Because asbestos can be woven to reinforce, insulate, and fire-proof other materials it was used widely in construction materials such as insulation, patching and spackling compounds, joint compounds, gypsum wallboard, paints, floor tiles, ceiling panels, roofing shingles and many other products. Most homes and buildings built before the mid 1970’s contain some asbestos products. Carpenters, bricklayers, painters, plasterers, roofers and masons were often exposed to asbestos during this era. Even today, people working in the building trades who perform repairs and renovations may be exposed to asbestos from older structures, which may lead to cancer.