Metal coop and roof insulation questions

[momma's chickens]

I have a metal shed and I have quite a fair amount of condensation on the inside of the roof. I want to put up insulation and I figure that foam board stuff would be a good choice. Do I need to to put a plastic sheet on first or can I just stick up the foam board. I am also going to paint the outside of the roof with a sealer.

I have been reading on here for over an hour and found tons of info but not answers to these questions.

Thank you

 

[cjeanean]

Hmmm, I don't know...I don't even know if insulation would solve the problem. I would think you would still have moisture between the roof and the insulation which would eventually mold and mildew and cause problems. I don't know, though, hope someone else can help!

 

[momma's chickens]

That is what I was afraid of that I would just be trapping in the moisture, hmmmmmmm?

After reading Pat's ventalation thread I will be adding some more vents tomorrow, but was still wondering about insulation.

 

[orbirdman]

heat rises, when it makes contact with a cooler area the moisture in the area will condense. im sure there is a better explanation but thats my understanding. if you were to insulate with out properly venting the area you will still have a problem IMO.

 

[Home on the Stead]

Moisture is a ventilation issue if the inside humidity is greater than the outside humidity. It is also an insulation issue as moisture will condense on cool surfaces. Metal roofs will have a great deal of temperature variation because they conduct heat so well.

Insulating your metal roof will reduce the condensation by equalizing the temperature of your roof with the air in the coop.

But...

Moisture on the insulation will eliminate it's insulation value. So typically you put the insulation under the roof, cover the insulation with a vapor barrier, and then sheet the inside (assuming your not going to have an attic space.)

So your layers are:

Outside Air
Roof
Insulation
Vapor Barrier
Sheeting
Inside Air

Hope this helps. I recommend a google search on insulating a metal roof - there are a lot of good how-to sites out there. For a good book on standard construction and the why's of it all I recommend "Building Construction Illustrated" by Francis D.K. Ching.

Good Luck.

 

[Mahonri]

What Home Stead said... and I would not only paint the outside with a sealer, I'd also put on a good coat of light/white paint that would reflect the effects of the sun.

 

[patandchickens]

Yes, just glue rigid foamboard panels up there and you will fix 95-100% of the problem. The reason you are getting condensation and drips is because the warm moist coop air near the ceiling is contacting the cold metal and condensing. Prevent that by installing yer insulation board and the problem goes away. (Unless, like many horse barns I've known, you have the occasional nail protruding down from the roof thru the ceiling, then you get weird one-point drips and frost stalactites in winter

)

You do not need to worry about installing a separate vapor barrier; foamboard is essentially a vapor barrier in and of itself. You do need to make sure it is cut pretty snug between your rafters or trusses so there aren't areas of exposed metal. Also, moisture does not affect the insulation value of rigid foamboard.

No moisture is going to be trapped anywhere, assuming you've done the installation properly. People have been doing this with metal-roofed buildings for years and years, honest, it works fine

The only caution is that rigid foamboard offgasses very toxic fumes in a fire (hence in houses it is generally required by code to be covered by something at least slightly fire-retardant, like drywall). But frankly, in a coop, if you have any combustion going on at all, you're probably going to lose your chickens, totally irrespective of whether you've got exposed foamboard insulation, so I would not personally worry about that.

Good luck, have fun, (and of course more ventilation prolly wouldn't hurt either

),

Pat

 

[bills]

Patandchickens post answers the issue, of your roof problem. You could use one of those spray can foam insulation products to fill any gaps between the board insulation, and around the edges.

You will still have condensation forming on the walls, but this is where the ventilation factor can play a roll. You will need more than the average coop anyway, especially during hot weather. The lighter color roof, and sides would be a definate benefit. You could insulate the walls as well, and then cover it with plywood, expensive, but the long term result may be worth it. The coop will stay a lot warmer in sub-zero temps, and a lot cooler in the summer.

I don't think metal sheds are the best hen house, simply because of the hot/cold issues, although they do offer other advantages.
JMHO.

 

[momma's chickens]

Bills, you are probably right they are probably not the best hen house, but it was available. I will most definitely look into the cans of foam to fill the cracks today. I am going to the Home "DePotty" as we call it today.

Pat, thank you so much for answering my question, I will do more vents and the foam insulation.

Home on the Stead, I will do another google search, I did one last night but used "insulating the roof of a metal chicken coop".

Mahonri- I will paint the roof with that reflective paint, do you think I need to paint it again over that I thought that paint was silver or white.

Thank you all I am now heading in the right direction and will let you know how it turns out.

 

[patandchickens]

Make sure you use an adhesive that is labelled as ok to use with foamboard. Some are, some aren't (the solvent in the wrong kinds of glue can sort of dissolve/weaken the foam).

Have fun,

Pat