Greening Existing Buildings

Greening Existing Buildings

12.11.09

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The sustainable building movement is suffering a crisis of overhype and from focusing too often on new buildings.  We have seen a groundswell of ideas, legislation, measurements and examples of new green buildings in recent years, but very little to do with how we make existing buildings more sustainable. Considering that existing buildings make up 99% of our stock, it seems we have been spending most of our efforts solving 1% of the problem. Making existing buildings more sustainable will be the next big focus for the design industry, by default, as new build opportunities are limited by the recession and as landlords consider how best to market empty properties or as occupiers fit out or refurbish their offices to sweat their existing assets and simultaneously to respond to the wishes of staff, customers or shareholders to be green. 

Making our existing building stock more sustainable may also be the best way for the design industry to contribute to helping meet the aggressive government targets for 80% carbon reduction by 2050.

This article focuses on office buildings and the issues faced by either landlords or the occupiers when considering refurbishing and also the opportunities for designers to have an impact on the sustainability of existing offices.  The motivation to refurbish or not and the goals and challenges are different for the landlord as opposed to the occupier. I start from the landlord’s point of view.

The landlord’s motivation for refurbishment is geared around getting a return on their investment. Opportunities to refurbish come about due to lease breaks which mean fresh remarketing of buildings, EPC’s that have created a potential marketing advantage or problem for landlords, and the fact that the redevelopment option of many buildings may not be viable in the current recession. Also landlords cannot simply mothball empty buildings because of new vacant property taxes.

We are seeing greater interest from landlords to refurbish and for many landlords the interest to also create more sustainable buildings is there if it adds value. This is the holy grail…adding value. 

Value can mean different things including premium rents for green buildings. There is not enough clear evidence to say that green buildings demand higher rents, however a   recent Fuerst and McAllister research paper ‘New Evidence on the Green Building Rent and Price Premium’ measured LEED and Energy Star Rated buildings in the USA and concluded that green buildings demand on average 6% higher rents or sold for 35% premium to non LEED ones.  I am not sure any UK property developer could agree with those figures but there is a general concern among landlords that they might be true soon and no developer wants to be left behind.  A bigger fear is that EPC’s will create a them and us market for second hand space or that future legislation will make poor performing buildings subject to tax penalties born by the landlord. So sometimes reluctantly, most landlords are doing something toward greening their portfolios as part of their normal remarketing of empty buildings. More adventurous landlords are seeking other ways to add value in addition to creating a green building. Before they start getting green they have to often tackle an array of problems.

The major issues facing developer / landlords when considering refurbishment of older office buildings include:

Building Services that are past their life and no longer meet standards and regulations
DDA regulations for access
Part L regulations to provide adequate insulation when carrying out major refurbishment
Facades and windows that are single glazed or that are past their life
Common parts that are tired and run down and do not convey the right brand
Toilet provisions in cores that do not meet current regulations
Lack of raised floors
Low slab to slab height
Inadequate means of escape to suit high density occupation
Buildings which are occupied or partly occupied

The good news is that older buildings often have advantages over new including higher car parking ratio allowances, sometimes higher plot ratios, no risk of triggering section 106 agreements and can provide more character to the urban fabric or to the potential occupier.

 A new study and guide named Can Do which is about to be published by the BCO and carried out by Scott Brownrigg,  Hilson Moran and Gardiner & Theobold researched and reported on the viability of refurbishing existing buildings in a recession and the potential benefits and indicative costs. The study addressed a few myths regarding old buildings and their potential to refurbish.  

For example a few of the myths that the study tackled and provided evidence to dispel include:

It is more expensive to refurbish than build new.
There is less investment risk in new build.
Refurbishment of an occupied building is not an option
External fabric is not cost effective to replace.
A new building will be more sustainable.
Services replacement is not as effective as new build

The study dispelled all of the above and others and concluded that the key concerns include how far to take the refurbishment, and how to avoid spending more than necessary to maximise return on investment.. Four levels of intervention are discussed in the study, outlining the extent of the improvements to the building and relating them to an explicit £/m2 rate to demonstrate the level of risk versus reward. The Can Do guide identified Light Touch, Medium Intervention, Extensive Intervention and Comprehensive Intervention.

An ‘Extensive Refurbishment’ for example would include refreshing common parts, replacing ceilings and lighting,  floor coverings, plus a full replacement of building services, some building fabric changes, possible extensions to the floor plates and the remodelling of cores and communal areas.

 This level of refurbishment provides a typical 19% reduction in programme time to deliver vs a new building, can deliver a BREEAM Very Good rating and could cost on average about £140 / ft2 or 32% less than a new building. All compelling stuff.

 A good example of this is the Scott Brownrigg Interiors project for The Crown Estate in Guildford Business Park where the building was one of a group of four designed in the 1980’s and given a comprehensive makeover internally to the common parts and building services and extensive improvements to cladding and roofing and the introduction of a new roof light to transform the building.

 Motivation to refurbish for an occupier is often triggered by a lease break negotiation where the landlord contributes money to refurbish as part of the deal for a new lease. Or, it may be where an occupier has a medium or long term lease and the occupier would rather refurbish than consider relocating and trying to dispose of a lease in a flat market.  Or it can be a consolidation of staff from several buildings into one after downsizing. Whatever the motivator, the goal for most tenants is to create effective workspace that can support their business model and be inspirational to staff and visitors and have reasonable running costs for the term of the lease.   The green agenda is important to most organisations due to either grass roots interest from staff or a top level CSR policy that appeals to shareholders and staff alike.  I have not see any change in interest levels from corporate or public sector occupiers due to the recession. If anything the interest is greater from those occupiers that believe sustainable environments can deliver long term savings in running costs.

So what are the real challenges we face when refurbishing in a green way for an occupier?

 It is a common misconception that as architects or designers we have very little to contribute to a buildings sustainability when designing a fit out or refurbishment for the occupier. .  This is not true. There are several obvious areas of influence and a few not so obvious. The obvious ones are choice of materials and products, lighting (including natural light), building services and controls. The not so obvious ones are construction detailing, construction methods, and most importantly the influence designers have on the occupier’s behaviours and use of the building over time. The use of the building over its life impacts the carbon footprint/energy consumption/waste/environmental impact more than the initial construction.

I believe most designers specify products responsibly and consider for example: FSC timber, locally sourced products, products with recycled content, the ability to recycle materials after use, materials from renewable sources, materials that have low embedded energy, using alternatives to natural stone, using alternatives to vinyl and other petrochemical products if possible, and the list goes on. These are common sense choices and often have little cost implications.

We have to be reasonable in our specification of materials and realise that if we drill down into every product and interrogate every aspect of its sustainability credentials we probably will find something non sustainable. For example, the carpet tile industry is getting much better at using recycled products and the contents are often recyclable at least in part. However, at least one manufacturer does its recycling outside of the UK which may defeat the purpose but that should not preclude specifying that product.

Timber veneer is one of my pet peeves. The veneer process is very wasteful with about a 100% wastage factor for most species. Satin Walnut which seems to be everywhere these days is about 300% wastage because of the desire to book match the dark grain only and cut out the whitish sap inner part of the tree. Even when supplied from FSC sourced timber this seems a real shame. Fortunately some designers and clients are seeing the benefits in rethinking their aesthetics and excepting that walnut and other veneers can be very different and beautiful if we accept the inner sap part and the resultant change of colour and pattern through the grain. The recent fit out for law firm Norton Rose is a very good example of this aesthetic.

I mentioned the not so obvious areas of designers influence on a building’s sustainable credentials.  Construction detailing and construction methods are two of these. Designers and architects can sometimes over detail and over specify materials which results in unnecessary waste in manufacture or construction on site or the need for excessive energy consumption to fabricate. One obvious one is the way we detail and specify plasterboard partitions. Most standard partition details call for two skins of plasterboard either side of the studwork. This is good practice for rooms that require fire rating, good levels of acoustic separation or have a structural load applied such as heavy shelves. However is not necessary in may other applications where a singe skin can do.

My earlier point about the occupier’s use of buildings is where I believe there is even greater scope for designers to help our clients be green. Some of an occupier’s behaviour and operational protocols are developed in the briefing process and designers can flesh this out and then create the physical environment with new protocols in mind. The menu of these protocols can include:  Getting rid of rubbish bins, flexible working and desk sharing to increase density and uses less space per person, recycling, temperature set to 24 degrees in summer, lighting controls/ PIR’s, shutting down certain areas not in use, filtered water on tap not bottled water, providing cycle parking, showers, rainwater harvesting to flush toilets, blinds, exposed soffit/ chilled beam solutions and space planning the SW corners of buildings to respect the heat gain issues.

Realistically no project for an occupier can have all of these protocols, design solutions and products, but I advocate grasping a few green solutions and try to incorporate them into every project.

Scott Brownrigg Interiors project for a shipping company in Sea Containers House is an example of incorporating a few green solutions in the overall context of this major refurbishment such as filtered water, PIR lighting controls, centralised recycling points, and reusing some existing furniture. In addition extensive reconfiguration of cores and structure resulted in greater usable space and a complete revamp of M&E systems improved energy efficiencies. Steps like this will take us a long way to greening existing buildings.

An edited version of this article was published in the September 2009 issue of 'On Office' magazine

Ken Giannini is an Interior Design Director at Scott Brownrigg.