A+ Energy Rated Windows
Here at TradeMark windows, we use a whole host of features to improve the performance of our windows, making sure we can do our best to help minimize your heating bills.
Back to Basics |
| How does double glazing work in the first place? In traditional single glazed windows, all that separated the warm inside and the cold outside is a single pane of glass. The glass does quite a good job of conducting heat from warm air currents within the home and then transferring it to the exterior. By introducing a second pane of glass into the window, a layer of air is trapped between the two panes of glass inhibiting heat loss – It works the same way a wool jumper does. This is because heat transference through convection (air currents) is far less efficient than through conduction (solid materials) – one of the few instances where we want something to be as least efficient as possible. |
Warm-Edge Spacer Bar |
 The spacer bar is the surface which runs round the rim of the glazing unit that separates the two panes of glass and seals the gap between them. As mentioned above, the way in which double glazed windows work is by hindering heat transference. This works great all the time the two panes of glass are separated. The spacer bar is traditionally made out of aluminium and since this is a metal, it tends to be quite good at conducting heat from the inside pane to the exterior. This doesn’t completely undo all the hard work that double glazing does since the relative surface area of the spacer bar is much smaller than that of the exposed glass – all is not lost.
By replacing the aluminium spacer bar with one made out of plastic, heat transference can be reduced further simply because plastic isn’t as good as conducting heat as metal is. |
Low-E (Emissivity) Glass |
 Emissivity is the ability of a surface to emit low levels of radiant energy. This is quite important in double glazing because part of the heat in the home is in the form of infra-red radiation. Glass is naturally quite good at emitting radiant energy and not very good at reflecting it. This means they’re quite good at re-emitting radiant energy inside the home to the exterior. To address this problem, the glass is coated with a thin metallic film which helps reflect radiant heat back into the home and inhibits thermal loss. |
Solar Heat Gain |
 Why heat your home all yourself when the sun can help. The special coating our glass receives allows solar heat to pass through the glass, into the home and then become trapped – free energy! |
Haze & Tint Free Windows |
 Pur windows maximises the amount of natural light into the home, without the haze or tint effects associated with some older double glazed windows |
