The Makings of a Healthy Home
Published 24 November 2022
The makings of a healthy home
Home sweet home. A place to relax and unwind, rest our heads after a long day and spend time with our nearest and dearest. But how do we do that efficiently?
Many homes in Aotearoa are notoriously cold, damp and generally unequipped to deal with the chilly winters, with Wellington being no exception to this. There are a few factors that contribute to this, but it can be summed as the classic kiwi “she’ll be right” attitude – we’re surrounded by beautiful coast and beach life, it’s supposed to be warm, right?
It can be daunting as a first homeowner, or even an experienced investor when looking at our homes – what improvements should we make, what makes the most sense, where do we start?
While there’s no one size fits all approach to housing, the following is a handy general guide on where to begin, and why.
If you want in-person advice, book a home energy assessment today.
The three key components to a healthy home
There’s lots of things that intersect when making your home as efficient as possible, but the primary considerations can generally be summed up in the following three categories.
Thermal retention
Adequate heating
Moisture mitigation
As well as making your home warmer and healthier, an efficient home will consume less energy, saving you money and reducing carbon emissions. New Zealand's built environment is responsible for 20% of the country’s carbon footprint.
1. Thermal retention
When it’s cold out, we want it to be cozy inside, and any heat that we generate in a home, we want to stick around as long as possible. Therefore, thermal retention is at the top of our list.
In any home, look at insulation first, particularly in the ceiling, as warm air will escape upwards before it goes anywhere else. With close to a third of all generated heat being lost through poorly insulated ceilings, this is your ideal starting point. While heat loss through an uninsulated floor is much less (approx. 10-12%), it can be prudent to do both at the same time if possible. Uninsulated ceiling and floors can account for 40% or more of your overall heat loss, and many insulation providers will offer package deals when taking care of multiple areas.
Glass is your next biggest source of heat loss, equal to the ceiling regarding percentage, but lesser given warmed air will travel up before travelling out. Double glazing is an incredibly effective solution; however, it tends to be a much higher up-front cost when compared to other measures that can be undertaken. The suggestion here is that you double glaze if within your budget, and other key areas of heat loss have already been completed. There are lower cost options, with window film kits, magnetic secondary glazing and the like, all of which work well. A good starting point is to ensure all windows have good double layered, floor length, well fitted curtains, or cellular honeycomb blinds, both of which can come very close to the performance entry level double glazing can achieve.
Walls are next, accounting for around 25% of your home’s total heat loss. Unfortunately, many NZ homes do not have wall insulation and it is difficult and expensive to retrofit. The suggestion here is to install wall insulation into any room that is renovated, or engage a company that deals in keyhole dry fiber injection methods. Please note that if you’re undertaking wall insulation DIY, you will require council consent.
2. Adequate heating
Having the right heating in the home is incredibly important and is unfortunately where a lot of Wellington homes fall short. According to the World Health Organisation, 18°C is a healthy temperature for any room being used – higher for children, the elderly and people who are ill.
There are many options on the market to suit your homes layout, intention, and design., Once again, while there isn’t a one-sized solution to all homes, the following will suit the vast majority.
Heat Pumps
Heat pumps are incredibly energy efficient, being able to both heat and cool a space, as well as dehumidify. Solutions can range from traditional single room installation to multi split units all the way up to discreet central heating. Bang for buck, heat pumps will not be beaten on running costs, which is why they make the top of the list. Expect a single room solution to cost between $3,500-$4,500 and central heating to cost between $13,000-$18,000 (subject to make, model and house implications).
Electric Space Heaters
This includes traditional oil column heaters, newer micathermic heaters, fan heaters, convection heaters etc. These are good for bedrooms, if sized correctly. As a low installation cost solution, micathermic heaters are recommended to replace any existing space heaters as they heat rapidly and can keep a small room comfortable easier, plus they are much lighter than your older steel column units. If heating multiple spaces with electric heaters, you will likely experience incredibly high bills at the end of the month, so be cautious.
Wood Burners
Hard to beat sitting around a fire – nice radiant heat and clean burning fireplaces are a favourite choice among many homes. While not as efficient as the previously mentioned sources, fireplaces can throw out huge amounts of heat, which can be moved to bedrooms via heat transfer systems. The major drawback to this solution is the time required to get them going. Wood stoves are a source of indoor and outdoor air pollution, so ensure that an Ultra-Low Emission Burner (ULEB) is chosen and firewood that is burnt has a low moisture content. Estimated cost to install, $5000+.
Flued Gas Heating
Flued gas heating is an effective solution for homes that are already dependent on natural gas for cooking and water heating, as your retailer will likely offer cheaper gas unit pricing. While not as efficient as heat pump driven technology, gas is currently cheaper to run when compared to individual electric heaters. Central heating and individual room options are available, with prices comparable to heat pumps.
Ideally, all new options will be powered from electricity to reduce carbon emissions. The Government’s goal is for New Zealand to have 100% renewable energy by 2050. Gas has a much higher carbon emission rate than electricity as 82% of NZ’s grid is powered by renewable electricity. A Gas Transition Plan will be released by the Government next year, setting out the steps on a long-term pathway to phasing-out fossil gas.
Hot Water Radiators
These are high efficiency, can be powered by heat pumps or by natural gas. Not suited to homes where wall space is at a premium and can be a high installation cost. Major benefits for this solution are independent control for all spaces, a radiant warmth throughout the home and silent operation. Typically $15,000-$25,000 depending on house size and difficulty of installation.
Portable Gas
The only thing to do here is recycle the heater and chuck the gas bottle outside for the barbeque. If used inside it can be very toxic to breathe, generates a significant amount of moisture and is a fire risk.
Gen Less has a handy heating checklist.
3. Moisture mitigation
Many homes in NZ suffer from damp issues, mould development and condensation. A lot of this is down to how we live in our homes, so the following should assist if this sounds familiar.
Heat! Warm homes are dry homes, or at least drier. Cold and damp are synonymous, so the first suggestion is that the home is kept at a reasonable temperature; between 16-18°C at a minimum.
Let the home breathe – windows and doors should be thrown open for at least 10-15 minutes a day, at least once a day. Try to do so at around midday when the air temperature is warmest, if possible. Avoid leaving windows ajar over the course of a winters day, as this allows a constant flow of cold air into the home, making it that much harder to heat.
Ensure bathrooms and kitchens are equipped with suitable extraction systems. Rangehoods should have a surface area larger than the cook top and be directly above, bathroom extractors should be installed directly above the shower as this is where most of the moisture is generated, not central to the room.
If condensation is forming, clear it away immediately, as wet windows can lead to framing deterioration and mould. If you spot mould, clear it off immediately.
Try to avoid drying any washing inside, as this releases huge amounts of moisture into the home (3-5L of moisture per standard load). Also ensure any clothes dryers vent outside, or are self-condensing.
Small measures add up, so it’s recommended that all windows and doors are adequately draught proofed, light bulbs are replaced with low draw LEDs, your hot water pipes are wrapped, and devices/appliances are unplugged or switched right off when not in use.
If you’d like to find out what options best suit your home, please contact us to arrange an assessment with one of our certified Home Performance Advisors who will tailor the advice to your property, requirements and budget.
For more advice about healthy homes get in touch for a free Home Energy Assessment.
For more personalised advice about keeping your home healthy, get in touch for a free Home Energy Assessment.