Good morning ...
Here are the pictures of the chook house I build last summer:
You can fit about 7-8 as they just go there to lay and roost ...
There is a nest box accessible for the side .. so no need to get inside to collect your eggs, one nestbox of 30cm x 30cm is enough for 2-3 laying hens .. and they don't lay at the same time. ...
There is a big service door on the other side for easy cleaning and access ...
The "roosting bars" have to be at about 50cm high ... and place far appart .. to make sure that they can't reach each other while roosting .. that would avoid picking as they wouldn't feel confined .. and make sure that all the roosting bars are at the same height .. otherwise they will "fight" for the highest spot .. the inside of the house should be at least 1m high for them to jump easily up and down ...
A good idea is to have the inside floor like a box, by that I mean elevated sides to make it like a litter tray ... in fact it is .. because like that it can accumulate a good bit of wood clipping & saw dust, or straw .. and it prevents them from scratching it out ..
pickup the poos every couple of days ... thrown in an extra little bit of clippings or straw .. that will save you from cleaning the whole house every week .. but that all depends on the number of hens you keep ..
Try to allow some air circulation vent for the nice days .. that you can close for the winter when it gets too cold ...
But make sure these vents don't create a draft .. as they don't like that ...
The house should be elevated from the ground .. to avoid dampness and all ...
I based mine on several plans .. but that's the one I found the most useful .. just scale it and modified it as you wish ..
http://www.buildeazy.com/chicken_coop_metric_1.html
As for the run .. I have 3 cats and loads of "ferral cats" (wild at least, but even smaller than our domestic ones, with short legs) .. and we never had a single problem with that .. even though they are all pretty good hunter ... they don't bother with the hens .. too big for them .. and my hens are just running loose everywhere .. ie proper free range .. so no need for a pen, just a strong hen house ... and lock them up inside at night .. they'll go back on their own .. so no hassle ..
Or you can just make a fence about 1,5m high with chicken mesh, and dig down about 30cm of the chicken mesh to prevent foxes and other animals to crawl underneath. And if the hens flies over and you can simply clip the feathers of one wing .. that will make them go in circle when trying to fly .. .
And if you have chicks, you can make a broody cage ...
Good luck .. and send us pics when yours is done ..
Camile