21 Timaru

Survey details are shown in Table 21.1. 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 decrease for Timaru of 7% by 2021. [High, medium and low population projections were estimated by Statistics New Zealand. The value used is the medium population projection.]

Table 21.1: Summary survey data, Timaru

21.1 Home heating methods and fuels

The Digipoll survey was used to collect information on home heating methods and fuels for Timaru. These data were collected for the purpose of evaluating the impact of variations in heating methods on air quality in Timaru, 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 Timaru largely in tabular form, in the expectation that these results will be of value in other assessments (eg, emission inventory studies).

Tables 21.2 and 21.3 show domestic heating methods and fuels used for the main living areas in Timaru houses, and seasonal variations in heating behaviour. The commonest methods of heating the main living area in Timaru were electricity (59%) and wood burners (44%). Many households used more than one method of heating in their main living area.

Table 21.2: Domestic home heating methods and fuels, Timaru

Only a small proportion of households using solid fuel burning use their burners to heat their homes during the summer months (Table 21.3). Those that do burn during the summer months typically use less fuel per day than the average during winter (Table 21.4). 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 21.3: Monthly variations in heating behaviour and fuel use, Timaru

Table 21.4: Estimated daily fuel use, by season, Timaru

21.2 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 Timaru are presented in this section.

Figure 21.1 shows that the proportion of households using gas systems that are properly flued in Timaru is around 40%. This compares to a national average of 24%.

The amount spent on heating for a winter month, by heating method, is shown in Table 21.5. In Timaru, households heating using open fires spent on average more per month (around $130) than those using other heating methods.

Figure 21.2 shows the average heating costs, home ownership, age of dwelling and number of bedrooms for households in Timaru. Only a small proportion (16%) of the respondents in Timaru 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 21.3 shows that over 70% of the wood used on solid fuel burners in Timaru is self-collected.

Figure 21.1: Distribution of flued versus unflued gas heating and age of wood burner, Timaru

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 60% of all gas heating and Flued gas makes up 40%.

The second graph is divided by the age of wood burners. Post-1999 wood burners make up 30%, 1994-99 wood burners make up 38% and the remaining 32% of wood burner are Pre-1994.

 

Table 21.5: Average monthly heating costs (winter), Timaru

Figure 21.2: Domestic heating method, by average monthly heating expenditure, house ownership, house age and number of bedrooms, Timaru

Average heating cost per month (winter)

House ownership

Age of dwelling

Number of bedrooms

Text description of figure

There are four bar graphs.

The first graph sets out the average heating cost per month in winter. Cost per month by heating methods are: electric $77, gas $69, open fire $130, wood burner $102, pellet burner $0, multi-fuel $64 and oil $86.

The second graph sets out heating methods divided by home tenure. For households living in rentals 948 use electric, 406 use gas, 338 use open fire, 541 use wood burners, 0 use pellet burners, 135 use multi-fuel and 0 use oil. For households living in their own house 5076 use electricity, 2098 use gas, 406 use open fires, 3926 use wood burners, 0 use pellet burners, 948 use multi-fuel and 203 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 2% electric, 3% gas, 2% wood burners, 0% multi fuel and 0% open fires.
• Heating methods for houses between 11 and 20 years old are 3% electric, 3% gas, 5% wood burners, 6% multi fuel and 0% open fires.
• Heating methods for houses between 21 and 40 years old are 36% electric, 24% gas, 20% wood burners, 31% multi fuel and 36% open fires.
• Heating methods for houses over 41 years old are 54% electric, 62% gas, 68% wood burners, 63% multi fuel and 55% open fires.

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

• Heating methods for houses with one bedroom are 3% electricity, 3% gas, 0% wood burner, 0% multi fuel and 9% open fire.
• Heating methods for houses with two bedrooms are 28% electricity, 19% gas, 9% wood burner, 0% multi fuel and 0% open fire.
• Heating methods for houses with three bedrooms are 48% electricity, 51% gas, 59% wood burner, 88% multi fuel and 73% open fire.
• Heating methods for houses with four bedrooms are 18% electricity, 22% gas, 27% wood burner, 13% multi fuel and 18% open fire.
• Heating methods for houses with five bedrooms are 1% electricity, 5% gas, 3% wood burner, 0% multi fuel and 0% open fire.
• Heating methods for houses with six bedrooms are 0% electricity, 0% gas, 0% wood burner, 0% multi fuel and 0% open fire.

Figure 21.3: Proportions of fuel obtained free of charge versus bought, Timaru

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 28% of their fuel, those using wood burners bought 28% of their fuel and those using multi-fuel burners bought 30% of their fuel.

Table 21.6: Type of electric heating, Timaru

The commonest types of electric heating used in the main living area in Timaru houses were heat pumps and fan heaters (Table 21.6). 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 21.7.

Table 21.7: Home heating method, by house ownership, Timaru

Household insulation types and heating methods are shown in Tables 21.8 and 21.9. Just under 80% of households had ceiling insulation and 44% had wall insulation. Only 25% of houses had at least three types of insulation.

Table 21.10 shows home heating, method by household income. The overall non-response rate was around 27%. This limits the interpretation of these data because there may be an income bias in the non-respondents.

Table 21.8: House insulation summary statistics, Timaru

Table 21.9: Degree of house insulation, by heating method, Timaru

Table 21.10: Home heating method, by household income, Timaru

Tables 21.11 and 21.12 show the relationship between heating methods and the age of the dwelling and number of bedrooms, respectively.

Table 21.11: Home heating method, by age of dwelling, Timaru

Table 21.12: Home heating method, by number of bedrooms, Timaru