I built a 10x8x6' shed for my Aldabran tortoises. The YF tortoises live right next door. So I sectioned off 4' inside the shed for them. Then, to give the shed more shade (it gets pretty hot here in the summer) I build an additional roof over it and put up lattice on the sides of it. I didn't want to cut the lattice so I just extended it off the back side of the shed and made the YF tortoises a 'porch' off of their section. During the winter I wrap the porch with plastic film. If the sun shines even just a tiny bit, it heats up inside the porch and I'm able to allow the YF tortoises out into that area. So they're not locked inside the shed all winter. In the porch picture you can see the little tortoise door leading out to the rain forest, but it's blocked by a plank right now.
(There's a volunteer fig tree growing on the porch)
(There's a volunteer fig tree growing on the porch)