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Glossary of Building Rating Terms

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NAIMA is the association for North American manufacturers of fiber glass, rock wool, and slag wool insulation products. [Source: NAIMA}


According to the Energy Services Directive Member States shall submit National Energy Efficiency Action Plans (NEEAPs) to the European Commission in which they shall describe the energy efficiency improvement measures planned to reach the indicative energy savings target of 9% set out in the Directive. The second and third NEEAPs, due respectively by 30 June 2011 and 30 June 2014 shall in addition also include a report on progress made towards achieving the Member States’ target. [Source: Concerted Action]

Net Floor Area

A term used in the ISO standard to express the Interior Gross Area less the areas of all interior walls. [Source: BPIE]

Net Zero Energy Buildings

NZEB are buildings that over a year are neutral, meaning that they deliver as much energy to the supply grids as they use from the grids. Seen in these terms they do not need any fossil fuel for heating, cooling, lighting or other energy uses although they sometimes draw energy from the grid. [Source: IEA (Laustsen J.) (2008) Energy Efficiency Requirements in Building Codes, Energy Efficiency Policies for New Buildings.]

Net Zero Energy Cost

In a cost ZEB, the amount of money the utility pays the building owner for the energy the building exports to the grid is at least equal to the amount the pays the utility for the energy services and energy used over the year. [Source: Torcellini et al. 2006]

Net Zero Energy Emission

A net zero emissions building produces at least as much emissions-free renewable energy as it uses from emissions producing energy sources. [Source: Torcellini et al. 2006]

Net Zero Site Energy

A ZEB that produces at least as much on-site energy as it uses in a year, when accounted for the site. [Source: Torcellini et al. 2006]

Net Zero Source Energy

A source of ZEB produces at least as much energy as it uses in a year, when accounted for at the source. Source energy refers to the primary energy used to generate and deliver the energy to the site. To calculate a building's total source energy is multiplied by the appropriate site-to-source conversion multipliers. [Source: Torcellini et al. 2006]

Non-managing building owners

The non-managing building owners are the public or private property developers who build and sell. [Source: IEA Annex 31 Glossary]

Non-Residential Buildings

A building is regarded as a non-residential building when the minor part of the building (i.e. less than half of it's gross floor area) is used for dwelling purposes. Non-residential buildings comprise: Industrial buildings; commercial buildings; educational buildings; health buildings; other buildings. [Source: OECD Glossary of Statistical Terms]


A building that has a very high energy performance as determined in accordance with Annex I. The nearly zero or very low amount of energy required should be covered to a very significant extent by energy from renewable sources, including energy from renewable sources produced on-site or nearby. [Source: EBPD recast, 2010/31/EU]