High end shed: sealed envelope or open to roof?
Building a 12×15 multipurpose shed, most of the time just storing stuff unattended in Central Texas heat (and very rare freeze). Framed brick construction (light colored brick) with white metal roof, one window and french doors. Roof on top of radiant barrier. Attempting to beat the heat (9 mo/year and sometimes beyond 110 degrees), and condensation after fast temperature drops (sometimes >10 degrees/hour). No use of grid power (eventual plan is small solar system for lighting, fan, and radio). 3 months of the year there can be cold weather also, occasionally freezing.
Should a shed like this optimally be wide open and unfinished inside from side vents to ridge vent? That’s typical commercial shed design. Or optimally should roof system be self-venting and sealed from rest of shed with soffit vents providing airflow around roofing system radiant barrier? In former case, I’m not sure if it’s even useful to finish interior walls inside structural wall and framing. In latter case, all finished walls and ceiling could give sealed envelope if I go that way; I’m thinking that would necessitate upper and lower side vents with dampers, optimally motorized and humidistat controlled, to prevent condensation internally when there are large temperature swings. It seems to me like that sealed envelope would be the best approach, but not sure if it actually accomplishes much since frequent or continuous venting is still required anyway. I’ve never seen anyone else go sealed interior envelope in shed situation. Won’t energy flows (including convection through venting) eventually bring interior to outside temperature, then perhaps best that can be done is prevent exceeding outside temperature and humidity with continuous ventilation?
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