Coops size and ventilation needs

[mowin]

That is why I’m here to make sure it is adequate, haha any tips on the roost bar placement below vents?

Ventilation should be well above the birds heads while they are on the roost to avoid drafts. Your going to be limited with your coop not being very tall. Roosts should be higher than the nest boxes to avoid them sleeping in them.

 

[rosemarythyme]

They will still have the full 30x16 run but only the 8x4 will be covered to protect from elements on real harsh weather days, otherwise they will have full access to the entire run if they choose to. I figured I was squeezing too many in but thought I should ask first, thank you! Does the run set up make more sense now? It’ll be like 3.5 walls and a roof to help prevent harsh weather but still allow access to more run and ventilation in covered area

Makes sense, but knowing that many chickens will choose not to go out in very windy/snowy conditions, they'll likely stay in only that 8x4 area, so effectively that is the only outside space they'll have to use in the winter.

Now if you realistically can keep some of the non weatherproofed run area shoveled and maybe put out some straw bales for wind buffers, then there's a higher likelihood that they'll use the larger run space, which would give you a little more wiggleroom as far as number of birds.

 

[aart]

only the 8x4 will be covered to protect from elements on real harsh weather days

I also have only an 4x8 protected area in my run it stay dry all year, except when the snow blows in from a certain direction. I do shovel out part of the run and they will walk on the snow if it's not too deep, this also helps clear the run faster once snow melt season comes around.
BUT....I also have a large coop for those days when they can't go out at all.

 

[3KillerBs]

Welcome to BYC.

That coop is going to be VERY tight, especially since you're in a severe winter area where they will not have the use of the entire run for long periods of time.

The Usual Guidelines

For each adult, standard-sized hen you need:

• 4 square feet in the coop (.37 square meters)
• 10 square feet in the run (.93 square meters),
• 1 linear foot of roost (.3 meters),
• 1/4 of a nest box,
• And 1 square foot (.09 square meters) of permanent, 24/7/365 ventilation, preferably located over the birds' heads when they're sitting on the roost.

6 hens

• 24 square feet in the coop. 4'x6' is the only really practical build for this given the common dimensions of lumber. If you can't walk into it, put the access door in the middle of the long side to make sure you can reach all areas of the coop because a stubborn chicken WILL press itself into/lay an egg in the back corner where you can't reach.
• 6 feet of roost
• 60 square feet in the run. 6'x10' or 8'x8'.
• 6 square feet of ventilation.
• 2 nest boxes, to give the hens a choice

8 hens

• 32 square feet in the coop. 4'x8' is approaching the limits for a non-walk-in coop even with the access door in the middle. 6'x6' should be walk-in because even the tallest chicken-keeper won't be able to reach the far wall.
• 8 feet of roost
• 80 square feet in the run. 8'x10' is a nice looking number but, remembering the common dimensions of lumber, a roomier 8'x12' is actually easier to build. 6'x14' looks good on paper but would require a lot of weird cuts.
• 8 square feet of ventilation.
• 2-3 nest boxes.

In order to give you an illustration of what actual birds look like in the space, here is a photo of three young cockerels, who are just about the size of adult hens of their breed, in a 4x8 space:

Here are some useful articles for you:

Article 'Cold Weather Poultry Housing and Care'

Repecka Illustrates Coop Ventilation