Let's find what you're looking for

    Achieving sustainable building
    design using rooflights

    arrow Back to blog 16th August 2017

    Natural light is one of the most freely available natural resources you’ll find, with the ability to transform the environment within any property.

    Rooflights fitted onto flat roofs can save tremendous amounts of energy on artificial lighting and provide excellent thermal performance to retain heat in the winter months and reflect the sun’s UV rays in the summer due to their sustainable building design. Rooflights also ensure an even distribution of daylight into interiors below, creating an invaluable feeling of space in even the cosiest of living spaces.


    Rooflights and reducing carbon footprints

    It’s been independently proven conclusively that rooflights are an effective choice for sustainable building design. De Montfort University’s Institute of Energy & Sustainable Development probed the effect that rooflights have on the total energy required to operate a building, as well as the yearly carbon dioxide emissions resulting from it. The research found that by installing an appropriate level of rooflights (between 15-20% of the total roof area) will lower energy consumption and the associated carbon dioxide emissions.


    The key conclusions of the study were that, in buildings used 24 hours a day, there were CO2 emissions savings of up to 15% in all cases where the rooflight area increased all because of the sustainable building design.


    For those designing living and working spaces, it’s important to note that artificial lighting is carbon inefficient, relying on power generated from the burning of fossil fuels. Although artificial lighting will be a necessity in certain parts of the day in the workplace or home – certainly during winter months – it should be controlled by automatic operation on an at-need basis i.e. when daylight levels fall to a specified level. In the winter months, rooflights continue to be effective however, by delivering passive solar gain that can reduce energy costs.


    Rooflights and types of daylight

    Not only can rooflights encourage abundant levels of natural daylight into a building they are also capable of influencing the type and amount of natural light that can filter into interiors below. This relates to direct light and diffused light, which both have their benefits, and should be considered by architects and designers when determining rooflight areas and the use of spaces below.


    • Direct light Rooflights can filter natural light directly through the glass surface, without any interference of disruption. This is filtered as a straight beam, giving impressive levels of daylight to interiors directly below the rooflight but less so in the surrounding areas.
    • Diffused light This relates to the scattering or diffusion of natural light into interiors below, resulting in a more even distribution of light. This is better suited for spaces requiring effective ambient lighting rather than strong light for close detailed work or in environments that need to appear very natural.

    Rooflights and thermal sustainability

    Part L of Building Regulations state that all architectural rooflights must have U-values of 2.2W/m2K or better. Meanwhile the limiting fabric parameters set limits on the worst acceptable standards for insulation values for the building fabric of new dwellings at 2.00W/m2K for rooflights.


    This covers the following:

    • The area weighted average for all elements of that type. E.g. if one opening and two fixed rooflights were installed to a property, the opening rooflight may be permitted to have a U-value greater than 2.00W/m2K, so long as the fixed rooflights have a much better U-value, resulting in an overall average U-value that’s within the 2.00W/m2K limit.


    Building Regulations also define ways to limit the affects of heat gain. Although it states limiting glazed areas such as rooflights as being one solution, it’s not necessary to take such drastic steps given the availability of solar control glazing. This allows daylight to pass through a rooflight whilst radiating and reflecting much of the sun’s heat and rays outside; thus maintaining pleasant temperatures and environments below and mitigating the need for expensive air conditioning.

    Rooflight standards and testing

    At the time of writing, there remains no harmonised European or British-specific standard for rooflights on flat roofs. As such, the only way to prove suitability, performance and compliance is to gain certification from an independent testing organisation.


    The British Standards Institution (BSI) agreed to test Sunsquare’s rooflights under their most rigorous Kitemark standards in a bid to achieve high-quality certification above and beyond CE marking and demonstrate safety, quality and sustainability.


    Achieving the BSI Kitemark and ISO 9001 demonstrates a mark of performance, surpassing the benchmark for extreme wind loading, weather tightness and air permeability. The process created a framework for efficiency that enables processes to be improved and tweaked continually.


    Sustainable rooflight manufacturing

    At Sunsquare, we take the environmental impact of our rooflight manufacturing processes extremely seriously. In fact, we’ve achieved certification for ISO 9001 and ISO 14001, demonstrating our environmental credentials and commitment to reduced waste and energy use.


    We’ve also employed a dedicated systems and quality manager, who is continually working to ensure we can add further value to our rooflights whilst removing waste from all our processes.


    The company has a strong reputation for rooflight innovation. You’ll find our display of state-of-the-art architectural rooflights at the BRE Innovation Park in Watford, underlining our com


    If you’re at the planning stage of a project and you’d like to discuss the prospect of incorporating rooflights into your building designs, please don’t hesitate to contact us to discuss your requirements in greater detail.

    Share this guide

    Want to know more

    If you want to know more about this or anything else then get in contact.

    Call us on 01922 714087

    Email sales@sunsquare.co.uk

    refine search


    28 April 2021

    Lowest U-Values in the skylight industry

    U-values are touted by companies as a selling point for their products. Until now, all skylight U-values are calculated in exactly the same was as a vertical window, which gives a false reading and misleads the client.

    Read morearrow
    The benefits of using BSI

    26 May 2020

    Desire for quality never stops

    In what has been one of the more traumatic times for British industry, Sunsquare, whilst not fully operational until beginning of May, have been busy during downtime. Our desire to continue to be the market leading in our field didn’t get locked down. Quite the opposite. Not only have we been testing product and designing, […]

    Read morearrow
    Self Cleaning Glass

    05 October 2019

    Thoughts on Brexit

    Obviously Sunsquare are not immune to industry trends, but it is comforting to see that the clients that have used our services over the recent turbulent months are citing quality and qualification as the reason for using the skylight budget with us.

    Read morearrow
    The importance of environmental management

    27 August 2019

    The Demise of a British Great | R.Durtnell and Sons Ltd

    We were very sad indeed to receive a letter a few days ago for the official receivers for R. Durtnell and Sons Ltd.

    Read morearrow
    Aero Pyramid Skylight

    10 August 2019

    Sing when you’re winning

    It’s been quite a few months for Sunsquare. New skylights launched, shows to shout about and a spanking new website to admire.

    Read morearrow
    Skylights and rooflights

    13 June 2019

    Another industry first for skylight pioneers Sunsquare

    Sunsquare has not only achieved the Kitemark accreditation for another 3 years, but the ISO9001 and ISO14001 accreditations with no non-conformities.

    Read morearrow

    Sunsquare Accessories

    Find out morearrow

    Sunsquare Skylights

    Find out morearrow

    Since 2004, Sunsquare Limited has been pioneering skylight design

    Call us on 01922 714087