100 Building Plastics Facts

Building plastics are everywhere in modern homes — rooflines, gutters, cladding, trims, and window frames — but very few people know much about how they perform or why details like expansion gaps matter.

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This page isn’t manufacturer jargon. It’s a collection of 100 practical facts — part trade guide, part myth-buster — pulled together from real jobs, installer know-how, and manufacturer specs.