Healthy energy performance

With its newly extended headquarters in Alfreton, Derbyshire, Slimming World wanted to create a landmark building for the brand that would both provide an ideal working and training space for its people and deliver excellent environmental performance.

Glazing plays a key role in the £8.5 million scheme, both aesthetically and in terms of its use of energy.

At the heart of the building is a large atrium with a full-height glass front elevation and a glazed roof running right to the back of the space. Meanwhile, one of the wings connected by the lobby area features large ‘picture windows’ that deliver views over the facility’s attractive, leafy grounds.

Because much of the building’s envelope is glazed, the designers faced the challenge of avoiding the need for an energy-intensive climate-control system to create a comfortable environment for users all-year-round.

Lee Shaw, business development manager at Pilkington UK, said: “The twin challenges any building with extensive glazing faces are loss of heat on cold days and excessive heating as result of direct sunlight when the weather is warmer.

“The combination of products we have supplied to this project use advanced coatings cleverly to minimise these two effects, helping to smooth out the peaks and troughs that can lead to uncomfortable temperatures, expensive heating and air-conditioning bills and wasted energy.”

The curtain walling system uses double-glazed units manufactured by Pilkington, incorporating Pilkington Suncool 60/31 T solar-control glass and Pilkington Optitherm S1 Plus, a low-emissivity product.

The solar-control glass features coating that transmits only 31% of the sun’s energy, while still allowing for 60% light transmittance, so that occupants still get a clear view outward.

The low-emissivity glass meanwhile features a coating that reduces outward radiation of heat, so that less is allowed to leave the building on colder days.

The same glass is used in the atrium wall and roof, but is held in place using the latest structurally glazed units from Schueco. These deliver glazed surfaces with ultra-low-profile frames to minimise interruption of views from the building, as well as daylight flowing into it.

Extra strength is added to the atrium glazing by including a layer of laminated glass on the inner pane, to help the large units stand up to forces exerted on them by the wind and potentially the weight of snow during the winter.

“This project demonstrates the range of glazing solutions we are able to offer, with a combination of curtain walling, structural glazing and roof glass, all of which has been manufactured in the UK,” Lee said.

“The architect has used timber slats to deliver some degree of solar shading, but the extensive area of glazing enclosing the space means there would still be significant risk of excessive heat build-up. The glazing specified minimises this effect, saving energy and money while also delivering a more comfortable and stable year-round climate for those using the building.

“This is also one of the first projects to feature Pilkington Suncool 60/31 Pro T glass, which is now fully manufactured in the UK, following recent re-location of production from Germany. It’s great that we’ve been able to combine a made-in-Britain success story with a new chapter for a well-loved British business.”

The new headquarters includes extensive training facilities, meeting and office spaces, as well as a brand new 550-seater restaurant for staff, guests and consultants visiting for training.

Paul James, Slimming World’s facilities manager, says: “Having large expanses of glass has provided us with a beautiful, light-filled space that will be comfortable and inviting for everyone who uses the building right through the year.”