Period powerhouse

"We were drawn towards the large windows and well-proportioned rooms"

Nils and Lisa Feldmann transformed their leaky 1870s period property into a warm and energy efficient home, focusing mostly on insulation.

"I'm a firm believer that if you insulate your house properly then that's the best way to keep your running costs low," says Nils, an architect. "Once installed, insulation doesn't need maintenance like other technologies, so that's where we invested our money."

It was clear from the start this handsome detached house in Leicester was going to need some serious renovation work. But the couple could see beyond the decay and had a sense of what the property could become. "We knew it had once been a very grand house," says Nils. "We were drawn towards the large windows and well-proportioned rooms."

The couple took ownership in July 2012 and Nils got to work on the drawings. His first priority was a new kitchen-diner, which he designed into a timber-framed building on the footprint of the old double garage. They also decided to replace the rotten 1970s extension and use the second timber frame building as their office.

Once the Feldmanns had planning approval, Nils put the project out to tender to three builders, one of which was Rockingham Construction. "James Barby's enthusiasm impressed us from the start," says Nils. "He was keen and very organised."

The project began in April 2013. The house had to be stripped back to a bare brick shell but without cavity walls to fill with insulation, it needed an external insulating render system and internal insulation.

Nils says James was very good at embracing the new technologies and they appreciated his diligence, including undertaking the necessary training. For example, the team learnt how to install the insulating floor system as well as the external insulating render system.

"It was the first time we'd ever used any kind of external insulation system," admits James. "To complicate matters further, planning restrictions meant we could only insulate areas not visible from the street so we had to ensure the differing materials aligned with one another."

"It's a lovely warm space"

Nils hoped to complete the project on a budget of around £300,000 but, inevitably in a house like this, they uncovered the unexpected along the way. "We had to replace a lot of floorboards, plaster almost the entire house, and underpin the weak foundations at the back," he explains.

The construction of the two new extensions were more transparent, built from highly insulated timber frames filled with blown cellulose insulation, and green roofs constructed from metal webbed posi-joists, finished in sedum.

The Feldmanns' house was finished in March 2014, restored to its former glory yet enhanced by the contemporary additions that delineate the old from the new.

The effort has been wholly worthwhile. "Hopefully we've restored the grandeur back into the property," says Nils. "It's a lovely warm space - we get out of bed every morning with a smile on our face!"

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