In this week's episode of Grand Designs, a couple seeking a bright new start to their lives defy architectural conventions with a black-clad home made of steel-framed cubes with few windows, located deep in a shady Essex forest.

Artist Michelle Parsons was recovering from cancer when she decided to quit teaching and focus on her own art in a studio that met her exacting specifications that was far away from the rat race.

"Being ill made me realise that you've got one life, and you can't wait until you retire to live it," she says.

After a three-year search, the couple found a 0.25-acre plot of woodland in Billericay, Essex, and bought it for £200,000.

With a building budget of just £230,000 from savings and a self-build mortgage, her husband David, an architect, set to work on designing a studio with a house attached, rather than the other way around.

The studio has a vast north-facing window angled up to the sky, providing perfectly consistent light for an artist, who, unlike most of us, doesn't crave direct sunlight, but instead needs "soft, reflected light". 

The three-bedroom house is formed of three intersecting steel-framed cubes, clad in black timber and with no windows on the north or east sides.

Michelle says the lack of windows are because she wanted complete privacy from the outside world. However, once inside, a corridor lined with white bookshelves leads to an open-plan living area positively bathed in light. A feature wall was built from bricks from homes demolished to make way for the Olympic Park in Stratford.

The double-height windows in the living room illuminate as far back as the kitchen, which has black units, but a centrepiece polished concrete island that was designed and poured by David. 

Skylights illuminate other areas and, perhaps perversely, the smallest room in the house is the brightest - the bathroom is lit by a glass roof, giving total privacy but a breathtaking view of the trees and the sky.

On the house's flat roof, the couple planted tiles of sedum, which when in flower are a magnet for bees, reflecting their desire for their home to blend in with its surroundings.

The master bedroom gives a view across the green roof and into the forest. "It's an infinity garden," says Michelle.

The plot is in the heart of an area that in the Twenties and Thirties attracted Londoners seeking a new life in the country, when small pieces of unwanted farmlands were sold to so-called Plotlanders, who built their own homes.

Indeed, the Parsons' plot itself was home to one of these shacks, and although their home is far from being so basic, it does mirror the black tar-clad barns that still exist in this area of Essex.

Even on their tight budget, David didn't want to disturb the forest unduly and spent £60,000 on groundworks alone, building the house on piles that affected the trees' roots as little as possible, covered in a honeycomb polystyrene membrane that prevents the concrete floor from being disturbed by the shifting clay earth below.

Michelle says: "It's honest, it's truthful to us. It's by us, for us. "I think everyone should build one house in their lifetime."

Grand Designs presenter Kevin McCloud says of the building that while many people might want their dream home to be "awash, flooded" with light, it was a "perfect fit" for David and Michelle, an "autobiographical" home that addresses the tensions not only within architecture but ourselves, that explores the "terrors of the wood and order and safety of the home".

Grand Designs is on Channel 4 at 9pm on Wednesdays.

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