Only laying on a hard surface = broken eggs!!!

[the golden yolk]

Hi guys,
Long story short I inherited some hens when I bought my house a few years ago. I joined up back then to learn a bit and everyone was very helpful, so thank you!
Unfortunately as I live in a suburban Sydney I wasn't expecting foxes in my area and came out one morning to a massacre! We lost them all! The local council and I set traps for a few months and tried to catch the fox but had no luck so after about 10months we got 5 new baby chicks and raised them from scratch... My 4yr old son loved the experience!
This time around I have built them an amazing hutch (it gets locked every night now) that sits within their 5m x 5m open air pen. They get let out to roam the larger yard a few times per week.
Anyway, the chicks are now hens and have finally started to lay. I'm getting about 2 a day with the occasional 3. This has been going on for about 2 weeks now.
The problem is, they seem to only want to lay on a hard surface which is more often than not breaking the shell (the inside skin bit is usually ok so we still keep them). I've made the laying boxes deeper and added more hay daily but they keep kicking it out into the other area of their hutch and laying on the fibro floor! It's doing my head in!
On a couple of occasions I've found the odd egg within the ground of their open air pen and tonight I found that they have been going through a hole in the wall of an adjoining shed and I found 3 eggs layed on the **** concrete floor behind some bags of concrete... Once again cracked on the corner when they lay them!

Any ideas on how to get them to lay on a soft surface??? I'm considering putting down a rubber mat because I'm spending a small fortune on hay (us city slickers getting charged a packet for simple things like hay) lol

Thanks in advance and sorry for the long story!

Cheers!

 

[Ol Grey Mare]

Can you post some pictures (or a very detailed description) of your coop setup and the nest boxes as they all relate to one another. We may be able to see what it is that is putting the birds off using the boxes.

 

[the golden yolk]

 

[the golden yolk]

 

[the golden yolk]

These are some old pics when it was almost finished. The laying area where you can see the chicks standing now has a box in each side with a lip of 60mm high.

As the go up the ramp on the outside heading into the hutch, there's a sliding door. Straight in front of the door is an open section, turn right and there is 2 suspended timbers for them to sleep on (about 10cm about the floor). The open area and the sleeping area floor is actually like a big drawer so I can slide it out and clean it out when needed.
At the other end (if they turn left when going into the hutch) is the. 2 laying boxes.
Like I said they lay there most of the time but they kick out all the hay into the open area inside the hutch and lay on the hard fibro floor.