The search function is a bit tricky to use so I did a search for you in re: pallet coops in the coop article section:
https://www.backyardchickens.com/se...ild_categories]=1&c[title_only]=1&o=relevance
No matter what you build it from, a chicken coop needs to meet the appropriate criteria to meet chickens' needs:
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.
Where, in general, are you? Climate matters, especially when it comes to housing.
If you put your location into your profile people can give better-targeted advice when you ask questions.