What is U-factor and SHGC?

What is U-factor and SHGC?

U-factor is the rate at which a window, door, or skylight transmits non-solar heat flow. Solar heat gain coefficient (SHGC) is the fraction of solar radiation admitted through a window, door, or skylight — either transmitted directly and/or absorbed, and subsequently released as heat inside a home.

What is a good SHGC window rating?

When it comes to an optimal SHGC rating, again you will want to look for a rating of 0.25 or less for efficient energy performance and lower A/C costs. Although for people that like their home on the warmer side should choose a SHGC rating between 0.35-0.60 to allow natural solar heat in.

What is the maximum U-factor of glazed fenestration SHGC allowed per code?

The area-weighted average maximum fenestration U-factor permitted using tradeoffs from Section R402. 1.5 or R405 shall be 0.48 in Climate Zones 4 and 5 and 0.40 in Climate Zones 6 through 8 for vertical fenestration, and 0.75 in Climate Zones 4 through 8 for skylights.

Is a .27 U-factor good?

Having a low U-Factor indicates that the window has better insulating properties. U-Factor values generally range from 0.25 to 1.25 and are measured in Btu/h·ft²·°F. Ideally, Florida homeowners should aim to have a U-factor under 0.30 paired with a solar heat gain coefficient (SHGC) under 0.30.

Is lower U value better?

There is a relationship between U-value and R-value—they are mathematical reciprocals of each other. Thus, while lower U-values indicate better insulating performance, higher R-values indicate better thermal resistance.

Is higher U-factor better?

The U-Factor tells you how adequate your windows are at insulation. It’s expressed in Btu/h·ft²·°F and the range is 0.25 to 1.25. The higher your U-Factor rating, the better, as that means your windows are well-insulated.

Is a factor of .30 good?

The “30/30” rule is common: U-factors of under 0.30 (which is good) are often paired with SHGC’s of under 0.30. That’s a good target for the South.

Is U-factor better higher or lower?

The U-Factor measures how well the window in- sulates. While the U-Factor can take any value, in general for windows it ranges from 0.20 to 1.20. The lower the U-Factor, the better the window insulates. The SHGC measures how much of the sun’s heat comes through the window.

Is SHGC same as G value?

The “g” value is also called TSET (Total Solar Energy Transmittance), SHGC (Solar Heat Gain Coefficient) or more simply solar factor. This expresses the share of solar energy that is transmitted through the element to the inside of a building….Solar gain.

Is .30 a good U-factor for Windows?

Is .27 a good U-factor for Windows?

While the U-Factor can take any value, in general for windows it ranges from 0.20 to 1.20. The lower the U-Factor, the better the window insulates. The SHGC measures how much of the sun’s heat comes through the window.