U Factor Windows And Doors

The lower the u factor the better the resistance to heat flow in and out of the window.

U factor windows and doors.

U factor is the rate at which a window door or skylight conducts non solar heat flow. Improved education and awareness of the cost of heating and cooling that escapes from poorly insulated components and glass panes have led to window and door manufacturers developing energy efficient windows and doors typically labeled r5 u 2 meaning the glass is the most energy efficient possible at a 5 rating and the window or door with all. It s a particularly important measure for climates with colder winters. Lower numbers indicate greater insulating capabilities.

Epa requires that the u factor for energy star labeled products is certified and listed on the product label. Triple glazed windows may have a u factor as low as 0 15. U factor values generally range from 0 25 to 1 25 and are measured in btu h ft f. It s a measure of total heat flow through a window or door from room air to outside air.

Double paned windows may have a u factor at or below 0 30. Gases are heavier than air and therefore provide insulation resistance to air. Low u factors are most important in heating dominated climates although they are also beneficial. How to determine u factor for windows.

High performance double pane windows can have u factors of 0 30 or lower while some triple pane windows can achieve u factors as low as 0 15. The range is from 0 to 1. For windows skylights and glass doors a u factor may refer to just the glass or glazing alone. This means you get a better quality window.

The optimal measure for your window will depend on your location. What is the best r value for windows and doors. At u factor window door we utilize the most trusted windows doors and skylights on the market. Look for a low u factor.

We pride ourselves on quality craftsmanship reliability and our excellent reputation. It s usually expressed in units of btu hr ft2 of. The nfrc is a non profit group that administers a uniform independent rating and labeling system for the energy efficiency of building components including windows doors skylights and attachment products. The label shows the solar heat gain coefficient shgc and u factor for the door.

U factor measures the rate of heat transfer and tells you how well the window insulates. A u factor rating generally refers to the entire window. Nfrc u factor ratings however represent the entire window performance including frame and spacer material. Simply put u factor measures how well a window keeps heat inside your home.

Shgc measures how well a product keeps out solar heat. The lower the u factor the better the window insulates. The u factor rating system was devised by the national fenestration rating council nfrc. The range is from 0 00 2 00.

Look for a low shgc in a climate that mainly requires cooling and a high shgc in a climate that requires heating. The values for u factor range between 0 25 and 1 25.