Satisfyingly sustainable

00:36, Jan 14 2013
Calderbank ecohouse1
WITH THE GRAIN: The home’s eastern aspect shows off the macrocarpa cladding.
Calderbank ecohouse1
WAKE UP AND SMELL THE COFFEE: Ali Lawley and Gary Calderbank with their son, Charlie, at the outdoor coffee bar.
Calderbank ecohouse1
INNOVATIVE: A family heirloom marble topped sideboard with carved boulder basin.
Calderbank ecohouse1
SNUG SETUP: View of the living space from the landing.
Calderbank ecohouse1
HOT DEAL: A Trade Me bargain helped complete the totally recycled kitchen.

Judith Ritchie checks a Nelson couple's second sustainable home build.

They say it takes building a couple of houses before you get it right. Ali Lawley and Gary Calderbank have just completed their second sustainable house since living in the Nelson area, and they are pretty happy with it.

Located just out of Nelson central city, they have a part-share of land at the Braemar Village. Having previously built a predominantly mud-brick house in the Ludd Valley, this time around they have opted for a more compact 135-square-metre, three-bedroom home with timber features and modern silhouette, finished with bright colours and many recycled fittings.

Gary, a mechanical engineer, designed the house, and did the original concept drawings, supported by input from specialists. Mark Fielding of Ecotect did the solar evaluation by mapping the path of the sun which helped decide the amount of glass (size of windows) for solar gain.

Architect Peter Olorenshaw worked on the concept plans, while Gavin Robertson was the structural engineer. Gary then project-managed the build while Nelson Construction Management, using two builders and an apprentice, built the house. Timberworks made the huge curved macrocarpa post and beam framing which span the living space, a wonderful eye-catching feature when entering this home.

The couple have always been keen recyclers, and that doesn't mean old and tired materials or fixtures. One major find on Trade Me was a complete kitchen which is in every way contemporary, with a combination of stainless steel, marble and timber veneer, and also included the cooker, fridge/freezer and rangehood. They estimate the whole kitchen cost them what the cooker would normally retail for, so naturally are very pleased with themselves.


One of their aims was to build the house to fit on to the naturally terraced then gently sloping hill, with plenty of storage inside as well as under the house. The back half of the house is on piles while the front is constructed using Polyblock, then two layers of polystyrene with concrete poured in between. Polystyrene has also been used on the ground in this front area, with a solar-passive concrete slab poured on top, polished, then finished with Osmo Polyx oil. Christchurch-made Terralana wool insulation was used in the thick 150mm untreated douglas fir-framed walls.

Ali put her woodworking skills into action at Waimea College's night classes by making recycled rimu shelving which fits into the wall spaces at either end of the stairs leading from the main living space up to the bedroom area. She also constructed the large family dinner table from the same rimu, again a second-hand find from an old shed at the Havelock marina.

Their love of natural materials is also evident with the use of macrocarpa weatherboard cladding, finished with CD50 tongue oil. The internal stairs leading from living space to the upper bedrooms and bathrooms are made from old school stairs from a recycling depot in Christchurch.

Gary also bought all the internal doors from a red-stickered house in Christchurch, then made the frames and architraving himself. Ali had a beautiful old family heirloom side table which now functions as a basin stand in one of their two upstairs bathrooms.

She says it was a bit nerve-racking cutting a hole in the marble top, but was worth it once the distinctive hollowed out rock-form basin was set in place.

Another focus for this family has been inside storage, with large sliding cupboards in 5-year-old son Charlie's bedroom, the fronts of the sliders functioning as a giant blackboard for Charlie and his friends. Along the carpeted (second-hand) passage way, well lit by clear-storey windows above, there are also large sliding storage cupboards, as well as a cleverly designed laundry with storage, hidden behind sliders in the entrance foyer.

Outside in the garden is a sunken 23,000-litre water tank, the flat concrete top currently doubling as an outdoor patio complete with table and chairs. Wastewater is separated into black and grey, with plans in the future to reticulate the grey water back into the garden.

Another future proofing has been wiring the house for photovoltaics, as they eventually want to go off-grid. LED lighting has been used throughout, with solar hot water using a 300-litre cylinder. Gary says the three of them clock up a monthly power bill of about $60.

They would prefer a woodburner for heating but are using a pellet burner, and find the house so well insulated and solar-passive efficient that they don't need much extra heating during winter.

Ali and Gary have clearly designed a home which is very sustainably sound while also being aesthetically pleasing.

By incorporating special places to retreat and sit, an outdoor coffee spot with servery directly from the kitchen, a master bedroom which takes in the restful rural outlook, and views of the twinkling lights of Nelson by night from the lounge, they have created a home with true ambience.