Hello Lisa, and welcome to BYC!

Glad you joined.
I have never once brooded chicks in my house. There is absolutely no reason you cannot brood them directly in your coop with the brooder plate. Everybody, and I do mean everybody, will be much happier that way. I cannot fathom the amount of dust and stench 30 chicks would cause inside your house.
It won't be too cold either. I have brooded chicks outdoors with a brooder plate in late April / early May in New York when the temperatures dipped into the low 20s at night and they all thrived. As long as their space is draft free and kept dry they will do very well.
I used one brooder plate with a towel thrown over it for 15 chicks. You with need at least 2 large plates pushed together to cover 30 chicks.
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I would also take the time to make 2 or three of these. They help tremendously with keeping the brooder dry and the chicks water clean. You can have an electrolyte solution in one and fresh in the other. You just raise the bottle one chain link at a time as the chicks grow.
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