Create a high-performance building at little or no extra cost

The AECB Building Standard is aimed at those wishing to create high-performance buildings using widely available technology at little or no extra cost. We estimate that this low-risk option will reduce overall CO2 emissions by 70% compared to the UK average for buildings of each type – a highly significant result given the relative ease and low cost with which this standard can be met. Individual self-builders and large-scale residential and non-residential developers could make a valuable contribution to low-carbon building by meeting the AECB Building Standard.

Where to start?


Your existing project manager may have the experience necessary to create an AECB Building Standard project or you can employ a certified Passivhaus designer/consultant within your design team. Not only have they got the skills, they also have the practical knowledge about what works and what doesn’t.

Architects and Engineers

If you are about to embark upon an AECB Building Standard project and you’re already a certified Passivhaus designer/consultant then you pretty much know all you need to know. Now all you need to do is execute what you already know to the best of your ability.
If you’re not a certified Passivhaus designer/consultant and do not have the necessary experience then you may wish to become trained. You will not only learn how to use the Passivhaus Planning Package (the fundamental design tool used in AECB Building Standard projects), you will also discover how to mitigate thermal bridging and minimise air leakage.


AECB Building Standard is not without its challenges. Providing your design team has experience and a good track record then you are in a good position. If not you may consider employing an appropriately experienced person or a certified Passivhaus designer/consultant to review the design, construction details and PHPP calculations.
One of the biggest risks on large projects is the loss of knowledge and skills while you’re on site. If not managed properly this can set you back. One of the best things you can do is ensure quality, consistency and continuity of onsite labour. After a series of trade specific tool box talks it’s simply a case of being careful and diligent.


One of the primary benefits of AECB Building Standard is choice. Working with your design team you will be able to determine the fabric standards and ventilation systems that suit your needs. This gives you the opportunity to consider how ventilation systems will be used and maintained throughout the project lifecycle without being bound to mechanical ventilation heat recovery.
At the same time, by focusing upon a fabric first methodology, you can make the most of passive and low energy design and technology. This serves to reduce energy demand and minimise lifecycle cost.

Architects and Engineers

AECB Building Standard is an ideal vehicle for conscientious professionals committed to creating sustainable low energy, low carbon buildings. If you lack the knowledge and experience you can employ a certified Passivhaus designer/consultant although this is not mandatory.


If you want to demonstrate your prowess at construction and the quality of craftsmanship of your trades, AECB Building Standard will suit you down to the ground. If you have not built a Passivhaus then AECB Building Standard provides an opportunity to stretch yourself without such an onerous airtightness target. Once you have the experience you will be able to progress on to Passivhaus with much greater confidence.

No, however the design & detailing advice to support building to the AECB and Passivhaus Standard can only be downloaded free of charge by an AECB member, so one of the design team should be a member.

If you are applying the building standard to a retrofit project you may need training in delivering moisture-robust energy efficiency measures. Read about our advanced retrofit training course which is studied online at your own convenience here.

Many individual AECB members have undertaken the CarbonLite Retrofit training and are now graduates. Those who are integrating this training into their professional work are listed here

Independent certification was considered as it could, in principal, be provided by Passivhaus certifiers. However, the AECB opted to provide a less formal option for its members and therefore a self certification route has been developed.  This means the self certifier (typically the building’s energy consultant) takes responsibility for certification and for underwriting the standard claim. The AECB has provided a form of declaration for completion by the certifying consultant but will deliberately not audit or take responsibility for the certification.

The AECB self certification process is designed to make explicit the project’s claim to be a low energy design and to provide the consumer with a degree of protection under trading standards – without the AECB having to get involved in quality control and legal matters.

This approach puts the responsibility for performance claims clearly with the person signing the certificate and a duty of care on the client to ensure that the consultant is competent and suitably insured.

During 2020 the AECB is assessing a move to allow only CEPH certified trades/designers/consultants and other suitably qualified individuals to certify to the standard. Any change to current arrangements will be communicated in good time to accomodate projects that have, or will have engaged certifiers.

Guide prices for domestic buildings (per unit or block)
Floor Area m2 AECB members Non members
up to 250m2 £100 £250
251 – 1500m2 £150 £750
1501m2 and < 3000m2 £180 £900
3001m2 and above £250 £1250

All prices are plus VAT. 

Charges for non-domestic buildings will be based on the above prices, based on floor area with an additional cost of up to 50%, the final cost to be advised on application to cover the relevant complexity of the project.


There are three alternative options open to certifiers. They are:
1) Dwelling by Dwelling
2) Dwelling Type and Energy Sub-type
3) Building-By-Building

Dwelling by Dwelling
Some clients want each dwelling-type to be certified. This approach closely reflects the methodology used for EPCs. This approach is most labour intensive and results in a certain amount of duplication. As processing takes longer for the certifier and the AECB this certification approach incurs a higher certification fee.

Dwelling Type and Energy Sub-type
On the basis that all dwellings have the same orientation and that there are terraces or flats (rather than detached homes), energy sub-types often occur. This happens when you have mid-terrace and end terrace units. From the perspective of energy performance and certification each dwelling-type could have two (or more) energy sub-types due to the exposure/sheltering of mid-terrace and end terrace units. Energy sub-types also occur where changes to orientation or shading. Whilst the certification fee can be a little lower than other options, because this approach is labour intensive the total cost of certification (which includes the certifiers’ time) is higher.
It may depend on what the end user would like to see: for example in a project where the future owner of a mid-terrace unit wanted to see their exact energy performance a separate calculation (with additional fees) was required.

Where a number of different self-contained units are contained within one continuous thermal envelope it is possible to certify a complete building rather than each unit or energy type. Compared to the ‘Dwelling by Dwelling’ and ‘Dwelling Type and Energy Sub-type’ models there are advantages to adopting a ‘Building-by-Building’ strategy, these include: reduced modelling (saved time) and; reduced evidence collation management (saved time). The house numbers for all the units in each building must be included in the project name which is included on the AECB certificate for that building.

Whilst the certification fee can be a little higher the total cost of certification (which includes the certifiers’ time) is significantly reduced. This strategy typically tends to be used by designers and certifiers certifying to the Passivhaus Standard.

Note: the AECB Standard generally aligns to the Passivhaus methodology: this does not currently align with the EPC methodology and traditional expectations for resale.


Working out the certification fee Illustrated by a worked example for each:

1) Dwelling by Dwelling

Number: 34
Assumed area: up to 250m2
Fee: @ £100 / certificate
Total Fee: £3,400 plus VAT

2) Dwelling Type and Energy Sub-type

- Semi-detached: 1 unit
- Apartments: 2 units
Block A1: 6 units (End-terrace: 2, Mid-terrace: 1, Apartments: End-terrace: 2, Apartments: Mid-terrace: 1)
- Block A2: 5 units (GF Apartments: 2, FF Apartments: 3)

Total: 14 Dwelling Energy types
Assumed area: up to 250m2
Fee: @ £100 / certificate
Total Fee: £1400 plus VAT


3) Building-By-Building

Number: 6
Assumed area: 251 – 1500m2
Fee: @ £150 / certificate
Total Fee: £900 plus VAT

Many members of the AECB are experienced in low energy building.  You can search our members in our Members Directory or find a certified Passivhaus designer/consultant database of certified Passive House designers/consultants. Please note that when searching our Members Directory, we are not an accrediting body and so membership does not guarantee competence.

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