24 May 2016

Guidance and inspiration for rooflights


Rooflights are a great way to boost the levels of natural light in your home. Ideal for loft conversions, extensions or renovations, the possibilities are endless. Here, i-build provides some essential guidance and inspiration for these high-performance systems.


thumbnail image thumbnail image

While planning permission is rarely an issue when it comes to skylights, you need to take proper advice before you take out a section of your ceiling. When it comes to legislation, Sunsquare’s Managing Director, Justin Seldis comments: “In my line of work, wrangling over planning permission is less common than you might think. This is usually because a skylight falls in as part of an already agreed extension, or it’s a replacement of an existing window. But just because it is rare, doesn’t mean it doesn’t happen. So I have put together all the information available on this issue to ensure you don’t get into trouble.

“In England and Wales, the insertion of new roof windows is subject to the current limits and conditions stipulated by the Government’s Planning Portal. This comes under Schedule 2, Article 3, Part 1, Class C permitted development. That all sounds fairly complex but it boils down to this:

1. Any alteration cannot project more than 150mm from the existing roof plane.

2. No alteration can be greater than the highest part of the existing roof.

3. Side-facing windows must be obscure glazed with any opening to be made 1.7m above the floor.

“If your project fails to comply with one or more of the above, then your development won’t be permitted and a second application would need to be resubmitted following amendments to your plans.

“Generally pyramid or lantern skylights are more of a problem as they stick above the parapet and can create an eyesore to neighbours,” explains Justin.

Listed buildings

“If the property in which you want to install a new skylight is a listed building, or in a designated conservation area, then you should check with your local planning authority before carrying out any work.

“Additionally, there may be specific types of planning restrictions that mean certain works which could normally be undertaken will be the subject of control. It’s important to note that planning laws in Scotland are rather different than those in England and Wales,” Justin continues.

“Planning permission for roof windows is often required for even the most straightforward of skylight designs and Scottish property owners should contact their local authority to work out the best way forward.

“Similarly, homeowners in Ireland should also contact their local authority for advice because failure to obtain permission where it is required can result in penalties – including imprisonment.

Building regulations

Justin adds: “Building regulations are an issue quite separate to planning permission and should always be taken seriously. After all, the removal, addition or alteration of a skylight can have a detrimental impact on a roof which can, in turn, make a building unsafe. Even if planning permission is not required, building regulations cannot be ignored.

“By law, any building or structural modification work must comply with building controls which stipulate minimum standards for design and safety. There are two sets of building regulations for roofs – work on an existing roof and the construction of a new roof. Be sure to pay particular attention to Parts J and L of Building Regulations; these deal with energy efficiency, thermal insulation and the protection of buildings against the threat of fire.

“Approval under the Building Regulations will generally be needed for the installation of a new rooflight for the following reasons:

• To install a new rooflight, the roof structure will often need to be altered to create the opening.

• The roof will have to be able to carry the weight of the new skylight. If the roof is not able to do it will need to be strengthened prior to installation.

• Any rooflight installed must prove it has sufficient insulation against heat loss with effective energy performance.

• In the event a skylight is in close proximity to a boundary, its fire performance must also be taken into consideration.

Roof structure and performance

Justin continues: “To install a rooflight in a roof you will often need to cut part of one or more of the roof’s rafters or joists away. You will need to fit a new support for the cut ends of the rafter or joist in question. Adjacent rafters or joists may also need strengthening, as they will be supporting the load transferred from the cut rafters or joists.

“Any room that a skylight is designed to serve will also need to be well-ventilated. This can be achieved using the skylight itself for both rapid and background venting.

“In terms of energy performance, any window or door must comply with the minimum requirements of the Building Regulations in relation to the amount of heat that can pass through a window or door, including the frame. This is known and measured as a U-Value. This U-Value should not be exceeded,” concludes Justin.


Rooflights: The advantages

• Start with the basics - Daylight is free! It's an obvious statement, but few people actually take note that by utilising more natural light in their homes means a lower electricity bill.

• Now then, Mardy Bum - Studies have proven that natural daylight has a positive effect on mood. Daylight has been associated with improved mood, enhanced morale, lower fatigue and reduced eyestrain.

• Bye-bye mold - Most diseases, including chronic respiratory problems, are often associated with bacteria and fungi built-up in damp areas. With the ever-changing weather in the UK, it can be hard to avoid these things growing in dark, dank rooms without correct lighting. Natural daylight can decrease the production of these harmful annoyances.

• Beautiful buildings - Natural light is one of the most appealing lights, and is used by most interior designers to showcase a building in all of its glory. It can be a difficult technique to get right, but when it is used correctly it encompasses all of the above benefits whilst showing a home in its best light!


Wonderful ‘walk-on’ rooflights

A stunning 1930s detached property situated in the sought after borough of Golders Green in North London has been transformed during a full refurbishment programme. And, in order to bring the gloomy, traditional home to life and equip it for 21st century life, products from roof light manufacturer Xtralite were commissioned to bring natural light into the property. Of prime consideration during the project, was the necessity for the rooflight to be ‘walk-on’ and Xtralite was able to provide the perfect solution to this with its X Glaze traversable rooflight, which also delivered thermal qualities and strength. The walk-on units, which are able to be fitted directly to a builder’s kerb, comprise a 44.9mm double glazed glass system and a versatile monopitch which has a double glazing unit of 28.4mm. All units have a low E coating and are Aron filled to give a U value of 1.1W/M²Ko. In this case all frames were specially polyester powder coated to match the client’s choice of vertical glazing.


Historic barn breathes new life

When Mr & Mrs Shackle purchased a listed cottage and outbuilding in the heart of the historic market town of Cirencester, they had very clear ideas of the high standard in which it was to be renovated. Following extensive research for the most suitable rooflights to match their high specifications and to meet the requirements of the Conservation Department, the Shackles selected the Lumen Conservation Rooflight. This product, which authentically replicates a traditional Victorian design, is specifically designed for installation in period properties. With a low profile design and fine lines of steel, the Lumen Conservation rooflight blends beautifully with the modern day architectural look the Shackles were trying to create. Lumen rooflights also benefit from a high specification of glazing including Pilkington Activ self-cleaning glass, a solid American Ash timber liner and a choice of solid brass winding mechanisms for the interior aspect. It is these quality touches that have really impressed the Shackles.


Rate this item
(0 votes)
Login to post comments