How many hens will fit?

[MIchickenlady]

I bought a used shed to convert to a coop like the one pictured recently, 10 x 16 with a porch.
I plan to build a screened off 3 ft x 10 entrance area for storage & supplies, that will leave me with 10 x 12ish floor space for hens.
The ceiling is high, 8 ft, and two rotating runs will be 24 x 24 one run off each side, with some limited free ranging.
How many standard hens should I plan on total? I have 4 standard hens who are going on 4 yrs old.
If I get 14-16 this year, could I safely plan to add another 5-6 hens the following two years to keep egg supply steady? I need them to be able to keep warm in the winter, so should I get more this year so there will be enough of them to stay warm next winter? I am thinking about 30 birds total-does that sound reasonable?
Open to any and all suggestions- thanks!!

 

[rosemarythyme]

So a few factors:
1) More birds does not equal more warmth. Don't stuff a coop with birds thinking that'll keep them warmer. All it does is increase the ventilation you'll need, and you will need to be adding some vents as things currently stand.
2) Are the runs going to be covered and weatherproofed so they can be used even during winter storms? If yes, the coop can hold about 30 standard hens. If no, count on closer to 15 hens, as you need to account for them not going out in the worst of weather and cabin fever is a thing with chickens too.

 

[Alagirl]

I believe the suggestion is 4 square feet per hen floor space, one foot roost space.
10 square feet in the run (disclaimer: I am just repeating what the veterans on the forum are saying)
Edit to take latenight idiot math out.

 

[MIchickenlady]

So a few factors:
1) More birds does not equal more warmth. Don't stuff a coop with birds thinking that'll keep them warmer. All it does is increase the ventilation you'll need, and you will need to be adding some vents as things currently stand.
2) Are the runs going to be covered and weatherproofed so they can be used even during winter storms? If yes, the coop can hold about 30 standard hens. If no, count on closer to 15 hens, as you need to account for them not going out in the worst of weather and cabin fever is a thing with chickens too.

Yes, adding vents up high for sure. There are two operational 16x24 windows I will cover with hardware cloth on the outside. Metal roof covered runs that will be tarped for winter use. Thanks for your thoughts, much appreciated!

 

[DobieLover]

Yes, adding vents up high for sure. There are two operational 16x24 windows I will cover with hardware cloth on the outside. Metal roof covered runs that will be tarped for winter use. Thanks for your thoughts, much appreciated!

You'll need better placed ventilation than the windows. You need to position ventilation to promote air flow inside the coop without having the air blow across roosted birds. Adding a soffit vents with paired ridge and/or gable vents will fit that bill.
Additionally, if the run is as predator proof as the coop you can leave the pop door open year round to promote fresh air intake through the lower opening.

 

[3KillerBs]

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.

For 20 hens, this year's 16 plus your current 4:

• 80 square feet in the coop. 8'x10' is the most practical because 7'x12' or 6'x14' require a lot of weird cuts.
• 20 feet of roost
• 200 square feet in the run. 10'x20', 12'x16' or 8'x25' as suits the land available.
• 20 square feet of ventilation.
• 5 nest boxes.

I am thinking about 30 birds total

10x12 with 30 birds would be just exactly 4 square feet per bird.

First, however,

The square feet per bird breaks down a bit for very large flocks in very large facilities -- because each individual bird has more space to evade and avoid any other individual bird.

Second,
These numbers are guidelines, not hard and fast rules. This article is invaluable for understanding the many factors that go into determining chickens' space needs: https://www.backyardchickens.com/articles/how-much-room-do-chickens-need.66180/

30 birds will need 30 square feet of ventilation -- potentially more depending on exactly how it's sited. But it will have to be carefully placed to prevent drafts since you're in a severe winter area. That 8-foot ceiling is a great advantage for this.

Here's my article on ventilation: https://www.backyardchickens.com/articles/repecka-illustrates-coop-ventilation.77659/

And here are some excellent shed-conversion coops to help inspire you:

https://www.backyardchickens.com/articles/the-mulligan.74743/
https://www.backyardchickens.com/articles/aarts-coop-page.65912/
https://www.backyardchickens.com/articles/the-scoop-on-a-rubbermaid-big-max-coop.76444/
https://www.backyardchickens.com/articles/toy-shed-conversion.64879/

 

[aart]

Adding a soffit vents with paired ridge and/or gable vents will fit that bill.

Yes!
But first they will have to extend the roof to form said soffits.

 

[Auntiejessi3]

I agree with the above posters in regard to ventilation....how many eggs are you needing/wanting? Are your 4 older hens still laying? Why don't you add 4-6, then next spring another 3 and so on instead of filling your coop all at once?

 

[MIchickenlady]

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.

For 20 hens, this year's 16 plus your current 4:

• 80 square feet in the coop. 8'x10' is the most practical because 7'x12' or 6'x14' require a lot of weird cuts.
• 20 feet of roost
• 200 square feet in the run. 10'x20', 12'x16' or 8'x25' as suits the land available.
• 20 square feet of ventilation.
• 5 nest boxes.

10x12 with 30 birds would be just exactly 4 square feet per bird.

First, however,

The square feet per bird breaks down a bit for very large flocks in very large facilities -- because each individual bird has more space to evade and avoid any other individual bird.

Second,
These numbers are guidelines, not hard and fast rules. This article is invaluable for understanding the many factors that go into determining chickens' space needs: https://www.backyardchickens.com/articles/how-much-room-do-chickens-need.66180/

30 birds will need 30 square feet of ventilation -- potentially more depending on exactly how it's sited. But it will have to be carefully placed to prevent drafts since you're in a severe winter area. That 8-foot ceiling is a great advantage for this.

Here's my article on ventilation: https://www.backyardchickens.com/articles/repecka-illustrates-coop-ventilation.77659/

And here are some excellent shed-conversion coops to help inspire you:

https://www.backyardchickens.com/articles/the-mulligan.74743/
https://www.backyardchickens.com/articles/aarts-coop-page.65912/
https://www.backyardchickens.com/articles/the-scoop-on-a-rubbermaid-big-max-coop.76444/
https://www.backyardchickens.com/articles/toy-shed-conversion.64879/

Thank you thank you thank you so much!!!!