While early BIM slides had a digital thread looping operational data all the way around, in fact there are all sorts of breakpoints.

In order to substantially reduce operational carbon, our designs will adopt the following hierarchy:.Be Lean (passive): minimise the use of energy via passive design measures such as optimised form, orientation and window-to-wall ratio (WWR); design energy efficient facades that incorporate thermal insulation, high airtightness, external shading and solar control glazing; use of natural ventilation and thermal mass and design transitional spaces and low thermal expectation spaces.. Be Lean (active): minimise the use of energy via energy efficient lighting (LED, daylight and presence control sensors) and ventilation systems (demand control ventilation, low SFPs, heat recovery); use technologies such as waste-water heat recovery and specify energy efficient lifts and appliances/equipment.. Be Clean: connect to district heating networks that have plans for decarbonisation; explore plans and feasibility of local hydrogen district networks.. Be Green: use onsite low and zero carbon technologies such as air source heat pumps (ASHP), ground source heat pumps (GSHP), photovoltaic panels, solar collectors for domestic hot water and wind generation among others.. Be Smart: implement innovative technologies such as electric batteries, heat storage, post-occupancy evaluation and develop smart-metering systems..

Offset: any remaining carbon should be offset via Power Purchase Agreements (PPA) or recognised carbon offset schemes.Offsets used should be publicly disclosed.. An example of specific design strategies that Bryden Wood have adopted follow the proposed operational carbon hierarchy is shown in Figure 5 and is demonstrated with examples below..Step-by-step hierarchy for net zero operational carbon.

In order to substantially reduce embodied carbon, our designs will adopt the following hierarchy:.Build Nothing: identify opportunities to reuse existing structures, refurbish and reuse demolition materials onsite.

Build Less: optimise the building’s form, structure, structural grid, WWR and DfMA components; recommend the use of durable materials, design-out basements and false ceilings (exposed soffit); design spaces which are adaptable and can be easily deconstructed..

Build Clever: specify low carbon materials with a focus on the recycled content of steel and concrete and the use of timber; maximise the recycled content of finishes, use reclaimed floors and explore system’s rental; where possible use low GWP refrigerants and avoid VRF systems..Supplies Lead Wendy Bonard-Williams comments that her team are fortunate in this regard.

‘With the actual store rooms themselves,’ she says, ‘they’ve really thought about it.’.Raj Goel agrees when talking about the outpatient rooms.

‘There’s a clinic area next to each room,’ he says, ‘which is very good and that doesn’t always happen in other places.’.Maswiken comments upon the ample sizes of the recovery spaces.