U Factor And Shgc Standard French Doors

U factor is the rate at which a window door or skylight conducts non solar heat flow.

U factor and shgc standard french doors.

South facing glazed doors in cold climates should have a high shgc. Doors are a little different. U factor shgc solar heat gain coefficient product type any awning casement double hung fixed casement french door horizontal slider picture window side lite transom single hung sliding glass door storefront door storefront window. Solar heat gain and u factor.

In the southern zone skylights must have a u factor of 0 60 or less and an shgc of 0 28 or less. For windows skylights and glass doors a u factor may refer to just the glass or glazing alone. Each rating is split into two values. It s usually expressed in units of btu hr ft2 of.

Nfrc u factor ratings however represent the entire window performance including frame and spacer material. This tool gives you the flexibility to select the required energy star zone u factor shgc or vt and determine which milgard window and door products meet the selected requirements. Solar heat gain coefficient measures how well a product can resist unwanted direct or indirect solar radiation. The milgard energy calculator provides a quick and easy way to help you select windows and doors that can meet local energy codes and project requirements.

Energy performance data for select combinations of options is available in table format on each product page. Glazed doors in hot or temperate climates should have a low shgc. This tool provides some of the most common options on windows and doors and related nfrc certified values. Solar heat gain coefficient shgc a measure of how well a glazed door assembly absorbs or reflects heat from the sun.

To access those tables select the individual product of interest and scroll down to the professional resources section. The u factor of skylights in climate zones 4 to 8 is not to exceed 0 75. In the south central zone skylights must have a u factor of 0 53 or less and an shgc of 0 28 or less. Doors must now have a much lower u value also known as u factor see below and solar heat gain coefficient before they can earn the energy star label.

In southern climate zones 1 to 3 southern tennessee to the tip of florida there is no u factor cap but the shgc is not to exceed 0 50. This radiation can cause your home to heat regardless of outside temperature which. To be labeled as an energy star qualified product the nfrc ratings u factor and shgc or solar heat gain coefficient ratings must meet the 2015 energy star eligibility criteria for. The same shgc cap of 0 50 that applies to vertical fenestration in climate zones 1 to 3 also applies to skylights.