By Lee Green, technical director at Kloeber UK Ltd
In the last few years roof lights and sky lights have featured heavily in building design and with good reason. Natural daylight is an essential element of any interior space but one that is still all too frequently overlooked. Often, a building will be designed with too much emphasis on its outward appearance and not enough on the interior experience, a major factor of which is light.
A couple of decades ago, the omission of light through the roof in the building’s design could have been excused as the options available for homeowners to bring the suns rays into their project were restrictive, of low specification and, let’s be honest, not too easy on the eye either. Fast forward to present day and the choice of options is vast with many different types of roof light, specification levels, bespoke design options and most with aesthetically pleasing designs at sensible prices. There is now a complementary roof light product for any project that will result in daylight, that wonderful natural resource, streaming into your interior, improving light levels and lifting spirits.
So which type should you consider? There are some important questions to ask yourself on the route to choosing the correct roof light for your project.
- What type of roof do you have? If you’re building a flat roof then you would naturally consider flat roof lights but pitched, hipped and lantern types might also be of interest. Flat roof lights usually have a minimal frame that is hidden from interior view. Large glass units can be specified in this situation leaving the occupier with an unhindered view of the sky, clouds and overhanging trees and architecture above. This is particularly effective when the roof light is positioned above a seating area like a dining table for instance or in a living room. ‘Walk-on’ glazing options mean that you can still use the roof as a terrace if you wish. Pitched roof lights are also an option here and, due to their shape, can often add an element of architectural interest to the design. If your roof is pitched and you have a vaulted ceiling then mono-pitched roof lights or even those that sit at the apex (ridge) of your roof will enhance your property. Due to their bespoke nature these will absorb a little more of your budget but you will be rewarded with a significant architectural feature as a result.
- How much light do you require? The size of your roof light will of course be one of the first considerations and one that is directly relevant to how much light will pass through it. Factors like rafter spacing and tile details will need to be taken into account here and your builder or roofer will be able to advise you on this. If your intention is for maximum light then try to avoid options with a significant amount of framing, such as lanterns and pitched types. These will allow less light through them than frameless types.
- Material type? The three main options here are uPVC, aluminium and timber. uPVC will be the cheapest of the three but in the case of pitched roof lights can sometimes look chunky and clumsy, especially if the roof light itself is small. Aluminium offers slim sightlines to maximise the amount of glass and is arguably the best option as it ticks the cost, design, size and low-maintenance boxes on your wish list. For properties that are of a more traditional design the timber option will be more appropriate.
- Do you require ventilation through the roof light? Will you require it to open? Whichever roof light you choose, it’s very likely that you will have the option of specifying it to open for ventilation purposes and in some cases, even for access purposes. Those of us that remember our physics lessons will know that hot air rises and, with built-in opening mechanisms, this air can be quickly released therefore avoiding uncontrollable temperature increase through solar gain in the living space below.
- If it opens, will it be accessible or will you require remote operation? If your roof light is within easy reach you may only require a handle or a manual winding rod. For less accessible situations, much better to specify a remote opening control via a switch on a wall or a hand-held remote controller or even temperature sensors for automatic opening and rain sensors for automatic closing.
- Which type of glass will you choose? Your chosen supplier will supply you with glass that meets the requirements of the UK Building Regulations, however there are additional choices. If your roof light is likely to be south facing then you might need to consider restricting the amount of heat passing through the glass from the sun to reduce solar gain. This can very easily be done by specifying solar-control glass, which can reduce the UV rays that pass through the glass itself by up to 80 per cent with only a small loss of light transmittance and at not much extra cost. Self-cleaning glass is another worthwhile option. It may not be as magical as its name suggests but, due to its coating on the exterior surface, it will encourage the rain to sheet down the glass taking most of the dirt with it and reducing the need for cleaning. Both this and the solar-control options should be available from all reputable suppliers.
Whichever of the above options you choose and whichever product you specify, you will undoubtedly enrich your living experience to the point when you will wonder why you didn’t do it sooner!