Glazing options for windows, doors and conservatories
When choosing glazing for windows and doors or a conservatory/sunroom, it is very important to understand the various options available and all factors will need to be taken into account from the orientation of the dwelling/extension to the individual characteristics of each site.
You will hear various phrases used within the industry to describe glass types; we have listed below some of these phrases as a guide.
- Low e glass. A low emissivity glass improves thermal performance (keeps heat in).
- Toughened glass. A safety glass that is 5 times stronger than normal glass.
- Warm edge spacer. Reduces heat loss around the perimeter of the glass unit.
- Active glass. A self cleaning glass from Pilkington.
- Low Iron glass. Allows a greater transfer of solar energy into property.
- WERs. Window efficiency ratings e.g. A, B and C rated windows.
- Polycarbonate. A lightweight hollow multiwall sheet.
- Obscure glazing. Used to obscure the view from outside, normally used in bathrooms and toilets.
The three major factors for choosing glass are.
- U value. Measurement of heat transfer through a material (the lower the U value the better the insulation).
- Solar Factor. The percentage of solar energy (heat from the sun) able to radiate through the glazing.
- Light Transmittance. The amount of visible light that is transmitted through the glazing.