# Insulating/venting shed



## Nealtw (Jun 22, 2017)

Will you be cooling or heating the shed.


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## Bud9051 (Nov 11, 2015)

Hi Kunkel and welcome to the forum.
If you add drywall across the bottoms of those ceiling joists then you do not want the insulation in the rafters. A standard approach would be to move that insulation down to the ceiling and then create some ventilation for the attic space above. There is not a lot of room up there and I doubt you will need to meet local energy codes for this small space but as much as reasonably possible would be good. Soffit vents for low venting and ridge or gable vents for high.

Bud


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## Kunkel19 (Aug 9, 2017)

Nealtw said:


> Will you be cooling or heating the shed.


Good question. In the coldest months of winter, I will be using an oil-filled space heater.

Joe


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## Kunkel19 (Aug 9, 2017)

Bud9051 said:


> Hi Kunkel and welcome to the forum.
> If you add drywall across the bottoms of those ceiling joists then you do not want the insulation in the rafters. A standard approach would be to move that insulation down to the ceiling and then create some ventilation for the attic space above. There is not a lot of room up there and I doubt you will need to meet local energy codes for this small space but as much as reasonably possible would be good. Soffit vents for low venting and ridge or gable vents for high.
> 
> Bud


Thanks for the response and welcome, Bud.

Is the venting going to be more about moisture or energy codes? Would I need to do BOTH ridge venting and soffit venting? Attached is what the eaves look like. The soffit venting might look like something in the second picture, yes?


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## Nealtw (Jun 22, 2017)

Kunkel19 said:


> Good question. In the coldest months of winter, I will be using an oil-filled space heater.
> 
> Joe


If you are not adding heat or cooling insulation is a waste of effort.

I would pull the insulation and make sure you have venting under the eaves on both sides. If you can't get venting at the ridge then second best would be a small vent one each gable end. Lay non papered batts across the joists and then the paper faced between the joists. In order to stop the insulation from blocking the vents at the eaves you would need chute stapled to the roof sheeting.
http://www.homedepot.com/p/ADO-Prod...t-Attic-Ventilation-System-UPV14480/100533902

That will save you a few degrees in summer and really help in the winter.
When you do drywall it will want to be taped filled and painted to keep moist out of the attic,


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## Kunkel19 (Aug 9, 2017)

Nealtw said:


> If you are not adding heat or cooling insulation is a waste of effort.
> 
> I would pull the insulation and make sure you have venting under the eaves on both sides. If you can't get venting at the ridge then second best would be a small vent one each gable end. Lay non papered batts across the joists and then the paper faced between the joists. In order to stop the insulation from blocking the vents at the eaves you would need chute stapled to the roof sheeting.
> http://www.homedepot.com/p/ADO-Prod...t-Attic-Ventilation-System-UPV14480/100533902
> ...


Thanks for all the info! If the insulation isn't wet or crushed at all, do you think I could reuse it?

Joe


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## Nealtw (Jun 22, 2017)

Kunkel19 said:


> Thanks for all the info! If the insulation isn't wet or crushed at all, do you think I could reuse it?
> 
> Joe


Let it dry if it is wet. Just throw it out in the sun for a few days.It is just glass.


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## Bud9051 (Nov 11, 2015)

Venting the attic space is about moisture. During cold conditions any air that seeps through to that space will find a cold roof and form condensation/ice.

You would want some of each, high and low venting. I don't think the normal rules apply as no showers, large gatherings, cooking (minimal), and other normal moisture sources so some venting is probably close enough.

Is that heater you are considering vented to the outside. Being a combustion appliance it will also need combustion air coming in. If well insulated electric heat might be more appropriate for that size space.

Bud


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## Kunkel19 (Aug 9, 2017)

Bud9051 said:


> Venting the attic space is about moisture. During cold conditions any air that seeps through to that space will find a cold roof and form condensation/ice.
> 
> You would want some of each, high and low venting. I don't think the normal rules apply as no showers, large gatherings, cooking (minimal), and other normal moisture sources so some venting is probably close enough.
> 
> ...


It's one of these jobbers in the picture below. I don't think combustion is part of it. Maybe I misnamed it?

I have a working wall mounted electric heater I was considering actually...


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## Bud9051 (Nov 11, 2015)

If the one pictured is oil filled electric that would be fine, the oil adds mass to release the heat at a slower rate. But ant electric heater would be fine. Let the hot air blow through a stack of bricks and you have the mass advantage. The key is, for a small space you don't want any combustion.


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## Kunkel19 (Aug 9, 2017)

To help me with my understanding, could someone please explain why it would not be good to put up drywall and just leave insulation in rafters?

Thanks, 
Joe


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## Bud9051 (Nov 11, 2015)

Small amounts of moisture are still going to move through drywall due to its permeance. Same reason food products get freezer burn when wrapped in plastic, the moisture can move through it. With fiber insulation it traps that moisture and creates the conditions necessary for mold. Different type of ceiling but same results pictured in this link.
http://www.greenbuildingadvisor.com/blogs/dept/musings/how-build-insulated-cathedral-ceiling

Bud


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## Kunkel19 (Aug 9, 2017)

Bud9051 said:


> Small amounts of moisture are still going to move through drywall due to its permeance. Same reason food products get freezer burn when wrapped in plastic, the moisture can move through it. With fiber insulation it traps that moisture and creates the conditions necessary for mold. Different type of ceiling but same results pictured in this link.
> 
> Thanks again. So I thought there was Ridge venting because of foam I saw under cap. When I took the cap off, I found this (picture). To make this an actual vent, do I need to saw a hole through this black paper to the open air in the attic below?


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## Bud9051 (Nov 11, 2015)

If there was an actual ridge vent over that and it was intended to be ventilation and not decoration then the black paper, underlayment, should probably have been cut away to permit air flow. I hedge a little as this is a shed and hard to be positive from my chair.

Bud


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## Kunkel19 (Aug 9, 2017)

Bud9051 said:


> If there was an actual ridge vent over that and it was intended to be ventilation and not decoration then the black paper, underlayment, should probably have been cut away to permit air flow. I hedge a little as this is a shed and hard to be positive from my chair.
> 
> Bud


Thanks one more time for all the help you're offering. I really appreciate you and this forum.

The shed was originally sort of storage area that has been slowly added to by the previous owner and myself. If I had to guess, I would suppose that it is not officially vented. The foam pieces that lie between the ridge cap and the roof sections are not perforated and the gap between the meeting roof pieces does not always have the gap pictured. In many places there is virtually no gap.

That being said, to make this a legitimate roof vent, could I cut through the underlayment (it's very easy to get through), replace the solid foam with a vented foam material and reattach the cap? Do you think that would be acceptable? If so, how wide should the gap in the underlayment be and for what length of the roof should it be cut?

Or would it be better to go with gable vents?

Thanks a million, 
Joe


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## Nealtw (Jun 22, 2017)

Kunkel19 said:


> Thanks one more time for all the help you're offering. I really appreciate you and this forum.
> 
> The shed was originally sort of storage area that has been slowly added to by the previous owner and myself. If I had to guess, I would suppose that it is not officially vented. The foam pieces that lie between the ridge cap and the roof sections are not perforated and the gap between the meeting roof pieces does not always have the gap pictured. In many places there is virtually no gap.
> 
> ...


Usually an inch on each side of center or if there is ridge board in the way 1 1/2 - 2 inches on each side


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## Kunkel19 (Aug 9, 2017)

Nealtw said:


> Usually an inch on each side of center or if there is ridge board in the way 1 1/2 - 2 inches on each side


So I would set a circular saw to go through the underlayment and sheathing, measure out from both sides of the ridge, cut most of the length of the roof, leaving some room at either end, lay down something like this:

http://www.bestmaterials.com/detail...lLnyxcqZ7QoswIoochFIu79kh9W2Y4ThoChaMQAvD_BwE

And screw the cap back on? Is that correct?

Is this more or less work/money than gable venting?

Joe


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## Nealtw (Jun 22, 2017)

Kunkel19 said:


> So I would set a circular saw to go through the underlayment and sheathing, measure out from both sides of the ridge, cut most of the length of the roof, leaving some room at either end, lay down something like this:
> 
> http://www.bestmaterials.com/detail...lLnyxcqZ7QoswIoochFIu79kh9W2Y4ThoChaMQAvD_BwE
> 
> ...


Yes..............:vs_cool:


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## AIRLOCK (Jun 19, 2017)

Kunkel19 said:


> To help me with my understanding, could someone please explain why it would not be good to put up drywall and just leave insulation in rafters?
> 
> Thanks,
> Joe


if you drywall the sloped ceiling then you could leave the insulation, but because you are planning to drywall the flat ceiling, you would create a dead air space that is not conditioned. this will cause convection to occure and will eventually warp and discolor the drywall.

i would pull the fiberglass out and dense pack celllulose in the flat ceiling and then drywall. you can net the ceiling before you blow the ceiling and then hang the drywall over that.

cellulose is 90% sound deadening as well. i used it in my band spot in my 20's. kept the police from ticketing us for noise violations.

Joseph

www.AIRLOCK-Insulation.com


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## XSleeper (Sep 23, 2007)

I agree with Airlock regarding where the insulation should be... between the ceiling joists... and in addition think that for a shed, gable vents would be preferable. If you have a ridge board, it doesn't look like you have 3" between your metal roofing anyway... and removing the foam closure to allow ridge ventilation could allow wind blown rain and/or snow in. Just a thought.


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## AIRLOCK (Jun 19, 2017)

XSleeper said:


> I agree with Airlock regarding where the insulation should be... between the ceiling joists... and in addition think that for a shed, gable vents would be preferable. If you have a ridge board, it doesn't look like you have 3" between your metal roofing anyway... and removing the foam closure to allow ridge ventilation could allow wind blown rain and/or snow in. Just a thought.


yes! great point.

Gable vents are cheap and easy to install and will help prevent problems such as condensation and overheating in the attic. this will help it last a lot longer by not warping and wetting the attic space. that is why ventilation is necessary. In my opinion

Joseph

www.AIRLOCK-Insulation.com


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## AIRLOCK (Jun 19, 2017)

Kunkel19 said:


> So I would set a circular saw to go through the underlayment and sheathing, measure out from both sides of the ridge, cut most of the length of the roof, leaving some room at either end, lay down something like this:
> 
> http://www.bestmaterials.com/detail...lLnyxcqZ7QoswIoochFIu79kh9W2Y4ThoChaMQAvD_BwE
> 
> ...



cutting out the ridge for installing a vent is a good idea, it is more work than installing gable vents, and you have to go up on the roof. but can be very effective for adding air flow. 

Joseph

www.AIRLOCK-Insulation.com


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## Nealtw (Jun 22, 2017)

AIRLOCK said:


> if you drywall the sloped ceiling then you could leave the insulation, but because you are planning to drywall the flat ceiling, you would create a dead air space that is not conditioned. this will cause convection to occure and will eventually warp and discolor the drywall.
> 
> i would pull the fiberglass out and dense pack celllulose in the flat ceiling and then drywall. you can net the ceiling before you blow the ceiling and then hang the drywall over that.
> 
> ...


Care to explain how you get a dead air space above a flat ceiling when you have ridge vents and what does that have to do with fiberglass?


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## AIRLOCK (Jun 19, 2017)

Nealtw said:


> Care to explain how you get a dead air space above a flat ceiling when you have ridge vents and what does that have to do with fiberglass?


sure. thanks for asking that question.

IF Ridge vents are installed, or gable vents are installed to where there is adequate ventillation, then there would not be dead air space. 

leaving the existing insulation is not the best, because it can cause dead air space can and does happen if baffles (air vents) are not installed. i would remove the fiberglass to eliminate the condensation that will ocure between the fiberglass and the sheathing.

also if the fiberglass is removed, you can see the under side of the roof if there is ever a leak. you can pin point it easier. small detail but i like to see the attic roof if possible.

i hope this makes sense. let me know if i can clarify better.

Joseph Wolf
www.AIRLOCK-Insulation.com


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## Nealtw (Jun 22, 2017)

AIRLOCK said:


> sure. thanks for asking that question.
> 
> 
> Joseph Wolf
> www.AIRLOCK-Insulation.com


Thank you; I miss read the other post. Oops


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