Insulating detached garage

[Sh40674]

Ok keep in mind 2 things...
1. Answers in stupid English are appreciated.. I'm not super skilled in the insulation and construction terms.. Please bear with me
2. Not looking to spend a lot of money at all.

Detached garage

So here is my question.. After winter I am looking to insulate my garage for next winter (hope to heat it) it is detached and the goal is to keep it about 42-45 degrees all winter so my stuff don't freeze.. And a little warmer (50s-60s) when working out there. It's approx 28x28 or so. Has OSB walls and ceiling with a pull down attic ladder so I can store everything above the ceiling. What type of CHEAP roll insulation do I want behind the walls? Our local menards regularly has rolled insulation with one side that's paper on sale for 5-6 bucks a roll or so. Will this work? Which side faces in? And do I have to worry about moisture or just roll it between the studs and put the walls back up?

Do I need a vapor barrier? I know a lot of guys that just put in insulation then walled it back up with drywall or OSB. I can see the need in a house... But the garage?

For the ceiling... Can I just put like a cheap rigid foam or something or what would I want to use above the ceiling?

Thanks in advance. Like I said just looking to do this quick and cheap. Not looking for an 80degree garage.. Just to keep above freezing.. Say 45 and 60 when I'm working in there.. Maybe a tad warmer if I throw a party

 

[soapii]

The paper on the rolls is the vapor barrier. Paper faces the inside of the garage.

If you are deciding where to spend your money I would put more into the ceiling and less into the walls. Heat rises, you lose most of your money through the roof. Put rigid foam in the walls and better insulation in the attic.

People don't put up OSB or drywall as a vapor barrier, they do it to finish the interior walls.

--Joe

 

[jkrswld]

My previous garage was a 2.5 stall, probably similar size to yours. I got some free insulation from a friend's uncle who tore down some interior walls in an office building when he expanded. Anyway, I had enough of the roll type with the paper to do my walls and ceiling with it. Not sure what R value it was, but it was the 3.5" kind that you're probably seeing go on sale all the time.

I did NOT do an extra vapor barrier, and I put OSB up on the walls and painted it. I never got around to finishing the underside of the ceiling though. Above the ceiling insulation I threw down some thick OSB so I could walk around up there.

I'm not a pro and pretty much winged it. But, that garage didnt freeze any more and that was without heating it. It probably got down to below 32 sometimes since I'm in WI - but, it wasn't enough to regularly freeze bottled water or anything. It held heat pretty nice when I fired up my propane heater.

i believe the proper way to do things is the insulation in ceiling FIRST, since heat rises. The thicker the better as long as you're not crunching it down, as then it'll lose the insulation value. Buy the tallest you wish to spend money on, so long as you're not having to pack it all down to make it fit. Same deal on the walls. Then, you'd consider using vapor barrier/plastic on all the surfaces, though I've read many folks just consider the paper facing to be "just fine" as is.

I cut those corners on mine (no vapor barrier, didn't finish off ceiling) because I did not feel it likely that i would develop mold or moisture issues. I was willing to risk having to drop the OSB and remove the insulation if needed - because I had gotten it for free so I figured either way I'm already coming out on top.

Hope my rambles help

 

[Sh40674]

For above the ceiling... Paper facing the roof or floor? Or would the insulation with no paper work?

 

[soapii]

For above the ceiling... Paper facing the roof or floor?

Yes you want paper and like i said in my previous post, paper faces the inside.

--Joe

 

[Sh40674]

So if I were to walk on it I would be walking on the fiberglass side? I understand about facing twords the floor but I just figured the paper would go on the exposed (roof) side

 

[soapii]

So if I were to walk on it I would be walking on the fiberglass side? I understand about facing twords the floor but I just figured the paper would go on the exposed (roof) side

You figured wrong

And I would not suggest walking on the insulation, that's a good way to put your foot through the drywall. Walk from roof truss to roof truss.

--Joe

 

[jrfiero]

Vapor Barrier

If you don't have any moisture generation in the garage you don't need a vapor barrier. A house has bathrooms and kitchens with water, and any combustion appliances generate moisture.

Buy whatever you can get that's cheapest (foil faced, craft faced, or unfaced), but don't go by the cost per roll - check the cost per square foot. Rolls come in different sizes. You can also buy batts rather than rolls (the batts will probably be rolled up).
Vapor barrier, if you use it, always faces the "living" area.
As others have said, go for the ceiling first, that's where you get the most bang for your buck, and don't put only 3 1/2 inches up there. Just fyi, current code is R-38 for ceilings in dwellings. The amount will partially depend on your joist/truss depth if you have a floor up there or don't want to build up the joists before installing a floor.
You do need to cover the insulation in the ceiling, either above or below, preferably both, because fiberglas insulation with air moving through it is practically useless.
You mention cheap rigid foam - is there such a thing? Rigid is expensive, and difficult to properly fit.
Don't cheap out too much - insulation will pay you back forever.

Jonas

 

[Fun pain]

How are you guys answering Vapor barrier questions for a garage without knowing where this person lives? Or how he plans to heat it.

HEAT DOES NOT RAISE

warm air (less dense) wieghs less then cold air (more dense).... (gravity)


If you have more surface area on the walls then ceiling you will be loosing most of your heat through walls.... you didn't tell us how tall the garage is. If you do a heat loss calculation, (can't attach one, i would if I could). Windows and doors could be more important then the ceiling, as long as it is air tight.

Leaks will cheat insulation, almost everytime

Your not going to get "Good" information on this forum, without giving lots....

I usually do not complain about the use of paper faced, because it ***** as a vapor barrier at least everyway I have seen it installed. If you use it the only real benefit is the ease of install. Your not sealing/barriering anything really. I would call it a Vapor Retarder or permiable.

 

[OccupantRJ]

If your walls are already up, consider using a hole saw at the top of the wall into the stud cavities, then use blown in insulation to fill the cavities. A trim board can be used to cover the holes. As someone else said, calculate your cost per square foot to end up with useable comparisons.

 

[Sh40674]

8ft high ceiling with OSB covering the ceiling as well. Most moisture in the garage would be from summer heat (live in iowa)

 

[jrfiero]

How are you guys answering Vapor barrier questions for a garage without knowing where this person lives? Or how he plans to heat it.

HEAT DOES NOT RAISE

warm air (less dense) wieghs less then cold air (more dense).... (gravity)


If you have more surface area on the walls then ceiling you will be loosing most of your heat through walls.... you didn't tell us how tall the garage is. If you do a heat loss calculation, (can't attach one, i would if I could). Windows and doors could be more important then the ceiling, as long as it is air tight.

Leaks will cheat insulation, almost everytime

Your not going to get "Good" information on this forum, without giving lots....

I usually do not complain about the use of paper faced, because it ***** as a vapor barrier at least everyway I have seen it installed. If you use it the only real benefit is the ease of install. Your not sealing/barriering anything really. I would call it a Vapor Retarder or permiable.

I don't think this is a very accurate post.
You say hot air rises above cold air, but also say heat doesn't raise (sic). That's tivial semantics, and the difference doesn't matter
.
Your comment about square footage of walls and ceiling is not true. Almost all rooms/enclosed spaces have greater wall area than ceiling area yet the general understanding (as evidenced by code requirements) is that a space loses the most heat through the ceiling.

Even if a poster does give "good" information he sometimes won't get "good" information back.

 

[dave67fd]

Although you loose most of your heat through the ceiling, having uninsulated walls just allows more cold to enter. If you do one you need to do the other period.

 

[Fun pain]

I don't think this is a very accurate post.
You say hot air rises above cold air, but also say heat doesn't raise (sic). That's tivial semantics, and the difference doesn't matter

This is not trivial because tons of people have this mindset that HEAT rises and it doesn't.
Heat goes to cold, that is the simplest way to say it.

Examples: Radiator in your car or truck.
All refrigeration works on this principle.
Frozen lakes.

This is physics. Not an opinion.

If he or she puts R-1000 super duper insulation in the ceiling.

With walls made of "Low E" double hung windows perfectly sealed. (R-2 by the way, maybe R-3 if you spend alot of money)

All HEAT will go to the windows, kind of a waste of money and super duper insulation.

Sadly this happens often, way to often.

Code requirements are very political and are a very broad, general guideline. It is usually easier to add lots of insulation into the attic without taking up space, or having to upgrade building materials dimensions (2x4 to 2x8).

 

[Fun pain]

Heat Loss Calculators

http://www.builditsolar.com/References/Calculators/HeatLoss/HeatLoss.htm


here is a pretty good one, from builditsolar.com

There are lots of these online. Make somethings up, or try to replicate your building in the data slots.

if you have excel and know how to use it. Use this one (below).... I like it

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=9&cad=rja&sqi=2&ved=0CHoQFjAI&url=http%3A%2F%2Fwww.crownboiler.com%2Fdocuments%2Fsupport%2Fheat_loss_calculator.xls&ei=-j3UUqTXH8SRrgGx-4AI&usg=AFQjCNEtPIj-W3Ods821Sg9jJqbs5VgiOA&sig2=1K-RKZRlCe6Wgn2nEvYvPw

 

[harley jim]

sh40674
I lived in Montgomery il. most of my life I had about the same climate you have to deal with. I had regular 3.5 insulation in the walls, also I did not have a vapor barrier as I didn't have any water/moisture in the garage. Most of the insulation I had was reclaimed from old houses being torn down, I did not spend any money inside my walls. I got a load of paneling from a remodel job done on a basement, it didn't cost anything.
I used plywood that I got from work to cover the ceiling with, I went to menards and bought blown in insulation and they loaned me a machine to blow it in, spent 150 or 200 on this not sure was a long time ago.
I had a small wood burner to heat with, neighbor was a tree man and kept me in wood.
My garage was 24x26 with 8 ft. walls and a full 17 ft solid garage door no windows.
It stayed 70 deg. all winter, I was able to work in a t-shirt all winter. There are as many ways to insulate a garage as there are people on this site DON"T KNOW IF I DID IT RIGHT but it worked for me for 27 years. I hope this helps answer some of your questions

 

[Fun pain]

Yeah if you want to cut down and burn a forest to heat your garage you don't need any insulation at all.

Seal her up and keep throughing wood..... until its warm


My dad's old friend used to heat a huge metal building, with a wood stove big enough to roll a semi's tire in it. (he had lots) I remember it being 10-20 outside and 90 degrees inside.... just keep rolling tires in.... that burner was glowing.

I'm saying like 3 full sem's inside with trailers and still park like 8 cars or trucks in it.


Which does bring up a point,

Sh40674

What are you heating with?
What do you want to heat with?
What do you want to spend a month on fuel? (electric, gas, wood, beer farts)


Maybe that will help us, Help you.

 

[CNGsaves]

OP, you would be smart to listen to Fun Pain . . . . he KNOWS what he's talking about !!

For lowest cost, blown in cellulose insulation would work. However, need to spend time and effort first closing up leaks with foam around windows, doors, outlets, cracks, etc. Good luck.

 

[Stevie-Ray]

In loose English, heat rises and falls.

Here's a pretty good explanation.

http://www.energyvanguard.com/blog-...and-Falls-Stack-Effect-Air-Movement-Heat-Flow

Any insulation is better than none. Just the walls are insulated in my garage, so far, and it's already warmer or colder than the outside at any given point, telling me it's better than when uninsulated, and prone to wild temperature swings. Of course, I'll be doing the ceiling as well, as money permits.

 

[Sh40674]

I'm gonna be using a natural gas heater.. Big max, hot dawg, beacon morris, etc.. The plan is for next winter to be ready. I'm going with r13 in the walls and ceiling and I crawled up there and realized that its all 2x4 construction for the ceiling..

 

[mygarageone]

One thing I highly disagree with , I would never insulate any building with out a

( Vapor Barrior ) Never ! Because someday your going to heat ,right ?

So , if you really are looking to save money put up non faced insulation and cover the walls and ceiling with visqueen ( plastic ). This will give you a tighter building and a vapor Barrior.
Forget this stuff that a garage will have no moisture , trust me it's In the air you breath ,so it will be in the Garage too. And when that warm MOIST air hits that cold outside wall ,what do you think you'll have ? Yep condensation , Then mold build up , then rotted wood , then Thousands of dollars in repairs.
A little money now saves thousands later !

 

[Average_Joe]

I'm going with r13 in the walls and ceiling and I crawled up there and realized that its all 2x4 construction for the ceiling..

Use no less than R30 in the ceiling. You can let the batts stick up past the framing/trusses. Or you can have 12" blown in, that should be cheaper.

 

[Sh40674]

I'm not getting rid of my storage space

 

[toyotadriver]

Absolutely correct that heat moves to cold.

However, if hot air doesn't rise, then explain how a hot air balloon works.

 

[Fun pain]

toyotadriver.... read my post again.... YES, Warmer AIR rises above colder air (gravity)

That is why a Hot Air Balloon works at all. Think about why it comes down...LOL


mygarageone... HOLLY ****, you are way north. (of me anyways).... Vapor barrier in your case would probably be a good Idea. Here in the middle of Ohio, we cool just as much as we heat to a vapor barrier on the inside would be a issue in the spring,summer, fall. For a garage without an air handler, vapor barriers will cause issues. And I dont' know if you know this,(but I will mention it), if you move to the south, you want the vapor barrier on the outside. Because it is cooler inside then out most of the time......

Your policy in your area is probably a good one. BUT
Don't treat it so black and white on an internet forum. Its not.

YOU ARE MORE North then most Canadians!!!

 

[mygarageone]

toyotadriver.... read my post again.... YES, Warmer AIR rises above colder air (gravity)

That is why a Hot Air Balloon works at all. Think about why it comes down...LOL


mygarageone... HOLLY ****, you are way north. (of me anyways).... Vapor barrier in your case would probably be a good Idea. Here in the middle of Ohio, we cool just as much as we heat to a vapor barrier on the inside would be a issue in the spring,summer, fall. For a garage without an air handler, vapor barriers will cause issues. And I dont' know if you know this,(but I will mention it), if you move to the south, you want the vapor barrier on the outside. Because it is cooler inside then out most of the time......



Your policy in your area is probably a good one. BUT
Don't treat it so black and white on an internet forum. Its not.

YOU ARE MORE North then most Canadians!!! [/QUOTE

Here's the deal , as far as a vapor barrier goes there isn't a builder worth his salt ,who says we don, t need one. Any time you have a heated space against a cold wall , you had better have a vapor barrier.
I have seen the results in a home that was insulated with out a vap barrier. Black mold, rotted wood , etc,etc.

 

[Fun pain]

You do realize that everyone that has build a house or a garage with kraft faced fiber glass has not used a vapor barrier......

http://www.buildingscience.com/documents/reports/rr-0412-insulations-sheathings-and-vapor-retarders/view?searchterm=vapor


If you read this pdf from the BSC you will see that all "kraft facing" considered to be vapor semi-permeable. It is not a barrier, osb does as good of a job at being a barrier.

I believe if you read the climate differences you will see my point.


This article below. Shows the problem with you saying that online....lol, It talks specificly about cold region build practices be used in lower regions cause lots of damage and cost issues....

http://www.buildingscience.com/documents/information-sheets/vapor-open-assemblies/?searchterm=vapor



Here's another that explains more of vapor and show why not to use it in zone 5 and NON of the examples use a vapor barrer on the inside (all are vapor retarders or semi-permeable)

http://www.buildingscience.com/documents/reports/rr-0410-vapor-barriers-and-wall-design

I wouldn't hire any of those "Salts", you speak of.....

Do I need more proof?


one more.... read the last paragraph....

http://www.buildingscience.com/documents/information-sheets/info-sheet-310-vapor-control-layer-recommendations/?searchterm=vapor

 

[2CRUZ]

What is the big deal. Just do like I did in my new 30x40 Insulate the walls and celing paper side in and put up plastic on the walls and celing. then sheet rock over that. The plastic doesn't coast that much anyway. I walk in turn up the natural gas furnace and in 5 mins. it's warm as toast. I think you guys are makeing a bigger deal out of it than it is. By doing it that way you have all your bases coverd and if it isn't right you be dead and gone before you notice it anaway.

 

[Fun pain]

2CRUZ.... you need to read those links too then

 

[Fun pain]

Sh40674

Hopefully this will help you choose and insulation method and maybe your heat source.

using this.....http://www.builditsolar.com/References/Calculators/HeatLoss/HeatLoss.htm


28' x 28' x 8' building, with r-13 in walls and ceiling, I filled out nothing for windows or doors because I don't know what you have. .47 for concrete slab with no insulation, leaky (1.0 for Infiltration)..... over 25000 btu's per hour @ 25 degrees F (design outside temp), you can fill that out better then us. It will even give you fuel cost/savings.... Won't take you long.

After filling this out look at the graph.... most of your heat will be going to heat your.....

1st. Your concrete slab
2nd. Your infiltration (leaks, very small ones)
3rd. Walls
4th Ceiling

That's because I didn't add windows or doors.... NEED MORE IMPUT (says Johnny 5)

 

[frankush]

I'm gonna be using a natural gas heater.. Big max, hot dawg, beacon morris, etc.. The plan is for next winter to be ready. I'm going with r13 in the walls and ceiling and I crawled up there and realized that its all 2x4 construction for the ceiling..

If that ceiling is only 2X4 construction, I'd be real careful about how much weight you put up there. It will be sagging before you know it.

 

[Stevie-Ray]

Here's another that explains more of vapor and show why not to use it in zone 5 and NON of the examples use a vapor barrer on the inside (all are vapor retarders or semi-permeable)

http://www.buildingscience.com/documents/reports/rr-0410-vapor-barriers-and-wall-design

Interesting. So, if I'm reading that correctly, being in zone 6, I don't need to put plastic over my insulation inside my garage, before drywalling. Was going to ask my builder about that. I have Kraft-faced insulation up in the walls so far. Garage was built with OSB outside walls, Typar housewrap, and vinyl siding.

 

[frankush]

Lots of varied info in this thread. The trend these days is to minimize air infiltration and leakage. Plastic vapor barriers and caulking penetrations help to keep the warm air in. It's good practice and will help with the heating and cooling bill.

 

[Fun pain]

Frankush.... You need to read the links...

 

[Autorotica]

HEAT DOES NOT RAISE

Fun Pain,

If you don't mind the suggestion... Consider this modification to your statement.

Heat is energy. Energy goes from where it is to where it isn't. There is no up or down when it comes to energy.

Chris

P.s. Hot AIR always rises above cool air

 

[Fun pain]

I never mind suggestions at all...but

I am thinking that I am just wasting my time trying to give free engineering facts...

 

[Highbeam]

I never mind suggestions at all...but

I am thinking that I am just wasting my time trying to give free engineering facts...

Do you feel like you are constantly repeating yourself and that nobody is
"learning" ?

You might have noticed by now that many folks disagree with your facts and generalizations and it is not polite to correct others on a forum. Confrontational and we are allowing you your opinion.

Many of us are also engineers.

Myself, I see the plastic VB as an important air sealing feature more than a vapor barrier. Lots of energy is lost through air leaks.

 

[Fun pain]

So if I ask a question or create a topic.

And most of the answers I get are wrong or is going to cost me time and money.

Since I asked the questions? I probably don't know that they are bad ideas(thats why I asked).

No one should correct them? Or show evidence to the contrary?

If that is some kind of unwritten, rule that I don't know about at garagejournal.com....

I appologize.







Heres a few links for you HIGHBEAM... FEMA messes this up two...read and see

http://www.buildingscience.com/documents/insights/bsi-021-thermodynamics-its-not-rocket-science/?searchterm=vapor barrier

and Air Barriers Vs. Vapor Barriers
http://www.buildingscience.com/documents/reports/rr-0004-air-barriers-vs-vapor-barriers/view?searchterm=vapor barrier

 

[mygarageone]

Fun Pain,

If you don't mind the suggestion... Consider this modification to your statement.

Heat is energy. Energy goes from where it is to where it isn't. There is no up or down when it comes to energy.

Chris

P.s. Hot AIR always rises above cool air

Correct and because cool air is denser , warm air will always rise above it.

 

[mygarageone]

By the way Fun Pain.

Ohio is not really all that far south and it does get quite cold there , so I am. Sticking with my vapor barrier statement.