The fifth in our series of Design Case Studies with Altherm Window Systems visits the Auckland family home of architect Dave Strachan (of Strachan Group Architects), a former bungalow that's had a significant renovation with increased energy efficiency one of the primary goals.  The photographs are by Patrick Reynolds.

You could say that architect Dave Strachan has a 360-degree view of the process of designing and building a home. He was a builder before he went to architecture school and, along with his wife Colleen, he was his own client when he designed an extensive renovation of the couple’s bungalow in the Auckland suburb of Mount Eden (he also had to supervise his sons, who worked as builders on the project). This led to a mild case of multiple personality disorder. “When you’re the client, the architect and the builder, you wonder who’s calling the shots,” Dave says. “The client wants to know how much it is, the builder wants to know if you can do it easier, and the architect is reaching for the sky.”

Dave Strachan's family home in Auckland is a bungalow that's had a significant, environmentally senstive renovation.
Of course, performing these roles simultaneously saved the couple a lot of money. Their original bungalow was 180 square metres, but now the extension is complete, Dave and Colleen (who at the time had all four of their children living at home) have a renovated home measuring about 300 square metres in size.
The home before renovations began.
A view of the home after renovations were complete.
They initially explored the option of demolishing the bungalow and starting anew. Dave estimates that if a client was to pay a builder and an architect for an all-new home of that size (which includes a swimming pool), they would be looking at a bill of about $900,000 (plus the pool). In this case, Dave and Colleen completed the job for about $500,000. “I reckon we’re about $400,000 better off because we decided to keep the old bungalow,” he says. “And I think there’s something really nice about the embodied memory that’s still in our building – the heart of it still beats.” Part of the savings came from doing so much of it himself, but Dave still estimates that if a client was to undertake a similar project, they would save about $250,000 by keeping an old house.

The home's two-stage entryway features a garden
inside the building envelope that leads to the front door.

Two of Dave Strachan's conceptual sketches for the renovation.

A new indoor-outdoor living area at the rear of the house faces northwest and is usable year-round.

Dave does a budget estimate for a client himself at the sketch design stage, but calls in an independent quantity surveyor to estimate the cost of a build once the design has been developed. The biggest challenge, Dave says, is marrying clients’ wish lists to their budgets – and if they don’t match, letting the clients know quite clearly at the outset of the process that what they’re asking for is not achievable. The clients then have the option of scaling down their desires, or finding the extra finance to meet the budget.

The cliché that anyone taking on a new building project should estimate their budget then double it is, Dave says, “a horrible thought”. He prides himself on making clients aware of the full scope of potential costs at the outset of a project, including council and resource consent fees, building in a contingency for landscaping, and so on. If a client asks for something outside that scope, Dave says they need to be informed that such a decision will have budgetary implications. It’s a process that has worked successfully for Strachan Group Architects – a house they recently designed in the Auckland suburb of Parnell, for example, has a developed design budget (by a registered quantity surveyor) that is consistent with the original project estimate. “We’ve lost jobs where people have come in with a budget and we’ve told them it’s unrealistic, and they’ll go to someone else who tells them what they want to hear,” he says, “but you have to be honest with people about the process.”

The home's main bedroom looks onto the back lawn. The lightshade is by David Trubridge.
Q+A with Dave Strachan

HOME What was the hardest part about the process of renovating your own home? 
Dave Strachan We decided, rightly or wrongly, to live in it while we did it, so we put up with all the dust, mess, noise, and camping and decamping as you move around the building as various phases get completed. I remember lying in bed during a terrible storm after we’d pulled off as much roof of the old bungalow as we could cover with a tarpaulin and listening to the tarpaulin flapping around in the wind and finding water coming down the Gib board inside. With the design, I relied on the team at the office – you can get too close to a project like this, so it’s good to have people to talk to. 

Architect Dave Strachan.
HOME Does your background as a builder help you gauge a budget more accurately? 
Dave Strachan In general, you know how much everything costs. But we don’t do budgets with guesswork – in the initial stages, we calculate them by using the price books in our office. And we have a good feel for it and a collaborative approach with the builders we use. 

A view of the home's new living area with pool outside.
HOME What do you think of the old cliché that if you have a budget for a project, you should double it to get a realistic figure?
Dave Strachan I reckon there’s no excuse for that. The budget needs to marry reasonably well with the clients’ wish-list at the outset. After that it’s about knowing the budgetary consequences of the decisions the clients make, and informing them of that. We get a quantity surveyor in at the developed design stage and we don’t proceed with a project unless the client sees those cost estimates and says that they’re OK. Sometimes clients’ budgets don’t really match their dreams, and they don’t often admit that. A lot of it is about having a reasonable budget to cope with the scope that you intend.