Ben shares the journey towards 150 Holborn’s BREEAM Outstanding and LEED Platinum certifications, and discusses the ongoing work required in maintaining these standards.
I’ve been with Dar for just over 10 years now. I’m in the sustainability team in London and my primary focus is developing sustainable strategies for Dar masterplan projects and also overseeing sustainable certifications for projects within the UK, Europe, and in the MENA region. I’m also the HSE Manager for Dar UK (London office), the Compliance Officer, and the Chair of the Corporate Risk Committee.
Prior to joining Dar, I was based in the Middle East for eight years in Dubai and Qatar, and that experience has been very useful, given we have so many Middle Eastern projects.
Buildings and construction activities contribute to 36% of the global energy use and 39% of carbon emissions, and it’s vital we find a way to reduce these figures.
By following a defined sustainable strategy, we can better understand the associated environmental impacts during the lifecycle of building, and then mitigate them.
As part of this, we use sustainable certification systems (such as BREEAM or LEED) to assess a building or a construction project’s performance from a sustainability and environmental perspective, and because they allow comparison across the industry.
For example, they allow you to show (with robust evidence) how much more energy efficient this building is compared to another typical building. We can demonstrate the U-Value of the facade (how well a material or construction resists heat loss), show the capabilities of the smart meters within the building, and confirm how much renewable energy is generated by the building.
All of these design features earn the project points, and then you can get additional points for, say, how much renewable energy you generate – is it 1%? 3%? 5%? 10%? Once you add up all those points, it gets you to a certain certification level.
For BREEAM, which is the UK sustainable certification standard, you have levels including Very Good (55%), Excellent (70%), and Outstanding (85%). Therefore, if you want to go for the higher certification levels, you need to get more points. And some of the points involve you having to do additional work, often in the early stages of projects, so you really need to be engaged at the actual concept design stage, as I was with 150 Holborn.
The project started in early 2015, and I was there at the project kick-off meeting back in June 2015 along with Scott Smith. As with all projects over a long period of time, team members change so I’ve been fortunate to have seen this project through from its inception to today, post-occupancy, and lived that full project journey, which is rare.
Having that continual presence has been very useful as it means we have knowledge of the design path followed and the reasons behind any deviations from the original vision – both positive and negative changes..
Yes, particularly because my role was to run the BREEAM and LEED certifications from the very beginning. When we spoke with the local authority (London Borough of Camden), they gave us 44 planning conditions that the building needed to achieve, and one of those was that 150 Holborn needed to achieve BREEAM Excellent. That was set in stone – Camden wouldn’t sign off the building unless we hit that.
The client (Dar) wanted the building to achieve global certification through LEED, aiming for a Platinum rating. When we looked at the types of credits we’d need to target for LEED Platinum, we realised they were very similar for BREEAM Outstanding, so we thought, why don’t we push for the higher level of certification here too? And that’s what we had in the back of our heads from the outset.
However, when you’re looking at the design of a project, factoring in the sustainability conditions set by the planning authority and third parties, environmental certification is important but shouldn’t be a driving factor in the design visioning as this can cloud decision making.
For instance, Thames Water said we needed to reduce the amount of runoff water coming from our site by 50%, to prevent excess storm rainwater adding to the overflows of sewage into the Thames. So, we had to put in an attenuation tank beneath the loading bay to capture and hold onto any rainfall until the storm passes and there’s less water in the pipes, and then we can release that excess water so it doesn’t overload the system.
So, we have planning and third party conditions that are set in stone and then we have what the client wanted to achieve as well, the actual vision for the project.
At the very beginning we had a blue sky workshop with sustainability representatives from all collaborative brands (Architect, PM, QS, Engineer) collectively visioning what we wanted the building to look like. And we had a few off the wall ideas – someone wanted to have a meadow on the roof with a goat to keep it under control. And there was a desire to have beehives up there – something we’re still planning to have in the near future, so I need to check people aren’t allergic to bees, for example.
Exactly. So, we had all these ideas up on a wall and we had to decide which ones were actually feasible, practical, and whether the technology was in place.
For example, 150 Holborn has a brand new gas boiler, which is a very old-fashioned thing to have these days, when climate change is at the top of the agenda. However, that wasn’t our original plan – Introba originally suggested either a ground-source heat-pump (though studies showed there was not enough building footprint or external area for them to be effective) or air-source heat-pumps (ASHP) – but it was felt the ASHP units would take up too much roof space.
In addition, the local authorities at the time did not view heat pumps as the low-carbon option that they do now, so even though we really pushed for heat pumps as part of a net zero carbon approach, we had to put in an old fashioned gas boiler. This odd stance of the local authority towards heat pump technology was an impetus behind Introba establishing the Low Energy Transformation Initiative (LETI) in 2017 to support the transition of London’s built environment to a zero carbon future.
Now we’re going to have to think further down the decarbonisation pathway, do we want to rip out this perfectly good gas boiler out of the building in order to meet Sidara‘s targets for net zero carbon for operational buildings? It’s a big quandary.
And then we had other ideas, like water suppression in case of fire. Having a sprinkler system in place, we suggested a mist suppression system rather than using rainfall. That sort of sprinkler would involve a water tank about ¼ of the size of the one that’s down the basement now, which would give us more room for other things. But because at the time there was no ISO standard in place, our insurance companies wouldn’t allow us to put one in. So, yet again, we had to go with what’s now an old-fashioned sprinkler system.
It’s very frustrating. We came up with all these great ideas. We wanted to put them in. But we were hampered by either insurance companies or local authorities being nervous of new technology.
Yes, exactly. And of course we were a little constrained by budget sometimes as to what we could achieve. So the fact that we’re now in a situation where the building is on track for getting LEED Platinum and BREEAM Outstanding is quite amazing. We’ve just got the Outstanding certification for the Retail Units (86.7%), and then for the rest of the building we’re on track for about 97.2%. Which will be the second highest office building rating in London, the only one above it is the Bloomberg building.
I think we can be very proud that we’ve achieved the highest certification levels, and one of the reasons is because we’ve been in charge of the direction of the sustainability journey from the very beginning.
We identified the credits that a lot of projects don’t target, either because they’ll take a lot of effort, or because it’s difficult to understand what’s actually needed. And we decided to target them, firstly because we had the time and energy to go for it and secondly, because 150 Holborn would be a good case study for us to demonstrate how we can achieve some of the “more difficult” credits. So, we basically targeted every single credit that’s possible in the BREEAM manual.
There is that as well. When I meet other clients I’m doing BREEAM certifications for, I’ll ask if they want to go for certain credits, which will take extra time and cost more. And sometimes their response is, we’re already over the threshold for Excellent (70%), why do we need to push any further?
And I’ll say that the extra credits are in line with your vision for the building, and you can do it. But they often come back and say no, we don’t want to spend any extra money, or have the architects bill us for extra time. Whereas at 150 Holborn, we can show that we analysed the feasibility of these credits and can show they actually require minimal additional input to achieve.
One of the the overriding considerations in the building design was the budget, and this informed some of the decisions made with regard to the types of materials chosen or systems installed. For instance, we installed double-glazed windows over triple-glazed options, and a 4 pipe fan coil unit (FCU) system with a gas boiler and chiller is a cheaper capital expenditure option than an air-source heat-pump system.
And, as I mentioned, some of the technology proposed was ahead of its time. We also wanted to look at having thinner columns in the building, but some of the structural engineers were a little bit cautious on how this was a non-traditional approach.
But the biggest challenges have been post-construction. Getting the certification evidence (such as design specifications, energy calculations and as-built drawings) from the design team has been perfectly fine, but getting it from the contractor can be a challenge, as a number of the people have moved on to other projects so it takes a while to find where it is!
I guess something else I’m proud of is that we were able to realise most of our sustainability vision. A lot of the things we pushed for from the very beginning we’ve actually managed to implement. A lot of that is because we’re building in Camden, which has some of the more stringent sustainability commitments of any London authority. They had a number of requirements we had to include in the design, and could not be value engineered out.
A good example of that is the greywater harvesting and rainwater harvesting. We’ve got a blue roof up on the roof terrace capturing the rainwater, transferring it down into a rainwater harvesting tank in the basement. The greywater harvesting collects the water from the showers and the wash hand basins, takes it down to the greywater harvesting tank, treats it, and then reuses it for flushing the toilets. We also move the rainwater into the greywater tank when there’s room to top it up and that is also treated for use.
I think it’s a really good narrative for the building to demonstrate how much we’re thinking about our use of water within here and reducing our demand on the system.
It’s important to be clear about what the client brief is from the beginning, and to make everyone aware of their commitments and responsibilities. You need people engaging from the very start of a project, not have some of them appointed at RIBA Stage 4. They need to understand what has to be in place from the beginning. So easy credits that require RIBA Stage 2 don’t get dropped because someone forgot to do it or wasn’t present at a meeting.
We identified all those things at the very beginning and communicated them clearly to everyone. These are the commitments we want from you and this is when we need this information through to us. So, that’s the most important thing, clear communication throughout the entire project.
The evidence that we’ve received for 150 Holborn has been top-notch, and I can now share that with other clients when they say, Ben, I don’t understand how to do this credit. I can say, here’s an example from another office building I’ve worked on and they can look and say, oh, I see, now I understand.
I’m still involved in the design evolution of 150 Holborn – both from a sustainability viewpoint, but also in a Principal Designer (health and safety) role to ensure that we are identifying and designing out any safety risks as soon as possible.
The next big thing we’re looking at is what does Day Two look like for 150 Holborn? We’ve got the BREEAM and LEED certifications in hand for the design and construction of the building, but there are other things we can do to improve the decarbonisation of our industry and ensure that we align with Sidara’s sustainability vision and commitments.
We have a cutting-edge smart building here, and the data it is providing allows us to analyse patterns (such as areas of the building with more foot traffic) and collect data on building performance (such as amount of energy generated by the solar panels) to demonstrate that not only have we designed the building, we’re continuing to look after it and improve it.
Often we work on projects in the Middle East where we build, for example, an absolutely brilliant sewage treatment plant. Five years later it’s broken down because no-one’s been maintaining it, no-one’s been trained to analyse the results.
But that’s what we’re doing here, we’re analysing results, picking things up, identifying if there are any sustainability improvements we can implement. And that’s one of the next challenges and narratives going forwards – is there a benefit in us targeting an additional sustainable certification related to the operation of an existing building to demonstrate this?