Variable Description
Main types of heating used
The main types of heating used measures the types of heating that are usually used to heat an occupied private dwelling. It indicates the appliances used, and, in most cases, the fuels used (eg heat pump, fixed gas heater, wood burner). Any types of heating that are only used very rarely or are available but not used are excluded. Insulation is not a heating type.
Fuel types used to heat dwellings
The 2018 Census data on fuel types used to heat dwellings measures the main types of fuels used to heat an occupied private dwelling. Main fuel types used refers to those used most often, not every single type used in an occupied private dwelling. More than one main fuel type may be used; for example, electricity, gas, coal, and wood. Insulation is not a fuel type.
Notes on interpretation
Main types used means those that the respondent has used most often during periods when heating was required - the type or types they generally rely on. Any forms of heating that a respondent uses relatively rarely compared with others are excluded. Also excluded are any heating types available in the dwelling that are not used at all or are disconnected or broken.
The heating types data does not indicate how many heating appliances of each type were used in a dwelling eg it does not indicate the number of heat pumps used, or whether one electric heater or multiple electric heaters were used. Each type of heating reported was recorded once only.
- Main types of heating used (total response data)
- Main types of heating used – single/combination
- Number of heating types used
- Fuel types used in dwellings (total response data)
- Number of heating fuels used
Main types of heating used is a new form of heating information that has been introduced for the 2018 Census.
The heating information collected previously was all fuel types that had ever been used.
Priority level
Priority level 3
We assign a priority level to all census variables: Priority 1, 2, or 3 (with 1 being highest and 3 being the lowest priority).
Main types of heating used is a priority 3 variable. Priority 3 variables do not fit in directly with the main purpose of a census but are still important to certain groups. These variables are given third priority in terms of quality, time, and resources across all phases of a census.
The census priority level for this variable remains the same as for the 2013 Census data on fuel types used in dwellings.
Quality Management Strategy and the Information by variable for Fuel type used to heat dwelling (2013) have more information on the priority rating.
Overall quality rating for 2018 Census
Moderate quality
Data quality processes section below has more detail on the rating for this variable.
The External Data Quality Panel has provided an independent assessment of the quality of this variable and have rated it as moderate quality. 2018 Census External Data Quality Panel: Assessment of Variables has more information.
Subject population
Occupied private dwellings
‘Subject population’ means the people, families, households, or dwellings to whom the variable applies.
How this data is classified
Census main types of heating used V2.0.0
Main types of heating used is a flat classification with the following categories:
0 No heating used
1 Heat pump
2 Electric heater
3 Fixed gas heater
4 Portable gas heater
5 Wood burner
6 Pellet fire
7 Coal burner
8 Other types of heating
9 Not elsewhere included
This is a new classification for the 2018 Census.
‘Not elsewhere included’ contains the residual categories of ‘response unidentifiable’ and ‘response outside scope’ alongside ‘not stated’.
Census number of heating types used V2.0.0
Number of heating types used is a flat classification with the following categories:
0 No heating types used
1 One heating type used
2 Two heating types used
3 Three heating types used
4 Four heating types used
5 Five heating types used
6 Six heating types used
7 Seven heating types used
8 Eight or more heating types used
9 Not elsewhere included
This is a new classification for the 2018 Census
‘Not elsewhere included’ contains the residual categories of ‘response unidentifiable’ alongside ‘not stated’.
Census main types of heating used – single/combination V2.1.0
Main types of heating used – single/combination is a flat classification with the following categories:
000 No heating used
011 Heat pump only
012 Electric heater only
013 Fixed gas heater only
014 Portable gas heater only
015 Wood burner only
016 Pellet fire only
017 Coal burner only
018 Other main type of heating only
021 Heat pump and electric heater
022 Heat pump and fixed gas heater
023 Heat pump and wood burner
024 Electric heater and fixed gas heater
025 Electric heater and portable gas heater
026 Electric heater and wood burner
029 Other combinations of two main types
031 Heat pump, electric heater, and wood burner
039 Other combinations of three or more main types
999 Not elsewhere included
This is a new classification for the 2018 Census.
Census main types of heating used is a multiple response variable. Therefore the total number of responses in a table is greater than the total occupied private dwellings stated.
‘Not elsewhere included’ contains the residual categories of ‘response unidentifiable’ alongside ‘not stated’.
Census fuel types used in dwellings V2.0.0
Fuel types used in dwellings is a flat classification with the following categories:
011 Electricity
012 Gas
013 Wood
014 Coal
015 Home heating oil
016 Solar power
017 No fuels used in this dwelling
018 Other fuel(s)
999 Not elsewhere included
This classification has changed since 2013. Previously there were separate categories for mains gas and bottled gas. These categories have been combined because the information collected in 2018 no longer clearly distinguishes whether gas is mains or bottled.
‘Not elsewhere included’ contains the residual categories of ‘response unidentifiable’ and ‘response outside scope’ alongside ‘not stated’.
Census number of heating fuels used V2.0.0
Number of heating fuels used is a flat classification with the following categories:
0 No heating fuels used
1 One fuel
2 Two fuels
3 Three fuels
4 Four fuels
5 Five fuels
6 Six fuels
7 Seven or more fuels
9 Not elsewhere included
This classification is the same as that used in the 2013 and 2006 Censuses.
‘Not elsewhere included’ contains the residual categories of ‘response unidentifiable’ alongside ‘not stated’.
Information by variable for Fuel type used to heat dwelling (2013) has more information).
The Standards and Classifications page provides background information on classifications and standards.
Question format
Main types of heating used is collected on the dwelling form (question 11 on the paper form).
Stats NZ Store House has samples for both the individual and dwelling paper forms.
The question and response categories for main types of heating have changed since 2013 due to the change in the type of information collected.
There were no differences between the wording or question format in the online and paper versions of this question but there were differences in the way a person could respond.
On the online dwelling form:
- previous responses disappeared if ‘don’t use any form of heating’ was ticked
- for the category ‘other (heating type)’, an as-you-type auto-suggestion list appeared once the respondent started typing in the box for example if the respondent typed in wood, suggestions of ‘wood pellet fire’ and ‘wood burner’ appeared
- the ‘other’ text field only became visible when ‘other’ was selected.
On the paper dwelling form:
- it was possible to give an inconsistent multiple response ie mark boxes indicating heating types used and mark ‘don’t use any form of heating’. These responses were resolved by edits.
How this data is used
Outside Stats NZ
- To support monitoring requirements against the National Environmental Standards for Air Quality and regional air quality plans.
- For modelling particulate emissions and understanding how emission trends may be affected by changes in heating technology use.
- To track heating use against clear air heating legislation, monitor the effectiveness of energy and carbon-reduction policies and inform air quality policies.
- To identify areas affected by fuel poverty.
- For tracking health outcomes and risk factors for respiratory and cardiovascular diseases.
- In community profiles produced to help with community development work.
- For understanding changes in energy demands.
- To assist in dealing with fire incidents – it helps ensure firefighter safety (by identifying areas where many dwellings have gas heating) and with targeting responses to fires (by identifying areas with lots of firewood or easily combustible fuel available).
- To inform civil defence and emergency management planning.
- To provide denominators that sit alongside information from other sources about social conditions.
Within Stats NZ
- In in-depth reports such as ‘Housing in Auckland’.
2018 data sources
No alternative data source or imputation was used to replace missing responses or responses that could not be classified for main types of heating used.
| 2018 main types of heating – occupied private dwellings | |
|---|---|
| Source | Percent |
| Response from 2018 Census | 92.3 percent |
| 2013 Census data | 0.0 percent |
| Administrative data | 0.0 percent |
| Statistical imputation | 0.0 percent |
| No information | 7.7 percent |
| Total | 100 percent |
| Due to rounding, individual figures may not always sum to the stated total(s) |
| 2018 fuel types used to heat dwellings – occupied private dwellings | |
|---|---|
| Source | Percent |
| Response from 2018 Census | 92.3 percent |
| 2013 Census data | 0.0 percent |
| Administrative data | 0.0 percent |
| Statistical imputation | 0.0 percent |
| No information | 7.7 percent |
| Total | 100 percent |
| Due to rounding, individual figures may not always sum to the stated total(s) |
The ‘no information’ percentage is where we were not able to source main types of heating used data for a dwelling in the subject population.
Missing and residual responses
‘No information’ in the data sources table is the percentage of the subject population coded to ‘not stated’. In recent previous censuses, non-response was the percentage of the subject population coded to ‘not stated.’
Percentage of ‘not stated’ for occupied private dwellings
Main types of heating
- 2018: 7.7 percent.
Fuel types used to heat dwellings
- 2018: 7.7 percent
- 2013: 5.1 percent
- 2006: 3.9 percent.
Responses that could not be classified or did not provide the type of information asked for (response unidentifiable, response outside scope) remain in the data, where we have been unable to find information from another source. In the data sources table, these residual categories are included in the ‘Response from 2018 Census’ percentage.
For output purposes, these residual categories are grouped with ‘not stated’ and are classified as ‘not elsewhere included’.
Percentage of ‘not elsewhere included’ for occupied private dwellings
Main types of heating
- 2018: 8.8 percent.
Fuel types used to heat dwellings
- 2018: 9.3 percent
- 2013: 5.5 percent
- 2006: 4.5 percent.
2013 Census data user guide provides more information about non-response in the 2013 Census.
Data quality processes
Overall quality rating: Moderate quality
Data was evaluated to assess whether it meets quality standards and is suitable for use.
Three quality metrics contributed to the overall quality rating:
- data sources and coverage
- consistency and coherence
- data quality.
The lowest rated metric determines the overall quality rating.
Data quality assurance for 2018 Census provides more information on the quality rating scale.
Data sources and coverage:
Heating type variables: Moderate quality
Fuel type variables: Moderate quality
We have assessed the quality of all the data sources that contribute to the output for the variable. As no alternative data sources or imputation were used to replace missing responses, the final data sources and coverage quality rating for heating type and fuel type variables reflects the lower than expected response to the census overall and the high proportion of admin enumeration.
The rating for a valid census response is defined as 1.00. Ratings for other sources are the best estimates available of their quality relative to a census response. Each source that contributes to the output for that variable is then multiplied by the proportion it contributes to the total output. The total score then determines the metric rating according to the following range:
- 98–100 = very high
- 95–<98 = high
- 90–<95 = moderate
- 75–<90 = poor
- <75 = very poor.
The proportion of data from received forms therefore contributed to the score of 0.92, determining the moderate quality rating.
| Quality rating calculation table for the sources of main types of heating data – 2018 occupied private dwellings |
|||
|---|---|---|---|
| Source | Rating | Percent of total | Score contribution |
| 2018 Census form | 1.00 | 92.25 | 0.92 |
| No Information | 0.00 | 7.75 | 0.00 |
| Total | 100.00 | 0.92 | |
| Due to rounding, individual figures may not always sum to the stated total(s) or score contributions. |
| Quality rating calculation table for the sources of fuel types used to heat dwellings data – 2018 occupied private dwellings |
|||
|---|---|---|---|
| Source | Rating | Percent of total | Score contribution |
| 2018 Census form | 1.00 | 92.25 | 0.92 |
| No Information | 0.00 | 7.75 | 0.00 |
| Total | 100.00 | 0.92 | |
| Due to rounding, individual figures may not always sum to the stated total(s) or score contributions. |
Consistency and coherence:
Heating type variables: High quality
Fuel type variables: Moderate quality
As the heating type variables are new, there is no available census data for comparison with 2013 and 2006. However, the data generally meets expectations based on the previous data on fuels and other information on use of heating appliances. There was some minor variation from expectations due to the lower than expected response to the census overall.
The fuel types data is mostly consistent with expectations across consistency checks. There is an overall difference in the data compared with expectations and benchmarks that can be explained by the lower than expected response to the census overall.
- The small decline in electricity use is thought to be due to an increased amount of data in residual categories, particularly ‘not stated’, rather than real-world change.
Data quality:
Heating type variables: High quality
Fuel type variables: Moderate quality
The data quality checks for heating included edits for consistency within the dataset and cross-tabulations to regional council level.
For the heating type variables, the data has only minor data quality issues. The quality of coding and responses within classification categories is high. The percentage of responses coded as ‘response unidentifiable’ was low.
For the fuel types data, the quality of coding and responses within classification categories was moderate. As fuels data was not collected directly in 2018, the data quality is not as high as in previous censuses.
In 2018 text responses such as ‘none’ or ‘no heating’ were coded to ‘No heating used’, which had not happened previously. This is likely to have increased the number of dwellings where no heating is used compared with previous censuses.
Recommendations for use and further information
The overall quality of the main types of heating used data is moderate.
As the heating type variables are new there is no comparability with 2013 and 2006. Time series analysis can be done for fuels used but the 2018 fuels data is not fully comparable with the previous fuels data. This is due to the change in concept from all types ever used to main types used only and the increase in data in residual categories for 2018.
When using this data you should be aware that:
- data has been checked to regional council level. Some variation is possible at geographies below this level
- the increased non-response for 2018 means that this data may not always fully reflect real-world heating use or trends
- the heating information collected in the census has been changed in response to users’ needs. Submissions on content for the 2018 Census indicated the importance of collecting information on heating appliances used. The information collected previously (all fuel types ever used) did not provide a clear enough picture of heating use
- for time series analysis on gas use, the mains gas and bottled gas categories in the previous data can be combined and compared with the gas category in the 2018 data
- the number of dwellings where no heating is used compared with previous censuses is likely to have increased in 2018 due to text responses such as ‘none’ or ‘no heating’ being coded to ‘No heating used’, which had not happened previously
- responses for around 1 percent of all private occupied dwellings provided one or more valid types of heating as well as a response that was categorised as ‘response unidentifiable’ or ‘response outside scope’. Only the valid type of heating should have been retained for these dwellings. Instead, both the valid and unidentifiable and outside scope responses were retained, which has inflated the counts for unidentifiable and outside scope responses and the ‘Not elsewhere included’ (NEI) category. NEI for these variables is the sum across dwellings with responses unidentifiable or outside scope or ‘not stated’ or a combination of response unidentifiable and outside scope. This issue does not affect counts for the valid responses or for the total stated count. The table below shows for each of main types of heating and fuel type variables in the 2018 Census, the percentage of dwellings which had both a valid response and unidentifiable and/or outside scope response.
| Percentage of private occupied dwellings which had both a valid response and unidentifiable and/or outside scope response for 2018 main types of heating and fuel types used to heat dwellings | ||
|---|---|---|
| Main types of heating | Fuel types used to heat dwellings | |
| 77 Response unidentifiable | 0.30 | 0.64 |
| 88 Response outside scope | 0.38 | 0.38 |
| 77 and 88 combined | 0.01 | 0.01 |
| 99 Not stated | 0.01 | 0.01 |
| Not elsewhere included | 0.69 | 1.03 |
| A very small number of dwellings were coded to 99 'not stated' together with one of more valid responses |
Contact our Information Centre for further information about using this variable.
