Heating and insulation help winter moods

Architect Max Capocaccia, left, and geotechnical engineer Jan Kupec at the Kupec home, which is heated by geothermal energy.
Mick Stephenson

Architect Max Capocaccia, left, and geotechnical engineer Jan Kupec at the Kupec home, which is heated by geothermal energy.

Combating cold winter nights seems a constant battle, one that residents like to win when they retreat inside. 

Recent headlines include zero temperatures throughout the South Island, with a few places plunging beyond 20 degrees below.

The trouble is many people in New Zealand do live in substandard homes in terms of insulation and building standards, so the war to retain warmth can be difficult.

HRV chief financial officer Robert Bell, right, with Jason Pratley - production supervisor of double glazing units.

HRV chief financial officer Robert Bell, right, with Jason Pratley - production supervisor of double glazing units.

If a home does have gaps, even those with the wherewithal to provide heating to the family find they are paying to heat air that then escapes outside.

Businesses with solutions to help protect against bitter temperatures make their strongest sales pitches in the months of May, June and July. There is plenty of cold calling by promoters of heating solutions to our house at least.

But Christchurch-based architect Max Capocaccia says insulation and heating solutions can be looked on as a long term investment.

Brought up and trained in Rome and moving to Canterbury in 2007, Capocaccia has designed a house that uses geothermal heating from the Port Hills, drawing heat out of the soil and below via a heat transfer system even in the cold winter months.

He says geothermal solutions, whereby water used for underfloor heating is partially warmed, are relatively common in Europe and the United States.

One of Capocaccia's early geothermal client's is Jan Kupec a geotechnical engineer working for Aurecon and sometimes seconded to the Canterbury Earthquake Recovery Authority.

Capocaccia says the Kupec family home on Mt Pleasant's volcanic hills shows what geothermal can deliver. The residence accesses the heat naturally stored in the earth to produce consistent, lower cost whole-home heating.

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Depending how deep the geothermal-piped water system goes, ground temperatures of between 3-4 degrees up to 15 degrees can be accessed. That means less electricity is needed to heat the water, later piped through the underfloor heating, or to heat air used for a heat pump.

"Geothermal heating needs to be combined with underfloor heating. And then you capitalise fully on the system, by adding appropriate insulation, good thermal mass ... to create a consistently warm house that doesn't need much energy to be heated," Capocaccia says. 

Kupec says when you build in a house you invest in the next 50 years. "Geothermal heating is a feature that sets the house apart if we sell it one day."  Kupec, his wife Dr Yaso Kathiravel, and family can walk in bare feet and t-shirts, regardless of the time of year.

It helped that Kupec is a geotechnical engineer, because their geothermal system required drilling 120 metres down into the volcanic rock in Upper Major Hornbrook Rd.

This is the less common, and more expensive, vertical bore system of geothermal heat exchange. The alternative, where enough land is available, is horizontal ground loops, where pipes are buried at shallow depths and can be landscaped over, Capocaccia says.

"The earth works for horizontal ground loops cost around $7000-$8000. Kupec's four bores on the other hand added about $20,000 to this project," he says. Underfloor heating systems within concrete slabs cost in the order of $10,000 per hundred square metres. 

"Two bores would have been sufficient, but rather than saving money Kupec opted to future-proof the home; if they add a pool in the future, the current system can heat it."

Houses in Christchurch that once had their own bores could potentially cap those bores to access the warmer temperatures, lower underground, he says. Capocaccia started in Christchurch working for recognised architect Ian Athfield before setting out on his own in 2010.

Geothermal did not need to be the domain of luxury houses. In Europe there are examples of multiple homes new subdivisions all tapping into the same underground heat source.

Geothermal may be out of the ballpark for some budget-driven Kiwis. Again a long term approach may help the overall warmth of a house year round.

Thinking close to home again, we have taken out a couple of log burners, put in one heat pump an HRV ventilation-heat transfer system, extra double glazing as well as fresh insulation under a new coloursteel non-leaking roof.

There are continuing costs to HRV, including the replacement of filters. Likewise heat pumps have to be maintained.

Retrospective double-glazing can be expensive to install as most home owners realise, but double glazing is standard in new builds.

E-Co Products Group (which trades as HRV) chief financial officer Robert Bell says his franchise-based company has spread its wings with the acquisition of part of a double glazing-windows treatment business, Energy Saving Centre, which went into liquidation late in 2014 year.

That means HRV, owned by an Australian private equity group Equity Partners and senior managers, can offer a number of insulation solutions to existing customers. There are 150,000 homes with HRV, Bell says.

While HRV had only retained the South Island staff of Energy Saving Centre, there are plans to expand the retro-fitted double glazing work into the North Island with $500,000 invested in reviving the business, he says. "I'd like to be in Wellington in the New Year."

Bell, with the group since 2010, has watched staff levels including sales and window fitting teams grow to 600 including 53 at the magnets-based glazing business as well as selling heat pumps. "So it's really a whole home solution, and that's a big focus for us."

Miranda James, spokeswoman for the New Zealand Green Building Council, says the council's recommendation is for home builders to think about heating and insulation right at the beginning of the design process.

"What we advocate for is to think about where you're putting your glazing, more on the northern side less on the southern side, and using a home layout which is going to be warm ... insulation is really a major, it sounds like an easy thing but there are still a lot of homes that are under insulated.

A new system in the market was "outsulation" building a home from scratch from panels that had the insulation material to the exterior of the building.

"New Zealand's becoming a bit more like the European market where people understand that a product with good thermal efficiency is what they want to go for," James said.

Energy Efficiency and Conservation Authority efficient products manager Eddie Thompson says heating is another component to healthy homes, with heatpumps having become a common source of radiation.

EECA is a government agency that works to improve the energy efficiency of New Zealand's homes and businesses, and offers some subsidised ceiling and underfloor insulation options for the elderly and those on low incomes.

The heat pump industry is starting to see a "levelling off" of sales given the huge number of devices already installed. EECA data showed that sales of "single-split" heat pumps into homes rose from around 32,000 in 2004 to a peak of 118,000 then 119,000 in 2009 and 2010 before retreating. Sales of 91,000 then 88,000 were recorded in 2013 and 2014.

"It's reaching a plateau now, one in four homes have a heat pump and now (sales) are starting to be the replacements," Thompson says. Warranties on heat pumps averaged around five or six years suggesting a life of 10 or 12 years.

"But I got phoned up by a lady who'd had hers 18 years and she was just looking for a new one." The latest models were a lot more energy efficient that heat pumps built in 2004, he says.

One of the key issues with heat was sizing the heater or heat pump to the space required. The use of cleaner wood burners is one trend, particularly in Canterbury where a lot of the older burners are needing to be replaced.


 - Stuff

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