When choosing roof windows, the most important factor to bear in mind is durability. Here are some more aspects to consider
Quality of Materials
The quality of materials used will have a significant effect on the product’s performance, efficiency and the required levels of maintenance.
Environmental factors also play a huge part – rain, wind, and extreme temperatures will all take their toll, as well as exposure to ultraviolet light.
Internal conditions will also have an impact on window frames and seals, for example the humidity of the room, the moisture of the air, as well as the level of condensation. As the cost of heating is now a major priority for all homeowners, the focus is firmly on energy efficiency, not only because of rising costs, but also because of government pressure to reduce our carbon emissions.
If we want to install roof windows to increase the amount of natural light into a home, we can’t ignore the possibility of increasing heat loss. There’s no denying that when warm air from inside the property meets the surface of any window, the heat may be lost through the glass and dispersed into the surrounding environment.
Every building can lose heat to the outside world at a different rate. The rate of this transfer of warm air to the outside atmosphere is known as the U-value and is expressed in watts per square metre kelvin (W/m2K). Look out for a low U-value, as this indicates a well-insulated and efficient product.
As with all windows, double glazing ensures that heat is not allowed to transfer between the two panes. This effect is known as thermal bridging. There are products on the market that also include low emission coatings which are applied to the surface of the glass. These coatings reflect warm air back into the room.
Planning permission covering roof windows is not normally required, but any installation must adhere to the following:
– Any alteration to project no more than 150 millimetres from the existing roof plane
– No alterations to be higher than the highest part of the roof
– Side facing windows to be obscure-glazed and opening to be 1.7m above the floor