Profile 22 approved commercial manufacturer, Polar Windows has aided the £4.5million regeneration of 70 flats at Stonelow Green in Dronfield, supplying a casement window solution using the Profile 22 FI70 system. Over an 18 month period Registered Provider and housing management company for North East Derbyshire District Council, Rykneld Homes completed a comprehensive refurbishment on the five blocks of flats (70 homes).
Principal contractor, Morgan Sindall required local contractors to be used wherever possible.
Just seven and half miles from site, Hasland-based fabricator Polar Windows was appointed preferred window sub-contractor due to locality and the company’s proven experience in the commercial sector.
“We wanted to secure the future of the blocks through a long-term solution not a rebuild,” comments James Lindsay, assistant contracts manager for Rykneld Homes. “…while also improving tenants’ quality of life and lifestyle.”
There were a number of key drivers behind the refurbishment; improving energy efficiency and reducing maintenance costs were both high on the list. “Energy costs were an issue for many of our tenants,” continues James. “Reducing fuel poverty is part of our Business Plan 2014-17; the improvements at Stonelow Green go a long way in achieving this.
“We were also having to carry out frequent repairs so low-maintenance, future-proof products formed an important part of the specification. The windows are a good example of this. The original windows were early 1990s PVC-U. They were side-hung and very large which meant that the hinges failed. There were no trickle vents either so that contributed to some damp issues within the flats.”
Polar Windows’ business development manager, Rob Hawkins explains how the window solution helped eradicate cold spots within the building, and worked with the external wall insulation (EWI) to improve the thermal performance of the blocks. “Our biggest challenge on this project was the large lounge windows. A vast PVC-U tilt and turn window had originally been combined with a timber panel to create a long feature window. While Rykneld wanted to retain this aesthetic, for uniformity across the blocks, like-for-like replacement would have meant unnecessary cold spots. We had to design a window solution which would allow as much of the building to be wrapped in EWI as possible.
“As the tilt and turn windows weren’t popular with either Rykneld or the residents, we opted for a 50/50 split casement window with a vertical mullion and push out window. We also shaved 100mm off the height simply because window design has come on leaps and bounds since the early 1990s, and we’re able to work with slimmer, improved PVC-U profiles nowadays.
“To achieve the same look we retained a 50/50 window/timber panel composition but rather than simply fixing plywood panel beneath the window or skimming plasterboard we fastened the timber panel to a PVC-U frame with two vertical mullions fabricated with the Profile 22 FI70 system.
“Using a specific screw, (a factor that we had to stress on-site) combined with Profile 22’s recycled composite material (RCM) reinforcement we were able to achieve the necessary wind load calculations, proving that the substrate was strong enough to withstand the pressures at height and carry the EWI.
“While we had solved the issue of the timber panel we also had to work out how the EWI could wrap around into the external reveal,” continued Rob. “For this we used tanalised timber, this meant that the EWI operatives could go right into the reveal and again, eradicate another potential cold spot.”
Rykneld Homes and the Council worked with the Stonelow Green residents, the local community and planning authority to choose a tonal colour scheme for the blocks. The new windows, in grey, complement the fresh rendered exterior, a combination of white, honey and terracotta tones.
“We completed the project on time and in budget,” continued James Lindsay. “With the regeneration of Stonelow Green we have improved tenants quality of life, future-proofed the blocks and reduced our repair and maintenance expenditure in the short and long-term.”