Leghorn hens laying eggs

[Cavendish Chickens]

Okay, my girls are only 3 1/2 months old. They hatched around June 12th. I've heard that hens start laying anytime between 4-6 months of age. We don't have a nest box yet, and I was wondering should we rush to get one built and set up, or can we take our time? I won't have the money until around the 15th to buy wood and supplies to build the nest box. This is why I am asking. The side we are putting it on is 4 ft wide by 4 ft tall, and the front where they come out is 8 ft long. We have large, thick tree branches inside for roosts, and they sit at an angle. The girls love them. They sleep on them at night, while the roo sleeps on the floor. He's about 4 1/2 months old (hatched May 21st). Would he ever lay in the nesting box with the girls? So I guess, wrapped up, all of my questions are:

1) When do leghorn hens usually start laying?
2) Can we wait a little longer to build a nest box, or should we hurry and do it now?
3) Would the rooster ever lay with the girls in the nest box?

Thanks everyone!

 

[chics in the sun]

I only have one, and she didn't lay until about 21 weeks, so I'd say you have plenty of time if they are only 14 weeks now.
I'm not sure what you mean by the rooster laying in the nesting box with them. I'm not allowed roosters, so someone with more experience will have to answer that, but I don't think one would. That would probably just annoy a hen that is working hard at laying an egg. They don't like to be bothered, although other people have talked about their roosters pacing around the nest boxes while a hen is laying.