How many MHPs for 100 chicks in outdoor brooder?

[eleanors_garden]

I’m excited to announce that I’ll be bringing home 100 chicks to add to my little flock in June!
(if you've just come from my other anxiety riddled post, welcome to another lmao)

After doing extensive reading I’ve decided to outdoor brood. Originally we built a wild wall to separate the coop with the rest of the barn so we can extend the coop as needed- which now we can shift to the next stall to create the brooder coop. Between the coops will be 1/2in wire hardware cloth for the flocks to experience each other safely.
There’s an ext access door in the brooder coop which will lead to a separate run side by side the original- with access being granted at 6 weeks.

My main questions...
1. How many heat plates/caves/MHPs should I set up for 100 chicks? What is the standard sqft per chick/ per plate?
2. Will I have to add more MHPs weekly to accommodate rapid chick growth / prevent overcrowding?

Previously I used heat lamps for the brooder but I didn’t love it for various reasons. It could be argued that some reasons for my distaste are due to skill issue in not finding the “sweet spot,” but it felt inadequate. Which is why this time I’d like to try MHP. It simulates a more natural environment. And that's what I'm going for this time round with combining these methods.

I was looking at the Sunbeam 20x24 heating pad. But even with these dimensions, and the rate chicks grow, setting 5 caves with 20chicks per leads to eventual overcrowding.... I read one thread that suggested 3 for 75 chicks, but I can't remember the dimensions of their MHPs. And I also can’t find any rough math on chicks per plate, only per brooder/coop. The only thing remotely close is that plates advertise higher- so if it’s rated 15chicks per plate it actually means 7-8.

Would it be wiser to stick to the heat lamps in this case since there will be a large quantity of chicks?
On the flip side it seems more fitting to have MHP since they will be more “exposed” to the elements.

Anyways… I appreciate any and all input. Such a wonderful, and knowledgable community to be part of! And thank you in advance for the guidance.

 

[Kiki]

Based on the ages of the chicks mentioned in your other post from today I would say ZERO heating pads. They should just fine with no added heat at this age.

 

[rosemarythyme]

Other thread you said 50 are 4-5 weeks? Those shouldn't need heat unless you live somewhere unusually cold.

For the younger group you might need some heat but we'd need to know your projected temperature ranges. For large groups I'd advocate for a heat lamp or two vs MHPs, which really aren't efficient for larger groups.