How do I explain ventilation to my contractor?

[Folly's place]

That's good, and have the biggest openings on the south and east sides. You could add a window in the door too.
In winter, doubled plastic sheeting can go over some of the lower windows, but upper ventilation must be present.
It needs to be light in there, not dark.
Is the floor treated plywood? Add protection of some sort, either a sheet of vinyl flooring, or some good coating, to delay the rot.
Mary

 

[OhZark Biddies]

The coop will be in a fully enclosed run and surrounded by electric fence.

I think the 3/8" gap is fine. I might add a few holes in the gable but it's likely not that big of a deal either way.

The "window vents" aren't bad as far as I'm concerned, they give you the opportunity to open them in hot weather, leave them slightly ajar in cooler weather and close them in frigid weather.

The fold down window was likely thought to be for functionality: easy to tip down, but as someone else mentioned, I'd put the hinges at the top, and use a something simple to prop it open, or rig a bit of twine from the eave to hold it open... otherwise inevitably a chicken will jump up there and get herself wedged in and stuck, and/or they will fly up and sit on it and spring the hinges, etc.

Other than that I don't see much I'd change, maybe some scrap vinyl flooring on floor?

Congrats, looks like a fine coop to me.

 

[JDN]

I'd face it south/southeast and shut the glass window in the rain and nothing else.

Chickens will be fine, plenty of ventilation...If it makes you feel better, secure the hardware cloth with screw/washers, or fence staples.

In fact, if you look at a woods coop, the ventilation in winter mode is all down low.

The drafts to be most concerned with will come from the North, Northwest, Northeast.

Anything that comes from the South/Southeast will bring warm air, which won't bother your chickens.

Remember, Mr. Woods originally tried to house his chickens in trees, only abandoning that since people would steal them.

 

[aart]

So the 3/8" gap under the soffits on both sides isn't considered ventilation at all?

@aart What do you mean by "top plate"? What size hole would you recommend for the gable vents?

Yes, it is... and it is good ventilation in winter for people who live where it's get really cold and snows and you want all the windows closed.
The top plate is the horizontal 2x4 at the top of the wall.
I might cut the little bit of siding sticking up above the top plate to enlarge the opening for soffit ventilation...it's not a lot of extra but every little bit counts...it would be a tricky cut tho. I assume that it's open to the exterior so you'd want HC up there on the outside to keep anything from crawling in, a pic of under the soffit would tell the tale.

Measure the space you have and get the biggest you can fit.

This^^^
Something like this would be perfect...it would let air in and out and keep snow from blowing in, might be hard to find the right size, will take some searching once you know the measurements.

 

[aart]

In fact, if you look at a woods coop, the ventilation in winter mode is all down low.

The Woods design is special and building is of specific proportions, it shouldn't be used as a ventilation example for any other type of structure.
Woods has one wall completely open(not down that low) and all other openings are closed tight in winter...this forms an air cushion so air cannot move thru the building.

 

[Shamo Hybrid]

If you're not completely satisfied with it, he should make it right! Don't modify it and cut into it if you're not comfortable..... you paid him to do the work, he should make sure everything is done the way you want it.

 

[aart]

If you're not completely satisfied with it, he should make it right! Don't modify it and cut into it if you're not comfortable..... you paid him to do the work, he should make sure everything is done the way you want it.

It's not really that simple.

 

[Shamo Hybrid]

It's not really that simple.

How is it not? It's like when you take a car in to get a paint job done or to get re-carpeted, if it's not to your liking....... you point it out to them and they have to make it right for you, the paying customer! This is why it's wiser to pay only half the money for the contractor to do the job, and then pay him the other half once everything is complete and you are satisfied with the work!

 

[lazy gardener]

Aart and Mary have pretty much nailed it. As far as having the contractor make modifications, he should not be held liable for any thing that he did subject to his interpretation of "word of mouth" instruction. A lot can get lost in the translation. I would exchange those plywood flaps over window openings for "see through windows" of some sort. But, that can be done down the road. Louvered venting is a must for providing ventilation while keeping wet stuff out. It also allows air exchange while minimizing drafts. I would exchange those barrel locks for hasps which you can slide a carabiner through. For finishing the inside of the coop, I would paint all surfaces, and use Black Jack on the floor and up the walls at least 12".

 

[lazy gardener]

If all details were not specified prior to construction, with a written contract and specific detailed blueprints, and material specifications, then, it becomes an issue of what the customer envisions in his head not matching what the contractor is hearing or interpreting based on the customers vague descriptions. I'm not saying that the customer in this case was being vague. But, without a detailed blueprint, things get lost in the interpretation. I grew up with a dad who was a contractor, and my husband has spent YEARS involved in design work for construction. Often, the customer will ask for something that would result in a building not meeting codes, or not being structurally sound. A blueprint with appropriate cross sections for the customer to view and approve before materials were even purchased would have prevented any miscommunication.