Frequently Asked Questions
Use the below headings to navigate to a specific section. These are frequently asked questions, answered by the Standard's Technical Steering Group.
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Definitions
1
What do you mean by a "Net Zero Carbon Aligned Building"?
A building whose operational and embodied carbon performance is within limits which allow the UK built environment to stay within its own allocation of remaining carbon budget, in order to limit warming to 1.5°C. Only buildings that have undergone UK NZCBS Verification can refer to themselves as Net Zero Carbon Aligned, and such claims can be checked on the UK NZCBS Buildings Register.
Offsets can not be used to meet the requirements of the Standard, but once the requirements have been met, approved types of offsets, including renewable procurement, can be used to gain the optional "plus offsets" recognition as part of a Net Zero Carbon Aligned claim.
2
What do you mean when you say that the Standard is "science-based"?
The Standard sets science-based limits and targets. According to the Science Based Targets Initiative, these are considered ‘science-based’ if they are in line with what the latest climate science deems necessary to meet the goals of the Paris Agreement. We have apportioned the UK’s remaining carbon budget to determine a budget for the built environment, and this has been used to set limits and targets.
3
Can the Standard ever be 1.5°C-aligned if the world is set to pass that point?
Even if other sectors exceed their 1.5°C carbon budget, it is important for the built environment to aim to stay within its own. The 1.5°C pathway sets the budget - the Standard sets out what individual buildings must achieve to stay within it. This will need to be continually reviewed based on discussion and agreement between ours and other sectors.
4
Is this a certification scheme / assessment scheme / tool?
The UK Net Zero Carbon Buildings Standard itself is a standard, and not a scheme or tool. It defines a consistent set of requirements for a building to be defined as ‘Net Zero Carbon Aligned’.
To provide verification against this definition, the UK NZCBS Verification scheme has been developed in partnership with Bureau Veritas, which must then be used to verify that the requirements of the Standard have been met.
Technical
5
What does the Standard set limits and targets for?
The Standard sets limits and targets for a range of requirements, including embodied carbon, operational energy, fossil fuel free, and on-site renewables. It also defines mandatory reporting requirements for certain metrics in which there re no limits or targets, such as operational water use. Refer to the UK Net Zero Carbon Buildings Standard for a full list of requirements.
6
What do you mean by "limits and targets"?
"Limit" is used to describe maximum requirements that must not be exceeded, such as an embodied carbon limit. "Target" is used where describing a minimum requirement, such as an on-site renewable power generation target.
7
Why is Whole Life Carbon not used as a single metric?
We need to stay within a renewable energy budget for the UK, if the country is to reach Net Zero Carbon. This means that energy use is as important as carbon use, and so limits for embodied carbon and operational energy are set based on their allocated share of the whole-life carbon budget, and the renewable energy budget, for the built environment.
8
Does the Standard advocate specific design solutions or accreditations, such as Passivhaus?
No. The Standard is solutions agnostic. The Standard sets out out the performance requirements, but how the requirements are met is not mandated. However, certain industry schemes and standards have been Deemed to Satisfy certain aspects of the Standard, which means achieving certification to such schemes can be used as evidence for having met some of the Standard's requirements. Refer to Annex C of the Standard for details.
Application
9
What types of buildings does the Standard apply to?
The Standard applies to new buildings, existing buildings and retrofits. The initial focus is on the most common building typologies, especially those for which industry stakeholders already have robust performance data available to develop the targets and limits.
10
Who is the Standard written for?
It is for anyone who wants to either fund, procure, design, or specify a Net Zero Carbon building, and anyone wanting to demonstrate that their building is Net Zero Carbon in accordance with an industry-agreed Standard. As a robust industry-backed initiative, the Standard may also be useful to policymakers looking to create policy to support a Net Zero Carbon transition.
11
Are there different limits and targets for heritage buildings?
During the Standard's development, we had assembled a working group looking specifically at the challenge of applying a Net Zero Carbon Standard to historic buildings or those with heritage aspects. After extensive consultation and analysis, heritage buildings do not have a specialised approach in the Standard, but its methodology can be applied to them as with any other existing buildings. We continue to engage with sector representatives and collect data to support the application of the Standard to heritage buildings.
Creation
12
How have you decided how much carbon budget the buildings sector gets?
An extensive literature review has shown that there is no agreed method for how to define a sectoral carbon or energy budget for the built environment, either in the UK or elsewhere. Analytical work was done to derive robust carbon and energy budgets from the Climate Change Committee’s Sixth Carbon Budget, and the National Grid ESO. The carbon budget was ‘upscaled’ to reflect consumption-based emissions, rather than territorial (i.e., including embodied emissions that originate outside of the UK).
13
Who is making the decisions behind the Standard?
The Standard development has been led collaboratively by eight of the leading built environment organisations (referred to as the Founding Member Organisations), who each have representation on the Standard's Technical Steering Group and Governance Board. The technical development has been supported by over 350 expert volunteers working in a series of Task Groups and Sector Groups, in addition to representatives for over 200 Pilot Projects that underwent testing in 2025.
During the development of Version 1, Net Zero Carbon Buildings Standard Limited was established as a company to lead the development and implementation of the Standard, under the leadership of the Founding Member Organisations.
14
When was the Standard introduced?
Version 1 of the Standard was published in March 2026, following a year of Pilot Testing. We intend to produce subsequent versions of the Standard periodically, to address future changes in Carbon and Energy budgets, materials decarbonisation, and continuing industry feedback.
15
Why did it take so long to write?
The Standard is the industry's first unified definition for Net Zero Carbon Aligned Buildings in the UK. It is the first initiative globally to set balanced, science-based limits that balance "bottom-up" measured performance data with "top-down" national carbon and energy budgets that have been downscaled for the industry. Its limits and sectors cover a broader scope than any guidance or standards that previously existed in the UK built environment.
It had to be sufficiently robust to ensure that it would continue to be useful throughout the country's transition to Net Zero. Achieving this robustness required; consensus to be developed and achieved from the full range of built environment stakeholders (each with different priorities and perspectives); management of the delivery of work by hundreds of volunteers working around other pressing commitments; and striving to back up all decisions with data as far as possible.
16
What would happen if the "bottom up performance levels" and "top down pathways" didn't meet?
The top-down budgets have been balanced with the bottom-up performance levels through appropriate redistribution of carbon and energy budgets. Refer to the technical explanatory resources to learn more about our work on the balancing model.
Interaction & Impact
17
How does the Standard interface with existing Net Zero Carbon Standards for the UK Built Environment, such as the NHS NZ Standard, and the Scottish Net Zero Public Sector Buildings Standard?
The Standard is a voluntary document that can be used across the UK on many different building types.
Requirements for healthcare buildings in the Standard have been aligned with the NHS NZ Standard as far as possible, and the NHS standard's operational energy targets are those referred to in the Standard.
Now that the Standard has been published, its predecessors (other voluntary schemes, such as the RIBA 2030 Climate Challenge) are intended to be updated to align with the Standard's requirements.
18
How does the Standard interface with the Science-Based Targets Initiative (SBTi) buildings target-setting tool?
The Standard is an asset-level set of performance requirements covering embodied carbon, operational energy, and several other Net Zero Carbon related metrics, for UK buildings. The SBTi buildings guidance provides a target setting approach at the corporate level for companies in the building sector, designed to be applicable globally.
We continue to engage with other schemes such as SBTi to further detail the alignment between initiatives.
19
How does the Standard interface with other existing voluntary targets such as LETI/RIBA 2030 Climate Challenge targets etc?
The Standard is the industry's first unified definition for Net Zero Carbon Aligned buildings. The limits and targets defined within the Standard reflect the most up-to-date knowledge and expertise on what's needed to remain within a 1.5°C warming scenario.
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Now that the Standard has been published, its predecessors (other voluntary schemes, such as the RIBA 2030 Climate Challenge) are intended to be updated to align with the Standard's requirements.
20
How does the standard interact with PAS 2080?
PAS2080 is a carbon management standard, whilst the UK Net Zero Carbon Buildings Standard sets the requirements for individual projects within the wider system of the UK built environment. The aim is for the Standard to be fully compatible with PAS2080 processes.
21
Does the Standard inform regulation?
This is a voluntary Standard for use by those wishing to describe a building as Net Zero Carbon Aligned. It could, however, be used to support policymakers in setting robust requirements that deliver buildings aligned with a 1.5°C decarbonisation pathway for the UK.
The Governance Board and Technical Steering Group are open to engagement with local and national planning authorities to enable this.
22
How does the Standard influence specification criteria?
The Standard can influence specification criteria for buildings through mandating certain performance limits, targets and requirements to allow buildings to be classified as Net Zero Carbon Aligned. These limits, targets and requirements can influence system and material choices and specifications.