moving to S. Florida for the winter is not an option...yet.

herlichka · 11-18-11, 06:18 PM

It's up to you whether the garage gets insulated, or not; it depends if you want to heat the garage full time, occasionally, or not at all. If you choose to not insulate, it will be important to insulate the common wall between the house and the garage. Pay particular attention to the gas barrier between the house, including the attic space, and the garage.
If you do insulate the garage, you should not install a poly vapor barrier on the inside of any of the garage walls. The common wall between the house and garage would wind up with a vapor barrier on both sides of the wall, trapping any moisture in the insulation. The other walls should not have a vapor barrier, even if the garage is heated, because the wide temperature changes (heat on, heat off,, door open, door closed) will cause condensation on the insulation. This is one of the few situations where the wall must breathe.
If you are trying to keep the siding lined up along the walls where the house and garage meet, you may have to fur out your walls to match. If you factor these costs against the cost of insulation, you may find the insulation may not be a lot more money and/or effort. And, when you do make that move to South Florida, the extra resale value may help!

DEnd · 11-18-11, 06:19 PM

You only "have" to do the sides that are flush with an outside wall of the house. You can also add spacers between the sheathing and the siding. Either way you must also increase the insulation and replace the firewall protection on the shared walls/ceiling. Typical firewall protection in a residential house is two layers of drywall on the garage side with overlapped joints, with the sheets put up horizontally. To the best of my knowledge however this does not create a rated firewall. Don't forget you also need the firewall in the garage attic, or possibly on every wall. This is also a good time to think about any upgrades you want to do to your garage. My suggestions are to increase your lighting and electrical outlets and circuits, and run at least one 3 phase outlet. If you have an air compressor consider adding air lines to the walls. Consider your storage needs and plan on adding cabinets as well as counter space. I'd also consider adding insulation to the other walls of the garage as well, though you'd still have to increase the insulation on the shared wall, and think about adding some sort of heater to the space (only on when actively using the space of course). This could allow you to use your garage as a work space for projects in the winter. If you want some garage porn visit the forums at The Garage Journal While they have some high dollar drool worthy garages there are a lot of very cost effective and low budget ideas there as well.

warmwxrules · 11-18-11, 08:18 PM

Ok... I don't look to heat the garage, but wouldn't mind it being "warmer" in winter...

The garage is "new" (house is from the 50's, garage was added around 2000)...its not unfinished, its just not insulated (for what I can tell), even the garage door isn't (that is leaking air badly/16x7). The wall between the house and garage was also redone on the garage side (drywall/insulation)...I know this because I had to run a cable though it and I noticed it was insulated (fiberglass).

The siding on the house is from the early 90's, but is badly faded. Man i hate vinyl siding. Plus the color is outdated. So i figure the perfect time to insulate this beast is when I open her up.

I'll have to price this stuff out (I love Menards), and see where I'm at. Right now I'm just trying to figure out a list of materials.

DEnd · 11-18-11, 09:20 PM

Look into something like hardiboard siding. It is a low maintenance cement board type siding that holds paint very well. IIRC painting is supposed to last like 25-50 years with it. You'll have to look into the details of installing it, and I'd recommend doing something like a rain screen type installation, which involves adding furring strips and spacing the siding away from the wall a bit to allow some airflow on the outside of the sheathing to allow it to dry.

As for warming up your garage you might look into adding some passive solar features to it. You'll have to find someone who has more experience with passive solar than I do. Also since a Garage is a perfered entry point for theives (a good one can open a typical garage door in about 30 seconds) you will probably want to add some window bars or something to at least deter the idiot theives.

Also you will still want to upgrade the insulation on the shared wall, as the garage is typically close to the same temps as the outside. It wouldn't be that great to have a well insulated house only to have it's performance hampered by massive air leaks and inferior insulation in the shared wall.

herlichka · 11-19-11, 08:24 AM

When you replace your siding don't overlook the opportunity to tighten up the building envelope; it's a great time to install "Typar", or "Tyvek", c/w "tuck tape" on all the joints. You will have to build out your window casings, so, again, its a good time to detail the seal around the windows, spray foam, drip flashings, etc. It's a rare chance to seal the sill plate from the outside; maybe a combination of spray foam and caulk. Any protrusions such as receptacles and lights, faucets, gas service, electrical equipment all can be detailed. Another opportunity for improvement may be the soffit finishes, a good time to upgrade the attic ventilation.
I agree with you about vinyl siding, "No vinyl; that's final!" Vinyl fades, the colours become dated very quickly, and, to me it looks like a low budget subdivision finish. The cement board sidings that are now available have a very nice "feel" to them. They are dimensionally stable, deaden sound, and are easily refinished when you want to change colour. But they require some skill to install. You would want to study up, and be sure you have the skillset, tools, and like-minded labour (it's heavy) to install successfully.

Xringer · 11-19-11, 08:38 AM

When I had my 24x24 garage built, I decided it would not be attached, because:

1. Fire code requirements would add extra cost.

2. Sheetrock (per fire code) would mean insulation should be installed, at extra cost.

3. I guessed more modern insulation would have higher R-factors. (Insulate later).

4. Insulation means garage temperatures will often be higher than outdoor temps.

Many people living in this area, believe that driving a car on city streets during
the winter snows, coats the undercarriage with corrosive chemicals.
Their theory is, that corrosive chemical damage to the car,
will be less, when the car is kept at a low temperature.
By cycling the car's temperature above and below 32F, you promote
chemical-Ice mix to melt, corroding your car and damaging your garage floor.

5. Having seen car fires, I decided that I would sleep better, without
worrying about a car fire in the garage.

http://media.masslive.com/republican...9-standard.jpg
http://media.pennlive.com/midstate_i...ac0a0d90b5.jpg
http://www.annarbor.com/assets/thumb...firephoto1.jpg
http://www.myssnews.com/images/stori...GarageFire.jpg

6. More bad news? Google "car left running in garage"..

S-F · 11-19-11, 10:49 AM

You and I are in very similar situations. I have taken care of the basement in my 50's 1100 Sq. Ft. ranch as it is and in the spring will be taking the outsulate approach for the above grade portions. I have one word of advice for you, and anyone else for that matter, which is to never try to remove a portion of your house from the thermal boundary. Honestly it can't be done properly. Just outsulate the garage also. It will be easier and more effective. The fact that the geometry of the house has been made more complicated sucks. The beauty of a ranch, and the reason I chose one, is because it's such a simple shape to work with. Once you start to add things like additions, and hips and valleys in the roof you make it much more difficult to properly insulate a house. But all hope is not lost! Just make sure to meticulously detail the transitions between the new and old work. You said 2" or 4". DOn't screw around. If you're going to do it you should do it right the first time and go for 4". And a rain screen is a must for this kind of thing. Not only will your siding and pain job last longer (some studies I have seen suggest that a paint job will last as long as 15 - 20 years) you will also give some capacity to the wall to dry to the exterior, which you are throwing away almost completely with a vapor impermeable sheathing.

Best of luck!

warmwxrules · 11-19-11, 11:26 AM

SF-

I agree. Its looking likely that I'll just do everything. My roof is a hip roof (not sure if that is typical for a ranch), but the house is basically a rectangle (the front juts out a few feet on one end in the front). I have 24" overhangs all the way around the house.

That garage door I have looks like a huge leak source. I'm going to try to adjust today and see if i can fix some of the gaps. Part of me wants to replace with with a new insulated door, but the door is in very good shape. I once was offered an insulated door for nothing...ooops!

S-F · 11-19-11, 12:03 PM

Simply get a qlon kit for the door and one of those door sweeps which is activated by a little screw to press down on the floor. If it doesn't have a window and you don't care if it's shiny you could cut a piece of polyiso to fit the door, glue it on the garage side with 1 part foam and some screws/strapping and tape up the edges of exposed foam with foil tape. Even though my basement door is insulated I'll be doing this once I get a free minute. But once the garage in insulated this might not matter?

Your walls are going to be about R 40. Once you start approaching R 30 everything that isn't wall quickly dominates the heat loss. Every Sq. Ft. of things not R 40 wall you can replace with R 40 wall, or something similar, the better you'll be.

11-18-11, 12:14 PM	#1
warmwxrules Helper EcoRenovator Join Date: Nov 2011 Location: La Crosse, WI Posts: 78 Thanks: 0 Thanked 3 Times in 3 Posts	attached garage If I plan to wrap my house (single story ranch/uninsulated as it sits now) with 2 or 4 inches of polyiso (along with filling the cavity with cellulose) do I also have to do the same with a 24x24 attached garage? If I don't, then what about the thicker walls I now will have on the house? I'm still working through all of this. I need to price things out (I'll have to buy siding also/mine is garbage). The house portion is about 1000sq ft. Also have a full, uninsulated basement that needs to be addressed. Moving to S. Florida for the winter is not an option...yet.

11-18-11, 09:20 PM	#5
DEnd Apprentice EcoRenovator Join Date: Nov 2011 Location: NC Posts: 117 Thanks: 6 Thanked 27 Times in 25 Posts	Look into something like hardiboard siding. It is a low maintenance cement board type siding that holds paint very well. IIRC painting is supposed to last like 25-50 years with it. You'll have to look into the details of installing it, and I'd recommend doing something like a rain screen type installation, which involves adding furring strips and spacing the siding away from the wall a bit to allow some airflow on the outside of the sheathing to allow it to dry. As for warming up your garage you might look into adding some passive solar features to it. You'll have to find someone who has more experience with passive solar than I do. Also since a Garage is a perfered entry point for theives (a good one can open a typical garage door in about 30 seconds) you will probably want to add some window bars or something to at least deter the idiot theives. Also you will still want to upgrade the insulation on the shared wall, as the garage is typically close to the same temps as the outside. It wouldn't be that great to have a well insulated house only to have it's performance hampered by massive air leaks and inferior insulation in the shared wall. Last edited by DEnd; 11-18-11 at 09:25 PM..

11-19-11, 08:38 AM	#7
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Car rust prevention? When I had my 24x24 garage built, I decided it would not be attached, because: 1. Fire code requirements would add extra cost. 2. Sheetrock (per fire code) would mean insulation should be installed, at extra cost. 3. I guessed more modern insulation would have higher R-factors. (Insulate later). 4. Insulation means garage temperatures will often be higher than outdoor temps. Many people living in this area, believe that driving a car on city streets during the winter snows, coats the undercarriage with corrosive chemicals. Their theory is, that corrosive chemical damage to the car, will be less, when the car is kept at a low temperature. By cycling the car's temperature above and below 32F, you promote chemical-Ice mix to melt, corroding your car and damaging your garage floor. 5. Having seen car fires, I decided that I would sleep better, without worrying about a car fire in the garage. http://media.masslive.com/republican...9-standard.jpg http://media.pennlive.com/midstate_i...ac0a0d90b5.jpg http://www.annarbor.com/assets/thumb...firephoto1.jpg http://www.myssnews.com/images/stori...GarageFire.jpg 6. More bad news? Google "car left running in garage".. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

11-19-11, 12:03 PM	#10
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	Simply get a qlon kit for the door and one of those door sweeps which is activated by a little screw to press down on the floor. If it doesn't have a window and you don't care if it's shiny you could cut a piece of polyiso to fit the door, glue it on the garage side with 1 part foam and some screws/strapping and tape up the edges of exposed foam with foil tape. Even though my basement door is insulated I'll be doing this once I get a free minute. But once the garage in insulated this might not matter? Your walls are going to be about R 40. Once you start approaching R 30 everything that isn't wall quickly dominates the heat loss. Every Sq. Ft. of things not R 40 wall you can replace with R 40 wall, or something similar, the better you'll be. Last edited by S-F; 11-19-11 at 12:06 PM..

11-18-11, 06:18 PM	#2
herlichka Apprentice EcoRenovator Join Date: Oct 2010 Location: Simcoe County, Ontario, Canada Posts: 102 Thanks: 11 Thanked 15 Times in 10 Posts	It's up to you whether the garage gets insulated, or not; it depends if you want to heat the garage full time, occasionally, or not at all. If you choose to not insulate, it will be important to insulate the common wall between the house and the garage. Pay particular attention to the gas barrier between the house, including the attic space, and the garage. If you do insulate the garage, you should not install a poly vapor barrier on the inside of any of the garage walls. The common wall between the house and garage would wind up with a vapor barrier on both sides of the wall, trapping any moisture in the insulation. The other walls should not have a vapor barrier, even if the garage is heated, because the wide temperature changes (heat on, heat off,, door open, door closed) will cause condensation on the insulation. This is one of the few situations where the wall must breathe. If you are trying to keep the siding lined up along the walls where the house and garage meet, you may have to fur out your walls to match. If you factor these costs against the cost of insulation, you may find the insulation may not be a lot more money and/or effort. And, when you do make that move to South Florida, the extra resale value may help!

11-18-11, 06:19 PM	#3
DEnd Apprentice EcoRenovator Join Date: Nov 2011 Location: NC Posts: 117 Thanks: 6 Thanked 27 Times in 25 Posts	You only "have" to do the sides that are flush with an outside wall of the house. You can also add spacers between the sheathing and the siding. Either way you must also increase the insulation and replace the firewall protection on the shared walls/ceiling. Typical firewall protection in a residential house is two layers of drywall on the garage side with overlapped joints, with the sheets put up horizontally. To the best of my knowledge however this does not create a rated firewall. Don't forget you also need the firewall in the garage attic, or possibly on every wall. This is also a good time to think about any upgrades you want to do to your garage. My suggestions are to increase your lighting and electrical outlets and circuits, and run at least one 3 phase outlet. If you have an air compressor consider adding air lines to the walls. Consider your storage needs and plan on adding cabinets as well as counter space. I'd also consider adding insulation to the other walls of the garage as well, though you'd still have to increase the insulation on the shared wall, and think about adding some sort of heater to the space (only on when actively using the space of course). This could allow you to use your garage as a work space for projects in the winter. If you want some garage porn visit the forums at The Garage Journal While they have some high dollar drool worthy garages there are a lot of very cost effective and low budget ideas there as well.

11-18-11, 08:18 PM	#4
warmwxrules Helper EcoRenovator Join Date: Nov 2011 Location: La Crosse, WI Posts: 78 Thanks: 0 Thanked 3 Times in 3 Posts	Ok... I don't look to heat the garage, but wouldn't mind it being "warmer" in winter... The garage is "new" (house is from the 50's, garage was added around 2000)...its not unfinished, its just not insulated (for what I can tell), even the garage door isn't (that is leaking air badly/16x7). The wall between the house and garage was also redone on the garage side (drywall/insulation)...I know this because I had to run a cable though it and I noticed it was insulated (fiberglass). The siding on the house is from the early 90's, but is badly faded. Man i hate vinyl siding. Plus the color is outdated. So i figure the perfect time to insulate this beast is when I open her up. I'll have to price this stuff out (I love Menards), and see where I'm at. Right now I'm just trying to figure out a list of materials.

11-19-11, 08:24 AM	#6
herlichka Apprentice EcoRenovator Join Date: Oct 2010 Location: Simcoe County, Ontario, Canada Posts: 102 Thanks: 11 Thanked 15 Times in 10 Posts	When you replace your siding don't overlook the opportunity to tighten up the building envelope; it's a great time to install "Typar", or "Tyvek", c/w "tuck tape" on all the joints. You will have to build out your window casings, so, again, its a good time to detail the seal around the windows, spray foam, drip flashings, etc. It's a rare chance to seal the sill plate from the outside; maybe a combination of spray foam and caulk. Any protrusions such as receptacles and lights, faucets, gas service, electrical equipment all can be detailed. Another opportunity for improvement may be the soffit finishes, a good time to upgrade the attic ventilation. I agree with you about vinyl siding, "No vinyl; that's final!" Vinyl fades, the colours become dated very quickly, and, to me it looks like a low budget subdivision finish. The cement board sidings that are now available have a very nice "feel" to them. They are dimensionally stable, deaden sound, and are easily refinished when you want to change colour. But they require some skill to install. You would want to study up, and be sure you have the skillset, tools, and like-minded labour (it's heavy) to install successfully.

11-19-11, 10:49 AM	#8
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	You and I are in very similar situations. I have taken care of the basement in my 50's 1100 Sq. Ft. ranch as it is and in the spring will be taking the outsulate approach for the above grade portions. I have one word of advice for you, and anyone else for that matter, which is to never try to remove a portion of your house from the thermal boundary. Honestly it can't be done properly. Just outsulate the garage also. It will be easier and more effective. The fact that the geometry of the house has been made more complicated sucks. The beauty of a ranch, and the reason I chose one, is because it's such a simple shape to work with. Once you start to add things like additions, and hips and valleys in the roof you make it much more difficult to properly insulate a house. But all hope is not lost! Just make sure to meticulously detail the transitions between the new and old work. You said 2" or 4". DOn't screw around. If you're going to do it you should do it right the first time and go for 4". And a rain screen is a must for this kind of thing. Not only will your siding and pain job last longer (some studies I have seen suggest that a paint job will last as long as 15 - 20 years) you will also give some capacity to the wall to dry to the exterior, which you are throwing away almost completely with a vapor impermeable sheathing. Best of luck!

11-19-11, 11:26 AM	#9
warmwxrules Helper EcoRenovator Join Date: Nov 2011 Location: La Crosse, WI Posts: 78 Thanks: 0 Thanked 3 Times in 3 Posts	SF- I agree. Its looking likely that I'll just do everything. My roof is a hip roof (not sure if that is typical for a ranch), but the house is basically a rectangle (the front juts out a few feet on one end in the front). I have 24" overhangs all the way around the house. That garage door I have looks like a huge leak source. I'm going to try to adjust today and see if i can fix some of the gaps. Part of me wants to replace with with a new insulated door, but the door is in very good shape. I once was offered an insulated door for nothing...ooops!