The Sheet Metal and Air Conditioning Contractors’ National Association (SMACNA) has published the fourth edition of its HVAC Duct Systems Inspection Guide.

Sheet metal fabrication is a versatile manufacturing process used to produce most components and products from thin metal ...

These tradespeople may specialize in heating, ventilation and air-conditioning systems (also known as HVAC), or architectural, industrial and service sheet metal work. HVAC workers fabricate and ...