Faced or unfaced insulation??

[AllenB]

I've got a 2 car detached garage with a roof pitch of 8/12 (storage above). I plan on insulating the walls and ceiling with batts. Do I use faced or unfaced...and on both the walls and ceiling? They will be covered with OSB board. The garage does not have wrap on it and I'm located in Ohio.
Thanks!

 

[bczygan]

Faced.

 

[Falcon67]

Faced, facing inside. If nothing else, it's easier to install with facing.

 

[Cryptic1911]

use faced.. goes in easier, and you won't have fiberglass stuck to you from your asscrack to your ears

 

[MScott]

I disagree. I used faced insulation in an attic and found that, when I went in there several years later, the facing was brittle and tore very easily destroying the vapour barrier. I much prefer insulating with unfaced bats and then covering with plastic vapour barrier. If you don't like fibreglass, use Roxul insulation.....no fibres, better insulation and mice do not like it.

 

[ddawg16]

I disagree. I used faced insulation in an attic and found that, when I went in there several years later, the facing was brittle and tore very easily destroying the vapour barrier. I much prefer insulating with unfaced bats and then covering with plastic vapour barrier. If you don't like fibreglass, use Roxul insulation.....no fibres, better insulation and mice do not like it.

How NOT to do it.....

The vapor barrier HAS to go between the inside wall and insulation....otherwise you will trap the moisture in the insulation....which reduces it's R value....and can lead to mold.

What is not obvious is that a majority of moisture comes from inside the house....

Case in point....I have a 2-story garage....the second floor is mostly storage...but I made a small area for the kids and their toys....when they are up there playing....the moisture builds up so much that it starts to rain in there....moisture condenses on the ceiling and then starts to drop....one of my future projects is to install drywall on the ceiling....with the vapor barrier between the drywall and insulation.

 

[Greatwhitewing]

I've got a 2 car detached garage with a roof pitch of 8/12 (storage above). I plan on insulating the walls and ceiling with batts. Do I use faced or unfaced...and on both the walls and ceiling? They will be covered with OSB board. The garage does not have wrap on it and I'm located in Ohio.
Thanks!

BTW it's quite likely you can have the work done for the same cost as doing it yourself. Found that out to be true in MA.

When I did my last wall job I couldn't wait for a contractor and did myself using insulation withOUT a vapor barrier and made my own barrier from poly sheet. That way I could make it continuous all the way under the subfloor.

 

[Highbeam]

I much prefer insulating with unfaced bats and then covering with plastic vapour barrier.

I took this to mean that the poly was on the living side of the wall. Done properly.

I actually plan to do my walls this way because I want the superior seal that poly offers. Easier to cut to fill odd stud cavities without dealing with the facing.

In the attic, well, I believe that it is absolutely ridiculous to do anything but blown in loose fill insulation if you have attic access and no second story.

 

[Falcon67]

FWIW- I have found that a continuous barrier and sealed ceiling has less importance in a shop that is not continually heated or cooled and not occupied like a house. So look at the actual use and don't get too carried away.

 

[MScott]

I took this to mean that the poly was on the living side of the wall. Done properly.

In the attic, well, I believe that it is absolutely ridiculous to do anything but blown in loose fill insulation if you have attic access and no second story.

Yes, the poly should be on the living side at least in the north. As to the attic, my installation was in a knee-wall area, not in the floor/ceiling.

How NOT to do it.....

The vapor barrier HAS to go between the inside wall and insulation....otherwise you will trap the moisture in the insulation....which reduces it's R value....and can lead to mold.

What is not obvious is that a majority of moisture comes from inside the house....QUOTE]

I believe that is what I was saying.

 

[JasonW]

I think this is relevant.

I have a question for the poly guys. I understand about running the barrier behind the electrical boxes. I have seen guys cut a square of poly and nail the box through it. Then when the poly is stretched over the wall they cut for the fronts of the boxes, pull the initial poly square through and tape it back to the sheet. What I don't understand is the proper or preferred method for sealing that initial poly square around the wires that enter the box. Any thoughts?

 

[jkeyser14]

I think this is relevant.

I have a question for the poly guys. I understand about running the barrier behind the electrical boxes. I have seen guys cut a square of poly and nail the box through it. Then when the poly is stretched over the wall they cut for the fronts of the boxes, pull the initial poly square through and tape it back to the sheet. What I don't understand is the proper or preferred method for sealing that initial poly square around the wires that enter the box. Any thoughts?

You'll have holes, it's bound to happen. Unless its on a ceiling it will barely have any effect on air infiltration (we're talking about fractions of a CFM of air infiltration).

Besides, you really don't want the house to be too tight or you run into mold issues there as well.

 

[Angelfire]

For a shop, faced batts are probably easiest for the diy'er. That being said, I will be using unfaced for my new shop and an addition because I want the shop to be easily convertible to a living quarters for the next owner (as a selling point etc) and i'm getting better r value with the unfaced ones I'm using. Don't use poly. It's permeability is near zero perms which is great to keep water out, but it will also trap the water in. Find a vapor retarder such as asphalt impregnated paper or if you don't mind dropping cash, there are ones that adjust their permeability based on humidity. These will work better to ensure the wall dries out when it gets wet.

 

[joeysh03]

Bringing this tread back because I can't find my answer. I want to insulate my garage attic and find find the right answer. I currently have no insulation in my attic and it's not heated or cooled. Every now and then in the winter I use a torpedo type heater just to warm the space up fir 30deg to about 60deg and turn it off. Faced or unfaced is the question. Can only find answers related to condition spaces and my garage is not condition. I was thinking about putting r-13 unfaced in the joist cavitys and then r-30 unfaced ran perpendicular. Will this work???

 

[Crazyjake8493]

Faced fiberglass would be easiest to install, and would be an "ok" job. I always prefer Roxul and covering it with a poly vapor barrier for a better install. Roxul is far superior to fiberglass, but it does cost a little bit more.

 

[Elginz]

Faced and facing inside

When I built my garage I put insulation under the cement and in the walls, didn't heat it for years I did put poly on the ceiling before the OSB went up.
was like that for years maybe 15 years. Now I have the attic blown full (well almost) and heat it to about 65 degrees all winter. Plan ahead is what I am saying.
To answer your question, yes

 

[Jess]

I think this is relevant.

I have a question for the poly guys. I understand about running the barrier behind the electrical boxes. I have seen guys cut a square of poly and nail the box through it. Then when the poly is stretched over the wall they cut for the fronts of the boxes, pull the initial poly square through and tape it back to the sheet. What I don't understand is the proper or preferred method for sealing that initial poly square around the wires that enter the box. Any thoughts?

The most common way, other than the poly square, is to use vapour boots which are made for the purpose. A small slit through the boot for each wire run and seal that slit with acoustic sealant. Once the insulation and inside vapour barrier are installed, the poly is cut at the flange of the boot and sealed with another very small bead of acoustic sealant. Some use tape but I prefer the sealant. The secret here is not to use very much or its a mess and to seal all overlaps of the vapur barrier.

 

[ADSR]

The most common way, other than the poly square, is to use vapour boots which are made for the purpose. A small slit through the boot for each wire run and seal that slit with acoustic sealant. Once the insulation and inside vapour barrier are installed, the poly is cut at the flange of the boot and sealed with another very small bead of acoustic sealant. Some use tape but I prefer the sealant. The secret here is not to use very much or its a mess and to seal all overlaps of the vapur barrier.

We don't use poly on the island. If water gets in the wall, it will never dry out.

 

[Jess]

We don't use poly on the island. If water gets in the wall, it will never dry out.

You may not, but its required in the BC building code and would fail an inspection if you were building or renovating with a permit. If you don't use poly, what are you using for vapour barrier? If you have moisture build up in the wall, there is another issue beyond the vapour barrier. Don't confuse vapour barrier with rain screening, which is also in the BC Building code now. The issues with water and the 'leaky condo' fiasco are caused by sealing the exterior of the building envelope which was trapping moisture in walls. The vapour barrier is to prevent the moisture from the inside of the building from getting into the insulation and structure beyond. The structure should be designed to dry outward. Ventilation is also a requirement to overcome the 'sealed house' that has caused the problem in the first place. In the old days, there was enough air movement through the structure to carry off any excess moisture.

 

[ADSR]

You may not, but its required in the BC building code and would fail an inspection if you were building or renovating with a permit. If you don't use poly, what are you using for vapour barrier? If you have moisture build up in the wall, there is another issue beyond the vapour barrier. Don't confuse vapour barrier with rain screening, which is also in the BC Building code now. The issues with water and the 'leaky condo' fiasco are caused by sealing the exterior of the building envelope which was trapping moisture in walls. The vapour barrier is to prevent the moisture from the inside of the building from getting into the insulation and structure beyond. The structure should be designed to dry outward. Ventilation is also a requirement to overcome the 'sealed house' that has caused the problem in the first place. In the old days, there was enough air movement through the structure to carry off any excess moisture.

Yeah, I know it's code. Been building in victoria for over 10 years. Everytime I come across rott, it's because no air can get in to dry it out. After a poly inspection, a lot of contractors will ask the borders to slash the poly. I've even had home owners do it themselves. Also, I've done my fair share of rain screen. That's another joke, another story. Back in 08 I built all those west coast houses you see up on Christmas hill. They were all rain screen by then.

 

[Jess]

The issue of not using a vapour barrier is that considerable moisture from inside the house will condense in the insulation or framing. If you slash the insulation, then you would be adding to the issue. A properly detailed vapour barrier system will prevent interior moisture from entering into the insulation and framing. I have owned and retrofitted a number of properties in Victoria over the past 40 years and still have a few of them. The devil is in the details and many builders work to get it right. To each his own.