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Hi everyone! As a science enthusiast, I've been fascinated by how climate affects building materials. In my research, I've found that plaster cracking in **dry climates** (like the Southwest) often occurs due to **rapid moisture loss** during curing and **thermal expansion/contraction** from temperature swings. The low humidity causes plaster to dry too quickly, creating shrinkage cracks. In **humid climates** (like the Southeast), cracking is more often related to **moisture absorption** from the air, which can cause swelling and eventual cracking as it dries unevenly. Has anyone observed these patterns in their homes?

Great topic! As a nature photographer who travels between both regions, I've noticed this in old buildings I shoot. In Arizona, I see **fine, web-like cracks** in plaster that seem to follow the sun exposure patterns - worse on south-facing walls. In Georgia, the cracks tend to be **wider and more localized**, often near windows or doors where moisture might enter. The humidity there seems to make plaster more 'spongy' before it cracks. Anyone else see this connection with building orientation?

Interesting observations! Working night shifts, I've had plenty of time to notice my home's plaster in different conditions. Here in Florida (humid Southeast), I get **seasonal cracking** - worse in summer when the AC runs constantly, creating huge humidity differentials between inside and outside. My cousin in Nevada says his cracks appear more in winter when indoor heating dries everything out. Maybe it's not just the climate, but **how we climate-control our homes** that matters?

Excellent point, Jack! You're touching on **hygrothermal stress** - the combined effect of temperature AND moisture changes. The AC example is perfect: rapid cooling causes condensation, then drying, creating stress cycles. In dry climates, heating systems reduce relative humidity even further. This is why proper **vapor barriers** and **humidity control** are crucial in both regions, though the solutions differ. Dry climates might need humidifiers, while humid climates need dehumidifiers and better ventilation.

That explains why I see more **repair attempts** on Southeast buildings - often with mismatched materials that crack again quickly. In the Southwest, I notice people tend to leave the cracks alone or use flexible fillers. From a photography perspective, these cracks tell a **climate story** - the dry climate cracks look like desert canyon networks, while humid climate cracks resemble river deltas! Maybe building materials should be region-specific from the start?

As someone who's patched plenty of cracks during my off-hours, I can confirm the repair differences. In humid areas, you **must address moisture sources first** or the crack returns in weeks. In dry climates (from what my Southwest friends say), it's more about **allowing for movement** with elastic compounds. Maybe we need a 'plaster climate zone' guide for homeowners? I'd definitely use it during my late-night home maintenance sessions!