28 Hamilton

• Bader

• Beerescourt

• Bryant

• Brymer

• Chartwell

• Chedworth

• Clarkin

• Claudelands

• Dinsdale North

• Dinsdale South

• Enderley

• Fairview Downs

• Flagstaff

• Frankton Junction

• Glenview

• Hamilton Central

• Hamilton East

• Hamilton Lake

• Horsham Downes

• Hillcrest West

• Huntington

• Insoll

• Maeroa

• Melville

• Nawton

• Naylor

• Peachgrove

• Porritt

• Pukete

• Pukete West

• Queenwood

• Riverlea

• Rototuna

• Rotokauri

• Silverdale

• Swarbrick

• Te Rapa

• University

Survey details are shown in Table 28.1. The number of households for 2004 was estimated based on 2001 census data for occupied dwellings, extrapolated for 2004 based on Statistics New Zealand population projections. [New Zealand Statistics 2004, www.stats.govt.nz] The latter suggest a population increase for Hamilton City of 26% by 2021. [High, medium and low population projections were estimated by Statistics New Zealand. The value used is the medium population projection.]

Table 28.1: Summary survey data, Hamilton

28.1 Home heating methods and fuels

The Digipoll survey was used to collect information on home heating methods and fuels for Hamilton. These data were collected for the purpose of evaluating the impact of variations in heating methods on air quality in Hamilton, in particular the extent of change required to achieve the national environmental standard for PM10. This section presents the results of the home heating survey for Hamilton largely in tabular form, in the expectation that these results will be of value in other assessments (eg, emission inventory studies).

Tables 28.2 and 28.3 show domestic heating methods and fuels used for the main living areas in Hamilton houses, and seasonal variations in heating behaviour. The commonest methods of heating the main living area in Hamilton were gas (64%) and electricity (26%). Many households used more than one method of heating in their main living area.

Table 28.2: Domestic home heating methods and fuels, Hamilton

Around 5% of households that use wood burners heat their houses during the months of January and February (Table 28.3). The quantities of fuel used per day during non-winter months were typically less than during the winter (Table 28.4). Data are not presented for all heating methods because there was a high non-response rate for questions relating to seasonal variations for some heating types.

Table 28.3: Monthly variations in heating behaviour and fuel use, Hamilton

Table 28.4: Estimated daily fuel use, by season, Hamilton

28.2 Insulation, cost of heating, income, and house age and size

In addition to collecting data for the purpose of evaluating the impact of variations in heating methods on air quality, information was collected on a number of variables relevant to the Ministry for the Environment's Warm Homes Project. Relevant data for Hamilton are presented in this section.

Figure 28.1 shows that the proportion of households using gas systems that are properly flued in Hamilton is around 43%. This compares to a national average of 24%.

The amount spent on heating for a winter month, by heating method, is shown in Table 28.5. In Hamilton, households heating using wood burners spent less per month on average (around $55) than those using other heating methods.

Figure 28.2 shows the average heating costs, home ownership, age of dwelling and number of bedrooms for households in Hamilton. Around 28% of the respondents in Hamilton were living in rental accommodation. This compares with a national average of around 20%.

One factor influencing the amount spent on different heating methods is the ability of households using solid fuel burners to obtain wood free of charge. Figure 28.3 shows that around 60% of the wood used on wood burners and multi-fuel burners in Hamilton is purchased.

Figure 28.1: Distribution of flued versus unflued gas heating and age of wood burner, Hamilton

Text description of figure

There are two pie graphs. The first graph shows the distribution of flued and unflued gas heaters. Unflued gas makes up 43% of all gas heating and Flued gas makes up 57%.

The second graph is divided by the age of wood burners. Post-1999 wood burners make up 16%, 1994-99 wood burners make up 21% and the remaining 63% of wood burners are Pre-1994.

Table 28.5: Average monthly heating costs (winter), Hamilton

Figure 28.2: Domestic heating method, by average monthly heating expenditure, house ownership, house age and number of bedrooms, Hamilton

Average heating cost per month (winter)

House ownership

Age of dwelling

Number of bedrooms

Text description of figure

The first graph sets out the average heating cost per month in winter. Cost per month by heating methods are: electric $72, gas $88, open fire $0, wood burner $55, pellet burner $0, multi-fuel $71 and oil $0.

The second graph sets out heating methods divided by home tenure. For households living in rentals 2504 use electric, 6398 use gas, 556 use open fire, 1669 use wood burners, 0 use pellet burners, 0 use multi-fuel and 0 use oil. For households living in their own house 8624 use electricity, 20586 use gas, 556 use open fires, 4173 use wood burners, 0 use pellet burners, 1391 use multi-fuel and 0 use oil.

The third graph sets out the age of a dwelling using a particular method of heating.

• Heating methods for houses under 10 years old are 28% electric, 25% gas, 24% wood burners, 60% multi fuel and 25% open fires.
• Heating methods for houses between 11 and 20 years old are 18% electric, 16% gas, 24% wood burners, 0% multi fuel and 0% open fires.
• Heating methods for houses between 21 and 40 years old are 20% electric, 26% gas, 5% wood burners, 0% multi fuel and 25% open fires.
• Heating methods for houses over 41 years old are 25% electric, 26% gas, 43% wood burners, 40% multi fuel and 25% open fires.

The fourth graph sets out particular heating methods by the number of bedrooms.

• Heating methods for houses with one bedroom are 0% electricity, 0% gas, 0% wood burner, 0% multi fuel and 0% open fire.
• Heating methods for houses with two bedrooms are 30% electricity, 12% gas, 0% wood burner, 0% multi fuel and 25% open fire.
• Heating methods for houses with three bedrooms are 38% electricity, 56% gas, 38% wood burner, 60% multi fuel and 50% open fire.
• Heating methods for houses with four bedrooms are 25% electricity, 23% gas, 38% wood burner, 20% multi fuel and 25% open fire.
• Heating methods for houses with five bedrooms are 5% electricity, 6% gas, 19% wood burner, 20% multi fuel and 0% open fire.
• Heating methods for houses with six bedrooms are 3% electricity, 2% gas, 5% wood burner, 0% multi fuel and 0% open fire.

Figure 28.3: Proportions of fuel obtained free of charge versus bought, Hamilton

Text description of figure

This bar graph shows the amount of wood either bought or collected free of charge by three different types of heating.

Those using open fires bought 50% of their fuel, those using wood burners bought 69% of their fuel and those using multi-fuel burners bought 62% of their fuel.

Table 28.6: Type of electric heating, Hamilton

The commonest types of electric heating used in the main living area in Hamilton houses were oil column heaters, fan heaters and radiant heaters (Table 28.6). A number of houses used more than one type of electric heater in their main living area.

Data on home heating methods, by house ownership, are shown in Table 28.7.

Table 28.7: Home heating method, by house ownership, Hamilton

Household insulation types and heating methods are shown in Tables 28.8 and 28.9. Around 75% of houses had ceiling insulation and around 55% had wall insulation. Around 8% of houses had at least four types of insulation.

Table 28.10 shows home heating method, by household income. The overall non-response rate was around 26%. This limits the interpretation of these data because there may be an income bias in the non-respondents.

Table 28.8: House insulation summary statistics, Hamilton

Table 28.9: Degree of house insulation, by heating method, Hamilton

Table 28.10: Home heating method, by household income, Hamilton

Tables 28.11 and 28.12 show the relationship between heating methods and the age of the dwelling and number of bedrooms, respectively.

Table 28.11: Home heating method, by age of dwelling, Hamilton

Table 28.12: Home heating method, by number of bedrooms, Hamilton