I agree with MeepBeep ... The problem with the mesh is it is not coated/protected! It will start to rust soon, painting may slow it down, get a can of rustoleum type spray paint ... Most of the hardware cloth is galvinized coated to protect against rust, and will last much longer.
I would also recommend either (or both) a ridge vent and peak vents ... A ridge vent is a low long cupalo basically a covered opening at the top ridge of the roof, a peak vent is vents that go into the side wall up near the peak of the wall/roof ...
Good ventilation requires not only a side to side air flow like MeepBeep mentioned, but needs a low entry, and high exit ... Warm moist air will rise, and draw in cool fresh air from below ... I did not see any way for air to enter near the floor area ... This could be small or even just cracks in the siding, lots of people want to Tupperware seal up their coops, but then there is no air exchange!
Hardware cloth comes in different size/thickness of wire, not just the spacing ... More common sizes are 19 - 27 gauge https://wireclothman.com/hardware_cloth.html
know what your buying, and what will work best for you!
Also available in 16 gauge!
Know/learn about wire fence sizes (gauge) and what it means, and what it will cost ... http://www.louispage.com/blog/bid/7075/Understanding-Wire-Gauges-Used-In-Welded-Woven-Wire-Mesh-Fence
Know wether your buying galvanized after, or before welding! Which would you prefer?