Our Offices: Net Zero Carbon 2020-21

Our Offices: Net Zero Carbon 2020-21

June 2022

We’re proud to report that the five office buildings we occupy have achieved net zero operational carbon verification for the period January 2020 to January 2021. The work was carried out to the latest requirements of the UKGBC Net Zero Carbon Building Framework, updated in March 2021. The work goes beyond the requirements for just the current period and also considers needs and proposals for deep decarbonisation between now and 2035.

The full report describing the work carried out to achieve net zero for our offices can be downloaded here.

The third party audit and verification of the work was carried out by Hoare Lea; their statement can be downloaded here.


The previous net zero assessment and verification we achieved for our five offices was carried out in 2019. Since then, the UKGBC requirements have undergone substantial development; the new requirements being significantly more onerous. The current set of UKGBC net zero framework documents (for offices) are the following:

 The main developments / new requirements that define the higher standard of net zero carbon that our offices now meet are the following:

  • There are now energy use targets specified for offices that mustn’t be exceeded for office buildings to be considered net zero carbon compatible. The targets get progressively lower (more onerous) over the coming decade.
  • For buildings that don’t meet the energy use targets, it is required to publish an action plan for reducing energy consumption in forthcoming years.
  • For buildings that use fossil fuels on site (e.g. gas boilers), it is required to publish trajectory plans to phase out their use by the next replacement cycle.
  • There are now requirements that grid imported electricity should be from renewable tariffs and/or use methods that promote the national development of additional renewable generation capacity.
  • There are new quality requirements on the types of carbon offsetting permitted to be used to achieve net zero emissions.


Targets for net zero carbon offices

The following diagram is adapted from the UKGBC Energy Performance Targets For Offices document and provides energy uses targets for net zero carbon-compatible offices buildings. The diagram also shows which target type we used for each of our offices.

Energy use targets for net zero carbon-compatible office buildings. The upper set are published by the UKGBC. The lower set we developed in conjunction with the UKGBC to address a building design scenario not covered by the UKGBC publication.

The UKGBC published energy targets are based on the assumption that tenant areas in office buildings are served by certain Landlord owned and operated energy systems (such has heating and mechanical ventilation). Our London and Cambridge office designs don’t fit this assumption, in both cases we are tenants, but we own and operate our own heating and ventilation plant. In the case of our Cambridge office, this issue was addressed by us working in conjunction with the UKGBC to develop a custom set of energy targets (illustrated above).

Current energy performance of our offices

The charts below show the as-measured (or, for Bristol, estimated) energy consumption data of our five offices for the period January 2020 to January 2021. The data shows that all our offices, except Bristol, meet their corresponding UKGBC 2020-2025 interim energy target. Our Bristol office doesn’t have metering and so a (pessimistic) estimate was used. Overall, the energy consumption of our five-office portfolio (including the estimate for Bristol) is about 5% less than the (area weighted) corresponding UKGBC 2020-2025 interim target for net zero carbon office buildings.

The majority of our energy consumption occurs in our largest office, London. The energy use in Manchester, Edinburgh and Cambridge was significantly reduced due to the effect of the coronavirus pandemic (offices closed, people working from home). The same isn’t true for London as this building was still being used fairly intensively (to facilitate home working) during the same period.

Max Fordham offices’ annual energy consumption 2020-2021


The energy use estimate for our Bristol office didn’t meet the UKGBC interim energy use target, so, to achieve verified net zero status, it was required to provide an energy use reduction action plan for this building. This is somewhat misleading, as, in fact we don’t know the actual energy use because the Bristol office has no metering to our tenancy. The action plan provided was to install metering so that the true picture would be available at the next assessment date. However, since then we’ve actually decided to move office, meaning that our next energy assessment will be for a different building.

The work we carried out went beyond the minimum needed to achieve net zero status for the period being assessed (2020-2021) and looked at what would need to be done for each office between now and 2035 to meet the future UKGBC energy targets. The chart below illustrates some of the findings, using 2019 pre-pandemic data as the baseline.

Max Fordham offices’ baseline energy consumption (2019) compared to UKGBC future targets for net zero carbon office buildings

The work has shown that in order to meet the UKGBC 2025 target, around a 30% energy use reduction is required (or recommended, depending on one’s interpretation) at our London office. We’re currently undertaking feasibility studies on how this might be achieved. Likely candidates include measures such as replacing gas boilers with heat pumps, improving the efficiency of IT systems, and simple building fabric improvements. More complex interventions such as insulating the external walls and adding MVHR are also being considered.

Our London and Manchester offices are both within Grade II listed historic buildings. The UKGBC net zero framework recognises that these types of buildings may require different energy targets, stating “the upgrading of existing offices should consider concessions for heritage buildings”. This is something we are considering.


The Rotunda – our London Office. A feasibility study is underway looking at how the building’s gas boilers can be replaced with air source heat pumps.

To achieve verified net zero status, one must provide transition plans for the phasing out of the use of fossil fuels at the next replacement cycle. Our Cambridge office already uses electricity only, so no plan is required for this building. The only other office where we own and operate the heating system is London, where the gas boilers will be due for replacement around 2025. We’re in the process of a feasibility study looking at how the boilers could be replaced with electric heat pumps. Air source currently looks like the most likely solution, but ground/water source is also being considered. As with most gas boiler to heat pump conversion projects on existing buildings, there are a range of challenges including: assessment of the building electric supply, how to work with lower water temperatures provided by heat pumps, and where to site the units. Air source heat pumps are physically much bigger and noisier than gas boilers; finding a place to site them is not trivial.

For our Edinburgh and Manchester offices we don’t own or operate the heating systems, our landlords do. In these cases we’re going to try to persuade our landlords to make the switch from gas boilers to heat pumps in the near future.


Our Edinburgh office. A study is underway examining the feasibility of adding PV (solar power) panels to all of our offices’ buildings.

Our London office has an on-site renewable electricity source, 20m² PV array (a size equivalent to about 1% of the floor area) which supplies about 1% of the annual office energy demand. The remaining electricity use in London is grid imported using a tariff from Green Energy UK, one of the few “High Quality Green Tariffs” recognised by the UKGBC as being genuinely 100% renewable and adequately invests in additional renewable capacity. (The other recognised high quality green tariffs are ones from Ecotricty and Good Energy). This combination of on-site renewable generation and High Quality Green Tariffs means that the London electricity supply is 100% renewable and no offsetting is required for this aspect of our energy use.

Our other offices have electricity tariffs organised by our Landlord that we are not in control of. In this scenario, the UKGBC net zero framework required us to purchase and retire Renewable Energy Guarantees of Origin (REGO) certificates, which we did. This means that some renewable energy generation certificates were removed from the national pool, which, assuming there is a demand for them, indirectly stimulates the market to build more renewable energy power stations.   

Our non-London offices don’t yet have on-site renewable generation. Part of our future decarbonisation plans is to undertake feasibility studies to establish if and how it might be possible to incorporate (or, in the case of London, increase the extent of) on-site PV panels on to the buildings.


The total operational emissions for our five-office portfolio for the period being assessed that required offsetting was 38 tCO2e. We used the UKGBC Transition Fund approach, voluntarily paying £85/tCO2e, which exceed the UKGBC recommend carbon price of £70/tCO2e.

As per the requirements of the UKGBC Net Zero Carbon Framework, the Residual Carbon Balance (38 tCO2e) was required to be offset (to achieve net zero) using verified offset types. There are only two available types that qualify: Gold Standard or VCS type offsets and none of these are UK based. We purchased VCS type offsetting credits (at 15 £/tCO2e) from the The Katingan Project, which is a peatland and forest ecosystem restoration project in Kalimantan, Indonesia (Borneo). 

The Remainder of the Transition Fund  (70 £/tCO2e x 38 tCO2e) doesn’t need to meet as stringent quality standards and was used to fund UK based woodland creation and peatland restoration projects. These projects are not yet verified (haven’t reached maturity) but are underway and planned to do so in the future.


Our net zero carbon buildings report and associated documents were audited by net zero carbon specialists Hoare Lea, who have confirmed that our 5-office portfolio achieves net zero carbon (for operational emissions) in accordance with the UKGBC Net Zero Carbon Building Framework for the period 2020 to 2021. Thank you to Hoare Lea for the diligent audit and constructive criticism of the work, which helped us to achieve net zero. Their report can be seen here.


In common with many other businesses, we don’t own any of the buildings we occupy. In all cases, we are tenants in multi-tenanted buildings. This arrangement presents a challenge to decarbonising our offices and any other tenanted building, as many of the types of required works (such as improving building fabric, changing the heating systems and/or installing PV) require landlords to carry them out and/or provide permission for tenants to do the work themselves. Landlords may not want to do the work or have others carry it out.  Even if they do, they might offer little or no financial contribution. In these types of cases, tenants such as ourselves, who want to decarbonise as quickly as possible, then need to consider how much they want to invest in someone else’s property and/or potentially moving building if their landlord’s decarbonisation plans are not aligned with their own.

On the other hand, decarbonisation presents an opportunity for landlords. Net zero carbon compatible buildings (that is, ones with very low energy demands and that don’t use fossil fuels) are in demand, and the demand is likely to increase over the next few years. It is likely that capital and rental values will be higher for net zero carbon compatible buildings. Engaging with the process now is likely to be easier and potentially cheaper than leaving it till the last minute.


Start your decarbonisation journey now

We encourage all building owners and tenants to take action to address the climate emergency and begin their decarbonisation journey now. An excellent way to do this is to undertake the process of achieving UKGBC verified net zero carbon status (for operational energy related emissions) for the current year. We encourage all businesses (above a certain size) to do so, in particular those involved in the construction sector such as architects, engineers, project managers, contractors, etc. In principle, any building can be assessed and achieve net zero for the current period, even if the building doesn’t yet meet the recommended standards of energy efficiency or if it uses fossil fuels, such as gas. As explained in this article, part of achieving verified net zero status for the current period involves setting out decarbonisation plans for the future.

In general, we encourage all building owners and tenants to achieve UKGBC net zero carbon staus, however, the UKGBC process does have some complexities and costs, and may be out of reach for very small buildings and businesses such as individual homes. To address this challenge we encourage the UKGBC to develop a simplified version targeted at these types of buildings/owners. That said, Feilden Fowles Architects have done it (with some light touch help from ourselves), they are a business with approximately 20 staff occupying a building of 160m2 floor area. You can read their report here.

How we can help

We can help you to achieve verified UKGBC net zero carbon status for the building you own or lease. We can also help you to develop future decarbonisation plans so that your buildings and businesses are compatible with the needs of a net zero carbon future. The services we provide can help you with identifying needs, developing design solutions, undertaking energy and carbon analyses, renewable energy procurement, carbon offsetting, reporting, auditing and, in some cases securing funding. Some example projects we have undertaken or are undertaking are the following:

To discuss your project’s decarbonisation needs and how we could help you, please feel free to get in touch with us by phone or email.