Cora Kwiatkowski | Senior Associate | Stride Treglown
The reuse and refurbishment of existing buildings with their embodied carbon is intrinsically sustainable, provided that they can operate effectively and efficiently and that they are located in a sustainable location. But are all buildings really suitable for refurbishment and how can a balance between sustainability and return be struck?
Given that we are just climbing our way out of recession, investment still mainly concentrates on the refurbishment of our existing building stock. Whilst we can all get very excited about new technologies and renewables, we need to advance our thinking at the same time with regard to intelligent refurbishment options which include the potential for energy savings but are not only focused on these.
The European Union Energy Performance of Buildings Directive states that, alongside its target to construct zero-energy new buildings by 2020, renovation targets should aim to transform existing buildings into nearly zero-energy buildings, too. Quite often though, refurbishments lag behind and only the absolutely necessary works are carried out.
Existing buildings do pose significant challenges to the design of an accessible, flexible and sustainable environment fit for the next 25 years or longer. As most of the offices built in the 70s, 80s and 90s are now coming to the end of their useful life, we will often have to deal with low floor to floor heights, the absence of raised floors, asbestos, inefficient grids and unstable or insufficient structural elements such as low floor loadings.
Buildings constructed in the 1950s/ early 1960s will not have been designed with raised floors or suspended ceilings therefore requiring routing of the services around the perimeter. This increasing need for flexibility has led to many of these buildings already being demolished. It is important that clients are aware of the limitations of ‘their’ building early in the project and consider this in their viability studies.
Existing curtain walling, windows and external cladding are generally the elements most in need of replacement although repair can be considered in some cases. Curtain walls facades were introduced in the 1960s and have been the most typical façade since then. A replacement has not only the most potential to improve the performance of concrete-framed buildings, the most common construction method in the 1960s-1990s, but is also an opportunity to give buildings a facelift and a new appearance.
Generally, pre-1980s buildings would benefit the most from energy efficiency upgrades as the legal requirements for energy efficiency were very low. We should therefore look at ‘Fabric First’ and an improved air tightness before we consider renewables.
U-values for external walls were first introduced in England in 1965 as part of the Building Regulations and required 1.7 W/m2K. 1985 saw a second tightening to 0.60W/m2K for exposed walls, floor and ground floor. Now we are up to 0.28W/m2K for walls as new thermal elements for refurbished non-domestic buildings although many projects go beyond that.
Refurbished office buildings in sought-after locations can be competitive in a still quite tough commercial market place. A new BREEAM scheme has been launched in October 2014 to assess and improve the sustainability of UK building refurbishment and fit-out projects. It has been tailored to take account of the challenges of improving existing buildings, ensuring projects are assessed against the issues that each project can reasonably be expected to influence and is not judged on factors outside of their control. As this is quite a new initiative, it will be interesting to see how well it will be used by clients and developers. For new build projects, we already see less interest in BREEAM and more focus on EPC and DEC ratings by tenants.
Refurbishment gives not only an opportunity to increase energy efficiency and air tightness though but to remodel the whole building to improve the overall quality of the workplace which should be kept in mind. Increased use of daylight, active design, views out, user controls and better air ventilation in connection with potentially much needed noise reduction will increase productivity, health and well-being of the workforce and the satisfaction of the tenant. It is important that ‘soft’ factors are recognised more by clients, tenants and agents not just opportunities to increase floor area, reorganise circulation cores and improve the efficiency of the floor plate which is directly connected to an increase in the net lettable area and more profit. Although infilling light-wells might maximise development value, it needs to be weighed up against the quality of a deep plan working environment that will be created. Attractive Grade A office space that is light, airy and flexible will generate increased rental income and help to attract and retain staff.
Low flow water fittings with total washroom control, high efficiency light fittings with occupancy sensors and the potential provision of PVs on the roof are also easily added and should not be sacrificed even if the budget is tight.
A new, well designed façade will maximise useful daylight, give the building a modern appearance and can create a new landmark in the streetscape, advertising the building and the organisations occupying it.
Advantages for Owner- Occupiers
Whilst higher levels of insulation might slightly reduce the net internal floor area and increase the capital outlay, the tangible benefit of reducing carbon emissions and lower running costs should especially be favoured by future owners-occupiers.
Often, companies look at ‘flexible working’ options at the same time which might allow an overall reduction in size of the building by sharing workspace e.g. 10 people share 6-8 workstations. Public buildings will consequently generate savings for the local community and tax-payers as organisations suddenly need less space.
There is also an opportunity to improve business performance and productivity by tailoring internal modifications to changing workplace needs. New research about the ‘human office’ shows how to satisfy the demands of a more and more individual workforce. Special care should be taken not only by creating a variety of working environments but also when specifying materials; ‘healthy’ materials will have long term effects on absenteeism of staff. Wood, stone and live plants will bring ‘nature’ into our buildings; green settings and views out will lift the spirits and increase productivity.
We should explore all options for potential refurbishment before considering demolition and building new; should the building not be fit for its intended purpose anymore, there are always opportunities for conversions- it might not always be the best solution to impose a specific function to the building. We should be advising our clients on how to get the best out of their property, make sure it will be future-proof and not just refurbish for maximum value without creating inspiring working environments for happy users.