Coops & runs

Chicken coop size guide (UK): how big should your coop be?

Ignore the sticker that says “fits 6 hens”. Size your coop so hens sleep comfortably — and so you can clean it without hating your life.

Brutal truth: if the coop is awkward to clean, you will procrastinate — and that’s when smell, mites, and stress creep in.

Perch space Nest boxes Ventilation Realistic capacity

The short version

Perch space matters more than floor space: hens sleep on perches.
Ignore “capacity” labels: many are best‑case, summer‑holiday numbers.
Nest boxes don’t need to match hens: they share (1 box per 3–4 hens is common).
Ventilation beats “warmth”: damp + ammonia is what causes trouble.

Coop size is about comfortable roosting and hygienic mornings.

Run size is what prevents bullying, mud, parasites, and boredom.

Priority order: run space → security → ventilation → easy cleaning → everything else.

Use the calculator for run sizing.

If you’re seeing these, jump to ventilation and cleaning.

At night, every hen wants a stable perch position. If they can’t, they jostle, fall, and sleep where they shouldn’t.

Rule of thumb: aim for roughly 20–25cm of perch length per standard hen (more for large/heavy breeds).

Perches should be higher than nest boxes so hens don’t sleep (and poo) in the boxes.
Use wide, rounded‑edge perches (comfort + foot health).
Leave enough space between perches so birds don’t poop directly onto each other.

If your coop is “tight”, you can sometimes improve it just by adding a better perch layout — but don’t force a tiny coop to do a big‑flock job.

A surprising reality: hens often want the same box, at the same time. More boxes can help, but it’s not the main limiter.

Rule of thumb: 1 nest box per 3–4 hens is a practical starting point.

Dirty eggs are usually a run/mud + hygiene problem, not “wrong nest boxes”. See mud control.

Coops are often “rated” for the absolute maximum birds you could squeeze in — not for year‑round comfort.

What you see	What it often means	What to do instead
“Fits 6 hens”	Small hens, perfect weather, no one grumpy	Size for your actual breeds and assume winter confinement happens
Cute miniature coop	Difficult access, fiddly corners, damp build‑up	Choose the coop you can open fully and clean fast
Thin run attached	More like a “holding pen” than a run	Plan a proper run: see run sizing + build guides

Brutal truth: many keepers buy twice — once for the “starter coop”, then again for the coop they should’ve bought first.

A coop can be “big enough” and still be unhealthy if it traps moisture.

A “4 hen coop” might be fine for smaller hybrids… and miserable for heavy birds like Brahmas or Orpingtons.

Reality check: if your hens look “compressed” on the perch, your coop rating is lying to you.

Use the Breed Finder to identify heavier breeds, then size up.

And don’t forget the run: run sizing guide.

The best coop is the one you’ll actually maintain.

Design features that save you

Problems that vanish when you clean properly