4 Design Standard for New Woodburners
4.1 Background
In most urban areas in New Zealand the main source of fine particle emissions is solid fuel burning in home heating appliances. The introduction of the new woodburner design standard is therefore expected to result in reductions in fine particle concentrations and associated health impacts.
While the new woodburner standard only limits emissions of particulates, it has the additional benefit of controlling the emissions of other harmful pollutants such as carbon monoxide, volatile organic compounds, polycyclic aromatic hydrocarbons, toxics and dioxins.
This section outlines the woodburner standard (section 4.2) including what it does, and does not, apply to.
4.2 What is the woodburner design standard?
Regulations 23 and 24 require the following:
23 Design standard
(1) The design standard for a woodburner is a discharge of less than 1.5 gram of particles for each kilogram of dry wood burnt.
(2) The discharge must be measured in accordance with the method specified in the Australian/New Zealand Standard AS/NZ 4013:1999, Domestic solid fuel burning appliances - Method for determination of flue gas emissions.
24 Thermal efficiency standard
(1) The thermal efficiency standard for a woodburner -
(a) is the ratio of useable heat energy output to energy input (thermal efficiency); and
(b) must be not less than 65%.
(2) The thermal efficiency must be calculated in accordance with the method specified in Australian/New Zealand Standard AS/NZ 4012:1999, Domestic solid fuel burning appliances - Method for determination of power output and efficiency.
The standard specifies a maximum particle emission limit of 1.5 g/kg of wood burnt as measured in accordance with AS/NZS 4013:1999. This method specifies a test procedure for determining the rate of particulate emission from batch feed solid fuel burning appliances.
The standard further specifies a minimum thermal efficiency of 65 percent as measured in accordance with AS/NZS 4012:1999. This method specifies a test procedure for the determination of the average efficiency and average thermal power output from batch feed domestic solid fuel burning appliances.
4.2.1 What does it apply to?
Under the regulations a woodburner is defined as:
(a) a domestic heating appliance that burns wood; but
(b) does not include -
i. an open fire; or
ii. a multifuel heater, a pellet heater, or a coal burning heater; or
iii. a stove that is -
(A) designed and used for cooking; and
(B) heated by burning wood.
4.2.2 Where does it apply?
Regulation 22 states that the standard applies to woodburners installed in certain properties:
22 Discharge from woodburners installed in certain properties after 1 September 2005 prohibited
(1) The discharge of particles to air from a woodburner installed after 1 September 2005 in a building or property with an allotment size of less than 2 hectares is prohibited.
(2) Subclause (1) does not apply if the discharge from the woodburner complies with -
(a) the design standard in regulation 23; and
(b) the thermal efficiency standard in regulation 24.
The woodburner standard applies to all new woodburners installed in urban areas in New Zealand after 1 September 2005. For the purpose of this standard an urban area is defined as a property with a lot size of 2 ha or less (20,000 m2). Information on the size of a lot is available from the property title or Land Information Memoranda (LIM) report.
The standard does not apply to existing woodburners - unless they are reinstalled into a property.
People will still be able to operate or install open fires, multi-fuel burners, pellet fires, and wood/coal stoves designed for the primary purpose of cooking, and coal burners, unless their regional plan prevents this.
4.2.3 Who does it affect?
The woodburner design standard affects anyone installing a woodburner in a building or property with a lot size of less than 2 hectares. It does not affect people installing open fires, cooking ranges, coal burners, pellet heaters or multi fuel burners.
It further affects home heating manufacturers, retailers and territorial authorities, who sell, install and/or grant building consents for the installation of woodburners.
4.3 Implementation
From 1 September 2005, all woodburners installed into a house or dwelling, on a lot size less than 2 hectares, must meet the design (emissions) and thermal efficiency standards outlined above. This includes reconditioned and/or second-hand woodburners.
It should be noted that the woodburner standard refers to the installation of woodburners. Non-complying woodburners can still be sold but they may then only be installed in homes on a property with a lot size of over 2 hectares.
There are a wide range of woodburners on the market which meet the standard. Two lists of woodburner models which have been tested and found to meet the performance requirements of the standard at the date of testing are provided on the Ministry for the Environment's website. The first list includes models that have been tested and authorised by Environment Canterbury. The second list includes models that have certificates stating that they have been tested and meet the standard. Please note that the woodburner models on the second list have not been authorised by any agency. You should refer to the Ministry's website for further information: www.mfe.govt.nz/
It should be noted that both lists have not been independently verified and the woodburner models listed are not, at this stage, subject to regular audits to ensure continued compliance. As a consequence, the Ministry is unable to warrant that any particular woodburner of the models tested meets the standards. The Ministry does not accept any liability arising from the lists and will not pay compensation to anyone relying on these lists in the event a woodburner is found to be non-complying and has to be removed. The Ministry encourages retailers to make purchasers aware of these caveats.
Further, it should be noted that whilst the lists are updated periodically, they are not an exhaustive list of all compliant models that may be available at any given time.
4.4 What is the impact on regional plans?
The standards are mandatory regulations introduced through sections 43 and 44 of the RMA. They automatically supersede any relevant regional plan rules - unless the local government controls are stricter.
There is nothing in the standards that directly affects rules in plans. However, section 43B (the 'stricter provision prevails rule') overrides any rule which attempts to set a more lenient standard. The rule will be trumped whether it is in effect before the standard comes into force. There is no protection for more lenient rules in existence at the time the standards come into force.
Therefore, there is no need for regional councils to initiate a review of their regional plan to bring them in compliance with the national environmental standards - the standards apply automatically. The Ministry recommends the use of clerical annotations to regional plans to inform readers that the relevant sections have been superseded by the national environmental standards. This would remove confusion and make the requirements of the woodburner standard clear to the public.
4.5 Role of territorial authorities
Compliance with the proposed woodburner standard is the responsibility of the regional councils. However, in practice, the role of the territorial authorities is paramount.
New woodburner installations require a building consent from their territorial authority to ensure they meet Building Code requirements (eg, safety and structural integrity). The national environmental standards are regulations made under the Resource Management Act 1991 and there may not be a link to the Building Act 2004. It would be prudent however, for territorial authorities to inform the home owner that granting of a building consent is not authority to install and operate a non-complying woodburner.
It is suggested that territorial authorities issue an advice note with a building consent for woodburners alerting the owner to the air quality regulations, as these regulations prevent discharge from any non-complying woodburner.
It is further suggested that regional councils liaise with the relevant territorial authorities, as they are responsible for enforcement of the regulations. Territorial authorities may however, want to consult their own lawyers as to whether there is a link between the two statutes in relation to woodburners.
To help territorial authorities understand the national environmental standards and their role in the woodburner design standard, the Ministry held a series of meetings throughout March - May 2005. A total of 49 territorial authorities attended these meetings. Subsequently the Ministry wrote to all territorial authorities informing them of the above and provided brochures for members of the public.
Information on models that comply with the woodburner standard is available on the Ministry for the Environment's website.
NB: It should be noted that the woodburner design standard only applies to properties less than 2 hectares and is not retrospective. If a property size is reduced (eg, via subdivision) after the standard comes into force to less than two hectares, the standard will not apply retrospectively - any existing woodburner can remain.
4.6 Enforcement
Any person who discharges particles from a woodburner which does not comply with the standard could be subject to enforcement action from the regional council in accordance with the enforcement provisions of the RMA.
4.7 Education
Retailers will be able to sell woodburners with a design standard of greater than 1.5 g/kg, and with a thermal efficiency of less than 65 percent, but only for the installation in properties greater than two hectares. Under the Consumer Guarantees Act, retailers should make the implications of the woodburner standard clear to their customers at the time of sale.
