Pilkington Optitherm™ S1 Plus is the latest in our low-e range offering ultra low-emissivity and achieving a Ug-value of only 1.0 W/m 2 K when incorporated in a double glazed IGU.

Pilkington Optitherm™ S1 Plus is an off-line coated, single stock product, offering superior thermal insulation performance with Ug-value of 1.0. Our own range of energy-efficient double glazed units for use in domestic applications.

When fitted with Pilkington Activ™ combined with a thermally efficient glass such as Pilkington Optitherm™ S1 Plus, your transformed conservatory will be warmer in the winter, cooler in the summer and will look cleaner than ordinary glass.

An insulating glass unit comprising 4 mm Pilkington Optifloat™ Clear outer pane, 16 mm argon gas-filled cavity and 4 mm Pilkington Optitherm™ S1 Plus inner pane has a centre pane U value of 1.0 W/m 2 K. For more information on our range of products for thermal insulation, please click here.

Benefits of installing energy rated windows: Choosing windows incorporating a low-e glass such as a glass from the Pilkington K Glass™ or Pilkington Optitherm™ ranges helps to prevent heat from escaping through the windows, reflecting it back into your home.

Specify your projects quickly and easily with Pilkington Spec-it! If you know the target U and g values for your project, then Spec-it! can help you select the right product. Two clicks to Spec-it!

Install low emissivity (low-e) energy-efficient windows to help to reduce your heating bills by up to 20% each year. Using a product from our energy-efficient glass range in your windows will reduce your home’s CO 2 output, making your carbon footprint smaller and your home more environmentally friendly.

Pilkington Optitherm™ S1 Plus Pilkington Optitherm™ S1 Plus is an off-line coated, single stock product, offering superior thermal insulation performance with Ug-value of 1.0.

Better insulation and no cold spots near windows make Pilkington K Glass™, Pilkington K Glass™ S and Pilkington Optitherm™ S1 Plus an excellent choice for conservatories, because thanks to a special low emissivity coating on the surface of the glass, it lets the sun's rays through, but reflects heat from fires and radiators back into your ...

Reduces solar heat gain and offers high levels of natural light to provide comfortable and pleasant environments in which to live and work. Improves the energy efficiency of domestic or commercial buildings whilst enabling the extensive use of glass and the benefit of passive solar gain.