There is no industry standard and one-size-fits-all ducting for home heating and air conditioning. There are a variety of different materials used, and diameters of ducting vary considerably, depending on the area being cooled or warmed up.
In movies, we’ve all seen the rigid galvanized ducting, usually standard installation in a motel room! This is certainly sturdy stuff, made of 30-gauge galvanized steel. However, it is expensive to buy and fit, and is not flexible, so it is difficult to get it to adapt to awkward room layouts. If you do have this in your home, it will likely only be for your main duct. Metal ducting is usually well insulated, not just to retain heat or cold air, but to also act as a sound insulator. Externally lagging is the best choice as internal lagging is prone to absorbing humidity and accumulating dust.
Flexible ducting is the most popular, especially among DIYers, but don’t be misled by its apparent flexibility. Sure, the ‘slinky’ effect makes it easy to ‘install’, and you can get it in a whole range of diameters, but one common mistake made by those of you who like to do things yourself, flexible ducting still requires attaching to solid structures, rather than being left loose-standing.
Duct board is another option – layers of boarding with insulation included on the inside, though this again can cause a buildup of debris and contaminants on the inside. Note that duct board in not sealed with ‘duct tape’ or duck tape, as it is not suitable for anything other than very temporary measures.
Having the right ducting is important, not only to ensure your home is properly heated in winter, or cooled in summer, but also to ensure your HVAC unit operates at optimum efficiency and therefore at minimum running cost.
Here at A&E in San Antonio, TX we carry out several duct surveys a month, all free of charge, to ensure that our customers are getting the most out of their HVAC system. Why not give us a call and book in your free ducting survey.