# Insulating garage for a woodshop



## logan.newman (Jun 14, 2012)

Hi all - I'm looking for advice and I can't seem to find any help here. I have a 22' x 23' unfinished garage that I am currently working on turning into a woodshop. It has 2x4 walls with a plywood exterior and moisture barier. The walls are 2x6's and are about 11 feet in length to center. I checked r-values for my area, and with the 2x4's the best i can really get (especially at an affordable proce) is r13. I'm hoping to put in a woodstove at some point to help with heat when i work in the winter.

My question deals with the roof and the spaces between the roof and walls. 
1. Should I use the r13 on the ceiling? Does it go right up to the roof vent and then leave that open?

2. Can I spray foam sealant into the crevices between the walls and the roof joists? Will that cause issues for venitlation?

3. Can I get the foam board for the ends of the roof (where that big space is that is only covered by plywood), or should I cover that in the rolled insulation too? 

Thanks for your help!


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## packer_rich (Jan 16, 2011)

Sorry, but your post says 2x4 walls, then 2x6 walls.Which one is it? Are you going to drywall the ceiling? If you don't need that space, the lower ceiling means you could use blown in insulation, and you have less space to heat. that will also mean there is no need to insulate the gable ends. Don't block the space above the wall, you need the ventilation.


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## logan.newman (Jun 14, 2012)

Sorry - the walls are 2x4's and the ceiling trusses are 2x6's. the 2x6's overhand the walls and the soffit has lots of light and air passing through. What can I do here for heat?

I am not making an attic space as i want the space of the ceiling to hang lights and my air filter and the joists themselves are only about 7.5' off the floor. If i leave the gable ends bare what should i use to cover them to minimize heat loss? 

Thanks again


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## wkearney99 (Apr 8, 2009)

Pictures would help, a lot.

The roof needs to breathe. Air has to be able to come up from under the side soffits. This then travels up along under the roof and then out through the top center vent. When you enclose the space below you need to make sure the roof still breathes this way. 

If you want better wall insulation then you could simply stud-out the walls to give you greater depth for insulation. This would also give inset the ends of the rafters a bit to aid insulating without blocking the soffit ends. Same thing with the ceiling. Otherwise you'd have to look at using a spray foam insulation that would turn the whole space into a warm zone.

Don't know that I'd go with a wood stove in a wood shop. Just make sure that dust collector/air handler really does a good job of getting all wood dust out of the air. And be sure to put in at least one carbon monoxide sensor. You don't want to have fumes leak, build up and kill you.


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## logan.newman (Jun 14, 2012)

It would be cost prohibitive for me to stud out the walls. I think i will be fine with the r13 and wearing a sweatshirt if i need to. I'm more concerned about the best way to do the attic. Can I put the r13 on the underside of the roof and push it towards one of the joists to allow air flow to the ridegeline? What should i do on the open gable side? Can/should i use foam board? Can/should i stick with the r13?
thanks


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## wkearney99 (Apr 8, 2009)

You have to leave an air gap under the roof to allow it to breathe. Usually done with baffles from the soffits to the ridgeline (assuming there's a ridge vent there).


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## Evstarr (Nov 15, 2011)

Which means that in order to retain your heat you will need a finished ceiling. Either vaulted or flat but the underside of the roof deck needs air flow. So one choice is a flat ceiling below on the bottom chord of the trusses or a vaulted ceiling of maybe 2" foam board covered with drywall (the foam has to be protected from fire in a habitable space)


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## Centex2011 (Dec 14, 2011)

Although I cannot help with the insulation issues, I will say about the wood stove, my father-in-law couldn't put one in his wood shop due to insurance reasons. He said insurance would not cover the shop if he had a wood stove in there. That might be something to consider as far as the insulation. That was in Missouri, not sure if that would be a problem where you are.


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