Industry opinion

Was the light bulb the death of building design? asks Lee Marshall, Chartered Engineer and Managing Director of Viridis.

The invention of the light bulb was one of the worst things to happen to the construction industry. There is no disputing the economic and social impact it had on our lives. It allowed factories and businesses to run into the night, revolutionised our homes and social lives, and allowed us to travel safely in the dark. So much has been made possible with artificial light.

However, it led to the death of large, airy windows that let natural light flood in. Before the light bulb was introduced in the 19th century, properties were built to let in as much daylight as possible, thanks to the astronomical cost of oil lamps and candles.

In the post-war era, ceilings were lowered and windows became smaller because we could light our homes artificially. This continued into the housing boom of the 1950s and 60s and in the social housing growth of the 1970s and 80s. With the advent of LED lighting, our homes are more energy-efficient to run – not to mention warmer thanks to modern insulation and double glazing – but we haven’t updated our construction methods.

We need to not only start building better but also change our approach to how we build.

I believe that if you have a good, sustainable housing offering that is scalable then there is an opportunity to transform the market, but designs need to be more creative. For example, there is a huge waste of space and volume with traditional triangular roof trusses – you are probably losing 25-30% of the building for nothing. By lifting the first floor a few hundred millimetres and raising the bedroom ceiling further into the loft, you could push up ceiling heights in both floors and put in bigger windows, allowing in more natural light and passive heat from the sunshine, this creates some nice features such as vaulting as well as reducing the energy consumption.

Under current regulations, a window area must equate to approximately 20% of the floor area to allow a small amount of daylight. If this was increased to 40–50% and the minimum ceiling height regulated at three metres, it would transform how we live and improve health and wellbeing.

Learning from the past

We could also redefine our living spaces by changing the layout and geography of a house, which is normally dictated by the position of the stairs. If we put the stairs at the back of the property, then all the downstairs rooms could be at the front of the house. Would you even need windows at the back? It could be a north-facing wall that is timber-framed and well insulated. With bigger windows on the front, the bedrooms would be front- or south-facing, making the property a more rectangular shape, and you would have a larger, south-facing front garden that is accessible from both the kitchen and living area. If an entire neighbourhood is organised in this way, it gives privacy but maximises daylight – reducing the reliance on artificial light.

Many in the building industry have convinced themselves that people want a square house with a big roof and there is a reluctance to break the mould. I’ve been working in this industry for 20 years and understand it takes time to turn things around. Viridis is currently working on a selection of social housing that gives properties bigger windows and a higher floor-to-ceiling height.

The invention of the light bulb may have changed the way we think about building design but the energy revolution is forcing us to rethink those designs for the better.      

Find out more at

Lee Marshall Managing Director of Viridis. Viridis Building Services Limited specialises in providing sustainable, passive environmental building solutions that incorporate renewable, low-carbon, low-energy, HVAC and MEP systems for the built environment. 

Image credit | Shutterstock



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