Metal Roof Thermal Expansion

It is important to note ambient air temperature will differ from the temperature of the metal and direct solar radia tion plays a major role in this process.

Metal roof thermal expansion.

Thermal expansion contraction is responsible for most roof leaks. Expansion and contraction factors often are overlooked or regarded as insignifi cant in metal roof system design and construction. The rate of thermal movement varies by the type of metal installed and temperature of the base metal. You can demonstrate this to yourself quite easily by trying to carry something large and flat on a windy day.

The sun hits your roof and heats it up. As the lumber expands it moves and it will rub against other pieces of wood that aren t moving at the same rate. The wind pressure against a roof or an entire home can be enormous. Years ago as a young builder i almost got blown off a roof while trying to carry a sheet of 4 by 8 plywood.

For example expansion and contrac tion can cause metal components to. The term thermal movement refers to a material s dimensional changes resulting from temperature swings. It s thermal expansion and contraction. A material experiencing a rise or decrease of temperature expands or contracts respectively this poses an interesting challenge when it comes to designing metal panel roof assemblies.

Metal roof thermal expansion. Also the surface temperature of metal roofing materials can range from 25 degrees. The following table provides the coefficients of linear thermal expansion and representative thermal expansion values for various building materials where possible the values were taken directly from manufacturer technical data sheets and reflect the coefficients of linear thermal expansion for specific representative products. Metal roof systems can be the least forgiving of all roof sys tems if provisions for expansion and contraction are neglected.

In the long run a properly designed weather tight roof will cost less than an improperly designed leaky low cost roof. Get free shipping on qualified metal roofing or buy online pick up in store today in the building materials department.