Choosing Rooflights

When Rooflights Are Best

Rooflights are the perfect way to introduce natural light into areas where conventional windows cannot be installed, or would be aesthetically obtrusive. Loft conversions are an obvious example – where rooflights bring in around 40% extra light than dormers – but also lean-tos and dark corridors, where a continuous run of rooflights floods the space with light.

However, there are also instances where you won’t have any other choice, such as barn conversions, where strict planning laws often prevent the insertion of new openings, as Matthew Slocombe of SPAB advises: “Sympathetic detailing is likely to be a condition of consent, especially if the barn is listed or in a Conservation Area. New openings should generally be kept to a minimum and should be of a simple form that respects the farm building’s character.”

Paul Trace, Managing Director of Tuscan Foundry Products, elaborates: “In this situation a conservation rooflight would be required as they are especially designed with a low profile. This means the rooflight will sit flush and not detract from the character of the building. Steel conservation rooflights are ideal as they are made specifically to provide slender sections which are unobtrusive.”

Steel conservation rooflights are designed to replicate original Victorian models – the period in which they were invented, for agricultural buildings – and have a glazing bar. As well as many barn conversions, they are a requirement in a lot of houses that are listed or in Conservation Areas.

Which Type of Rooflight?

The term ‘rooflight’ has several meanings within the window industry. Many presume the Velux-type windows — but when H&R recently asked Velux about its ‘rooflights’, the initial response was, “Sorry, Velux doesn’t do rooflights — just roof windows.” Meanwhile, dozens of glazing companies claim their glass ceilings are actually rooflights. So when you start to think of rooflights as simply a way of introducing daylight from above, the term starts to make a lot more sense.

There are several types of rooflight, both fixed and opening — referred to as ‘in plane’ or ‘out of plane’, depending on whether they are flush, like the Velux type – installed in either a random, chequerboard fashion, or evenly spaced upon a mid-roof slope – or raised sculptural lanterns. Typical bespoke sculptures are pyramids, pitched polygons, barrel vaults, ridgelights and vertical glazed panels. But the options don’t end there. Rooflights can serve as viewing boxes at the top of staircases, or as openings onto roof gardens — you can even specify flush, walkon rooflights if you’re brave enough.

Materials

Your rooflights’ material must work in close complement with that of your windows. Metal is perfect for period properties, barn conversions and sleek, contemporary houses alike, with both steel (often required for barns and homes in Conservation Areas) or aluminium being the options.

Timber is a long-time favourite on homes of any style, but getting onto the roof to maintain the timber can be an awkward task, so consider timber-aluminium composites, which offer the look of wood inside but are lower maintenance outside. PVCu is an option, but it will not provide the slim frames that metal is capable of, nor the natural look of wood. It is, however, inherently low maintenance.

Whatever the material, rooflights must be fitted to allow water to drain away. Weatherresistant flashings can be visually obtrusive but are essential to avoid leaks. Ensure they complement your roof as closely as possible.

Operation

The simplest and cheapest opening rooflights are operated manually, with a pole. For around £200 extra a window, you can install rooflights with a basic electronic opening system, controlled by a remote control or wall panel. They can also be integrated into a whole-house setup — more advanced options include weather and fire sensors.

Lightpipes

A more discreet way of bringing light in from above is the lightpipe. These are aluminium tubes with an internal mirror finish that intensifies and reflects natural light, which is evenly diffused around the room by a ceiling fixture. Lightpipes can be any length and will twist and turn around bends — fitting in between rafters and roof joists. You have the option to sit halogen lights inside the tube, and a black-out diffuser will prevent you being woken up at the crack of dawn. Some models incorporate ventilation which can be solar powered.

In the gallery:
1 Tuscan Foundry Products’ steel conservation rooflights start from £359 + VAT (01409 255120);
2 Bespoke frameless rooflight by Glazing Vision, POA (01842 815581);
3 Velux INTEGRA® electric roof windows are remote controlled and programmable, from £506 incl VAT (0870 166 7676);
4 Monodraught’s Sunpipe is a less obtrusive way of bringing light in from above, from £631 + VAT (01494 897700);
5 Made-to-measure glass roofs from Cantifix can be ordered online and installed by competent DIYers, POA (020 8203 6203);
6 Fakro’s vacuum-impregnated pine, coated with a white polyurethane varnish, POA (fakro.co.uk);
7 Bespoke glass rooflight with sandblasted stencil, from £1,000 by Ion Glass (0845 658 9988);
8 Extra-large conservation rooflight on a listed barn, POA by The Rooflight Company (01993 833108);
9 Octagonal Skyline Skylight from Glazing Vision, POA (01842 815581);
10 Glass roof for an extension to a listed property by Apropos Tectonic; similar will cost around £12,000 (0161 342 8200).

Advice from the Experts

Maximising light
Kevin Brennan, Head of Sustainability, Velux Company Ltd (0870 166 7676)

“As a general rule, you need to provide glazed areas equivalent to 10% of the room’s floor area to achieve adequate daylighting. The overall effect is improved dramatically by increasing this ratio to around 20% and also by using several smaller windows rather than one or two large ones. When a new extension is built the room is usually longer, meaning daylight has further to penetrate into the house. With rooflights you can make the room feel brighter, larger and more welcoming.”

Design Possibilities
Paul Trace, Managing Director, Tuscan Foundry Products (01409 255120)

“Although conservation roof - lights authentically replicate a traditional Victorian design for period properties, their low profile and fine lines of steel have infinite design possibilities with modern-day architecture. They also benefit from having high specifications of glazing, including self-cleaning glass. And not only do they provide a solution to lighting up dark areas, but they are energy efficient due to the amount of natural light they let in, which in turn will reduce energy costs.”

Further reading:

• A Guide to Choosing Windows & Doors for Your Self-build
• A Guide to Positioning Windows
• Dormer Windows: How to Get Them Right