Vinyl Window R Value

Standard clear glass has an emissivity of about 0 84.

Vinyl window r value. The r value as it is known to most consumers is really an inverse representation of the u value. Energy and the environment. The higher the r value the greater the resistance. The more common term r value refers to the resistance of the window to heat conduction and it is the inverse of the u factor that is r value 1 u factor.

When determining how much insulation you need don t guesstimate calculate. The rate at which the glass transfers loses heat. If you like math a u value 1 r value the u value is the inverse of the r value. A double pane window with a low e coating will have an r value equivalent to or better than a triple pane window.

While the u factor is used to express the insulation value of windows r value is used for insulation in most other parts of the building envelope walls floors roofs. The r value is the measure of heat flow resistance the higher the r value the better. A window is considered to be low e if its emissivity is 0 35 to 0 05. Our windows and doors are engineered for energy efficiency.

To compare r value and u factor. John wiley sons inc 2006. U value is the amount of heat transferred through a material. Concrete homes magazine web search 5 18 2010 r value for concrete glass other materials wikipedia web search 5 18 2010 citing ristinen robert a and jack j.

Know exactly how much you need with our project calculators. The lower a unit s u value number the slower it transfers heat. R values of uninsulated concrete. While they are related different assumptions and test criteria are used in calculating the two values so they cannot be directly converted.

Fortunately window technology has greatly improved so it is now possible to have large expanses of windows. We ve designed the entire window including the frame and sash to perform at its best. As a window s emissivity decreases its r value increases. R value measures how well certain building insulation materials can resist heat.

The higher the r value the greater the insulation performance. Alside vinyl windows have several replacement and new construction lines including double hung casement and bay windows. Optional foam insulation can further increase energy performance. Better windows have high r values and low u factors see table 1.

The lower the u value the slower the rate of heat flow and the better the insulating quality. Alside windows are custom made to fit existing window openings. How can a replacement window s u value be improved. Since the different parts of a window all have different u factors.

And we test them to the extremes so you can count on them to last.