Home of the month: off grid and on style
PUBLISHED: 10:51 06 April 2016 | UPDATED: 10:51 06 April 2016
A new-build Herts home that runs entirely on renewable energy is a leading example of off-grid, affordable, yet elegant construction. Pat Bramley meets the couple who have made their 'zero-energy' dreams a reality
By now Colin and Alison Heal will know if the timber framed eco-house they built in Blackmore End, a hamlet south of the village of Kimpton in North Herts, has won a prestigious award. As this issue of Hertfordshire Life was going to press they were among guests at a dinner at Hatfield House where the winners of the 2015 Hertfordshire Building Futures Awards were announced. To be on the shortlist of four in the category for Most Sustainable Construction was a significant honour in itself.
Alison is a physiotherapist, Colin a project manager in the construction industry whose forte is major commercial schemes in London. ‘I’ve worked in this industry for many years,’ he says. ‘Most people in the industry dream of building their own house. Not many get the chance. I did.’
The couple have lived in the area for 30 years. They improved both their previous houses. This is the first they’ve built from scratch.
Alison explains, ‘The plot we bought is about a quarter of an acre. There was a small house on it previously and I’d heard that the lady who lived here had died – she was 103. We got in touch with her nephew but didn’t hear anything. Then about five months later when we were on holiday in Italy we had an email from Strutt & Parker asking if we were interested and of course we said we were. The sale was completed in June 2014.’
In their 10-page submission to the award judges they state their objective from the outset was ‘to create an elegant, contemporary and sustainable family home which would be zero carbon in its use and simultaneously be an exemplar of modern design and methods of construction.
‘We hoped to demonstrate to the uninformed or non-believers that there are other ways to build new houses within an affordable budget, aside from using traditional materials which have significant environmental impact. We saw this as important because most lay people think bricks and mortar are the only way of building, and nearly all builders and developers still insist on using them.’
The house they built has five bedrooms over the two upper floors, four bath/shower rooms counting the wet room on the ground floor, an expansive open-plan kitchen/sitting/dining area with bi-fold doors opening up the interior to the garden and two separate reception rooms – a main sitting room which runs from the front to back of the house and also a study for Alison.
‘We knew how we wanted to live,’ Colin emphasises. Having produced a clear brief of the layout they commissioned London-based architect Paul Osborne, a specialist in sustainable buildings, to draw up formal plans to submit to the council.
The house took just eight months to build ‘from the day we started on-site clearance and demolishing the old house to the day we moved in,’ Colin says. Not surprisingly, given his line of business, he project managed the build himself, using specialist contractors.
‘Self-build not only reduced the overall cost but allowed for flexibility during construction. Site waste was kept to a minimum through recycling and careful ordering with only the bare minimum of non-recyclables going to landfill. Using a timber frame meant the construction was carried out much more quickly than normal (it went up in three weeks), which resulted in less inconvenience for the neighbours and a reduction in the number of vehicle journeys to and from the site.’
Despite being a modern house in a road of properties mainly built from the 1930s to the 1950s, not one complaint or objection was lodged during its construction.
The level of detail and consideration came down to tracking the sun’s path over the plot. The Heals had a 3D model made of the house to track the sun during the different seasons to decide the best orientation for rooms but also to identify how far the shadow of the building would affect the neighbouring house on the north side so they could adjust the position if necessary.
’Following discussions with our neighbour we brought it forward approximately two metres to reduce the impact on the rear of their house and instead of using the originally planned Canadian cedar cladding on the south elevation, we replaced it with white render to provide more reflected light into the north facing windows of the neighbour on the other side,’ Colin explains.
Due to poor ground conditions, the couple were told by their engineer at the start of the project that the house would have be set on concrete pile foundations sunk into the sub soil. Undettered, they used this as an opportunity to create one of the first houses in the UK to install pipes in the piles which connect to a ground source heat pump – the prime source for their underfloor heating and hot water systems.
‘It was a no-brainer not to use this dual-purpose technology,’ Colin says. ‘It was much cheaper than a large borehole or the ground loop which the heat pump system would otherwise have needed, but we only found one contractor who would do it.’
As a result, the house stands on 15 piles with four pipes in each through which brine warmed by the natural heat from the ground comes into the house. This, combined with 35 photovoltaic solar panels that form the roof on the south side of the building, two wood burning stoves and an automatic heat recovery and ventilation system which uses heat from expelled air to warm incoming fresh air add up to a property which not only banishes fuel bills but supplies an income from excess power sold to the National Grid.
Natural light is the other main feature of the home. It floods through glass walls that form the structure on the ground floor and through roof lights on the top floor which allow light to stream down the stairwell to the hall. The open-plan design means the light flows through the house. ‘You can stand at the front door and see straight through to the back,’ Alison says with delight.
Almost everything in the house has a story. Hardly any material from the original property went to landfill. The joists and rafters were reused to build the garage and the bricks were recycled as hard core. The kitchen was hand-built by a local family company, John Ladbury of Welham Green near Hatfield, using innovative worktops made of recycled bottles, TV screens, mirrors and clam shells. And the pitched roof consists of the photovoltaic tiles on one side and salvaged slates on the other. There is also a green flat roof above the kitchen planted with sedum.
When Alison’s friends heard she and Colin were planning to build an eco-friendly house they assumed she’d be throwing out her antiques. Not a chance. ‘They thought you couldn’t have antiques in a contemporary house but I believe you can mix any style of furniture in a modern setting with the right décor. I never throw out anything if it still has a use.’
She feels the same about choosing plants for the newly-landscaped garden. ‘One of the things I was sad about when we left the last house was leaving behind plants I’d been given. I’m hoping friends will pass on seeds and cuttings for our new garden – it gives you so much pleasure when plants and things you’ve loved in the past appear like old friends in a new house.’
HOW IT WAS BUILT
Architect: Paul Osborne, email@example.com
Ground source heat pump, underfloor heating, mechanical ventilation and heat recovery system: BeGreen Systems, begreensystems.co.uk
Solar Panels: Solinvictus, solinvictus.co.uk
Timber Frame: Merronbrook, merronbrook.co.uk