metal roof, snow concerns-update new roof design

[Rare Feathers Farm]

Here my coop. The roof slants towards the front of the coop (there are no runs in the front though). The front is the southern side. My coop is fully insulated, including the ceiling.

The downside to this design is that the snow falls in front of the doorway. However, with a DH and a beer bribe, that is easily resolved.

My coop early this winter:

We did build a large overhang in the front:

The newest coop is the opposite slope. Not sure why DH designed it this way--maybe because it's so much smaller?

Anyway, the chickens come/go through the floor and then out the sides. There will be two large runs (one on each side, meeting the middle/back of the coop. So yes the snow will pile off the back, but it shouldn't cause any issues as the chickens will have plenty of room to avoid being smushed and the roof is slanted so much that snow really doesn't pile up on it. However if I do have any Darwin-Award-Winning chickens...it's probably better they are not being used in my breeding program!

In relation to the larger coop:

 

[Mac in Wisco]

There are products made for that. I need to do something on one of our barns because the snow and ice have torn the gutters loose. This spring a giant slab of ice and snow came down and fell on a propane tank, crimping the copper line going into the building.

http://www.midwestmanufacturing.com...d=7&lineId=178&productTypeId=46&productId=284

 

[latebloomer]

as an architect i think thermal bridging can be a significant source of heat migration, that may be related to my definition of significant

but the reason i'm going to put insulation on the face of ceiling/roof structure in my metal-roofed coop has two other factors that come to bear as well.

those are, i have sheets of rigid insulation left over from the insulation project i did on my home, and that,

it's easier for me to use a whole sheet than it to cut up the sheet and stick it in the stud bays, i'll just foam the joints with spray foam.

using rigid foam on the face of structure is what we recommend as an office for all projects,

that being said,

we have no chickens for clients at this time...

 

[patandchickens]

Quote:
The thing is, IN REALITY, there is not enough temperature differential for it to MATTER.

The primary purpose of the insulation is to avoid condensation->humidity problems. For this, in reality, it is perfectly fine to have your rafters exposed, they do not get frosty anywhere I've ever lived and even if they did (e.g. wayyy far north) there just isn't much *of* them to cause much problem.

Insulation isn't "bad" as far as retaining warmth in a coop but remember you are going to have ventilation open all winter, I hope, yes, right?, so there is a real limit to how much delta T you're going to get, unless you have a substantial heat SOURCE in the coop (ground heat, thermal mass that gets warmed during the day, etc) and it is also a pretty good-sized coop.

So I mean, sure, if you WANT to insulate the whole ceiling you certainly CAN, but it will not really change the performance of this type of building.

that being said, we have no chickens for clients at this time...

LOL

That is exactly it, though... in some respects, a coop functions under pretty different parameters than a house does, so *some select* things that are no-brainers in a house are either irrelevant or sometimes actively-bad in a coop.

Good luck, have fun,

Pat​

 

[latebloomer]

absolutely going to have ventilation using your tips as rules of thumb

will update you when we have our first chicken clients

really enjoy being part of this community with it's wealth of information.

 

[Cooperkeeper]

"The primary purpose of the insulation is to avoid condensation->humidity problems. For this, in reality, it is perfectly fine to have your rafters exposed, they do not get frosty anywhere I've ever lived and even if they did (e.g. wayyy far north) there just isn't much *of* them to cause much problem."


Pat: We are also using metal roofing and plan to insulate the walls of our new coop SW Michigan) My concern is for the condensation potential. Do you feel with adequate ventilation (vents on every wall and at ridge cap) this will still be a problem or is the insulation going to be required on the interior ceiling area as well?

 

[patandchickens]

Quote:
I strongly expect you'll have a condensation farm if you don't insulate. If you were building an old-style one-wall-open 'fresh air' type coop, then sure, THAT is enough ventilation (if it can be even called ventilation, at that scale

) to avoid condensation problems. But what you describe will probably not do it -- especially since remember you will almost certainly find yourself shutting the upwind walls' vents for much of the winter.

You can insulate now, or you can insulate in Dec/Jan, take your pick

JME, good luck, have fun,

Pat

 

[cooper38]

Condensation occures when you have a temperature differance between the outside and inside of the structure. If the inside temp is close to the outside temp there is no way to get condensation. For example if you put a heater in the coop when it is 40* out and keep the temp inside at 65* you will get condensation. Now this is based on no insulation in the coop. If you insulate just the walls you will still get condensation unless you insulate the ceiling also. A little insulation in the floor is even better if you dont have a enclosed foundation around yor coop. Insulation will help keep snow from freezing and coming off the roof but will not stop it, because the sun plays a big part of the freeze thaw cycle on roofs. The sun warms the metal and thaws the snow that is in contact with the roof and then it freezes back when the sun goes down.

 

[patandchickens]

In many cases you can get condensation with uninsulated walls and not running any electric heater or anything like that. There are LOTS of factors that can lead to the coop wanting to be a bit warmer indoors than out for at least part of the day. For instance simply having a large dirt- or slab-floored coop with less-than-vast amounts of ventilation.

Especially if your coop humidity is somewhat high to begin with due to management practices, it takes very little temperature differential to get condensation->drips/frost->inability to remove humidity via ventilation.

I don't honestly think that in agricultural-type buildings (i.e not heated to household type temps) insulating the ceiling/roof makes one bit of practical difference to snowload/snow-dumps off metal roofs, though. Just from experience and lifetime impressions.

Pat

 

[cooper38]

Yea I worded That wrong, should not have said "now way to get condisation" just that it reduces the chance for condensation.