Are There Any Lessons We Can Take Away From Homeowner Feedback?
- Aug 12, 2025
- 5 min read
Updated: Jun 22
Survey Responses
Ideal Indoor Temperature vs. Thermal Performance of the House
A couple of owners in different parts of the country raised an interesting point about the difference between the temperatures that their homes were generally delivering with minimal heating and cooling, and what they find is their naturally comfortable temperature.
In a home in metropolitan Melbourne, the winter temperature in the morning is usually around 19 degrees (2-3 deg. outside). The owner reports that they are able to feel air being moved by the HRV while sitting near the vents, or a doorway, and that this air is too cool for them to comfortably study or work. They installed a small hydronic heating system with panels in the bedrooms and living areas as part of their build. These owners have found that they need to turn it on to raise the temperature to 22.5 deg., which is what they find is right for them. The sun then warms the house, and the hydronic system switches itself off. The homeowner said that he wasn't expecting to need heating, but that he is happy with the overall performance of his new home. This home achieved 0.59 ACH on blower door test (per the builder).
There is a double height stairwell in my home. On a cold and cloudy day, when the indoor temperature has dropped to around 18 degrees, I can feel cool air moving upstairs from the ground level. This can be a bit uncomfortable if you are lightly dressed and standing at the bottom of the steps. We rely heavily on solar gain to bring our home up to 20-21 degrees during the day, which we find comfortable. In this situation, we use heated towel rails, or RCAC to bump the temperature up a couple of degrees.
In a home in the subtropical Northern Rivers of NSW, daytime summer temperatures are very stable at around 26 degrees. According to the owner, outdoor temperatures are generally around 30 degrees and rarely drop below 20 degrees overnight. Lower temperatures do occur, but this is usually in the early hours of the morning just before daybreak. The internal temperature of this home slowly cycles between 21.3 degrees in winter and 26 degrees in summer. This is a comfortable daytime summer temperature, but it is too warm for sleeping at night. Night purging is not possible because of outdoor humidity and the relatively high outdoor evening temperature. According to the owner, the windows stay "firmly shut" between November and March, and they were made aware that they would need active cooling and dehumidification during summer.
The original design was for a small split system RCAC system in the main living area. However, the owner found that this was not enough to cool the home to a comfortable overnight temperature and achieve humidity control. In attempting to improve this, they installed ceiling fans, increased external shading, made adjustments to the HRV and added an additional small split system RCAC to one side of the home. They were eventually able to achieve their goal of coolth and dehumidification being distributed evenly throughout the home by replacing the cooling with an 8kW multi head split system and 2kW heads in 4 of the rooms. This enables them to cool 2 rooms at a time and rotate cooling through the rooms, thereby achieving a temperature and humidity level that is comfortable for them.
There was a similar comment about the cooling and dehumidification capacity of a home in the Riverina region of NSW, where the homeowner felt it was undersized for the home and their needs to manage the indoor climate while solar power was available. An owner in metropolitan Sydney wrote about realising in hindsight that a ducted air-conditioning system and independent dehumidifier may have been better suited to their project.
In tropical Far North Queensland, an owner says that their 7kW ducted A/C system does a great job of cooling the home, and that they only need it for about 60 days a year. The house is pleasant most of the time, and they only turn it on when the temperature outside rises to about 36 degrees. They are considering a second, small system for one end of the home for visitors and particularly hot days. Humidity is extracted by both the ERV and a dehumidifier. The ERV manages occupants' showers and low humidity days. However, once the humidity gets above 55%, the dehumidifier will automatically kick in. On high humidity days when it is raining and above 80%, it can pull as much as 30 litres of water out of the house per day! The region has high humidity for about 80% of the year.
In a Climate Zone Where Cooling is Important, it's a Good Idea to Give Some Thought to Awnings and Blinds Early in the Design Process
There are just so many decisions to make along the way when you are building a new home. It can be difficult to gauge how much thought is required to get each one right (or nearly right!). Even if your home has good insulation, air-tightness and high-performance glazing, attention needs to be focussed on shading in the hotter months. A couple of homeowners have indicated that their homes were too hot in the warmer months after they had initially moved in. Because there were so many priorities competing for their time and funds, these homeowners left installing blinds and awnings until after they had moved in.
It is worthwhile having a conversation with your architect and builder about options during the design and window selection stage. This will help to ensure that elements of the design, say skillion roof slope or orientation, or the size of a large glazed areas, don't prevent a future external shading option. It's is not all bad news if this has not been possible. I have been very happy with the internal blinds on my north and west facing windows. They are foil-backed honeycomb blinds and have been very effective in keeping the heat out.
Less White Noise From Outside the House, Means You Hear More White Noise From the House
Heat Recovery Ventilation Systems and Energy Recovery Ventilation Systems are still relatively uncommon in houses in Australia. We are only beginning to get used to them. These systems do make some noise, and this is audible in a very quiet home.
A couple of homeowners commented about the background hum that is usually audible in the living areas and bathrooms. This is particularly true when the HRV/ERV is in boost mode for increased extraction during showers and cooking etc. Sound is also emitted at the other end of the system, where the heat or energy exchange core and fan are located. The general advice is to install the unit away from living areas, in a laundry or storage area. A homeowner commented that they would put this unit into its own cabinet, if they were doing it again.
These systems move air around the home, but it is a very gentle movement, and this was an issue for a couple of homeowners. In a home with high ceilings and cathedral ceilings, the owner reported feeling that the flow was not adequate. Another felt that there was not enough airflow in their childrens' bedrooms in summer, meaning that they needed to sleep with bedroom doors open. And like me, 1 homeowner thought that the HRV would move enough air in and out of the bedrooms to distribute conditioned air for an even temperature in all rooms. Like me, this homeowner had to retrofit ceiling fans to help, which has fixed the problem. I'll say it, a pretty easy trap to fall into!
Disclaimer: These are the opinions of homeowners. These homes are high-performance, energy-efficient homes. Some of them are PHI certified and some are not. The uncertified homes were never intended for certification and the performance described above is unrelated to certification of these homes. All homeowners are happy with the overall performance their homes. See the full disclaimer in the footer of this website for further information.
