Posted: Monday, December 14, 2009 2:54 pm

Howard Evans, MD of SPV Special Projects examines the rationale regarding refurbishing commercial and public building envelopes, rather than redeveloping the entire property.

Recycling is not only one of the most cost effective ways to live a sustainable lifestyle, but it is also arguably the most well established. People in general and the construction industry in particular have been re-using materials since before records began. Indeed, many structures dating from the Roman occupation of Britain were plundered to build more humble abodes, and reclaimed bricks, slates, joinery and other materials continue to add visual appeal to contemporary developments today.

If we look further into this philosophy, however, it can be seen that refurbishing and thereby re-using entire buildings is an even more sustainable approach to property management or redevelopment. What is more, comparatively recent advancements in building technology are enabling specialist contractors and building consultants to not merely remodel existing structures, but also to dramatically improve their performance in terms of airtightness, thermal efficiency and acoustic insulations; making them far more attractive environments in which to work, shop or relax. The first requirement of any exterior refurbishment is of course access and careful consideration of the programme, together with the method statements for the various operations, will determine whether a structure needs to be fully scaffolded. Alternatively, cherry pickers, mast climbers, crane lifts or a combination of these different options may be utilised; with the consortia’s own consultants being able to take responsibility for health & safety as well as all CDM requirements.  And although all public accessible buildings are already required by legislation to have had risk assessments drawn up regarding the known or possible presence of any asbestos, initiating building work which might disturb the deadly fibres requires a complete new set of contingencies. In almost all cases the safe removal of the carcinogenic material – ubiquitously used in board and loose fill form up until the Seventies, will require the attention of a specialist contractor (part of the SPV Special Projects Consortium). Then by carefully planning and managing the ‘demolition’ phase of the project, where windows, original cladding systems and any other superseded aspects to the elevations are removed, both danger and disturbance to those living or working around the project can be reduced to an absolute minimum. Furthermore, disposal of waste off-site has risen dramatically in cost during recent times so segregation and even recycling can pay significant dividends. The over-cladding of existing buildings is a branch of construction technology which has burgeoned since the 1980s when Britain’s plethora of post-war high-rise buildings first began to require attention. Clients can choose between a vast array of treatments offering the opportunity to remodel facades at the same time as the physical performance is improved up to, or beyond the requirements of the current Building Regulations. In fact as long as the original structural floor-to-floor heights can accept all of the modern M&E installations, then there are few limitations on what can be achieved externally. Ventilated rainscreen systems are a popular choice for refurbishment applications as they permit the specifier to make the structure completely weather-tight, while various types or thicknesses of insulation can be utilised to reduce the U-value of the old wall construction. A grid of metal rails is normally employed to carry steel, aluminium or some other choice of cladding panel at a distance from the original building line. Exterior Wall Insulation or EWI is another alternative which also offers genuine scope for altering the appearance of a property, as well as improving its heat retention. In this instance, specialist contractors mechanically fix slabs of EPS, PU or other insulation to the substrate and then cover them with a proprietary render system that generally incorporates reinforcement mesh. Such is the flexibility of these treatments, however, that an otherwise drab, two-dimensional façade can be transformed into something radically different: perhaps with a neo-classical or ultra-modern architectural influence. As with overcladding systems, colour choice is virtually unlimited, while EWI can also be given the appearance of solid masonry by using brick slips or cutting joint lines into contrasting colours of render. It is almost certain the fenestration will require upgrading in tandem with the fabric of the structure, and here again the specifier is likely to find that budget is the only limitation on the improvements that can be achieved. Even if planning restrictions force the project team to replace old style steel windows “like for like”, the use of thicker IG units featuring gas filling and low-E coatings can still enable Part L to be complied with, while thermally broken frames and triple glazing can take U-values below 0.1 W/m 2 K. Furthermore, the use of high performance glass, decoupling gaskets and secondary glazing systems are all effective in reducing the transmission of traffic and other noise through to building interiors. Moving up to roof level, the traditional three-layer felt systems should be replaced with high performance elastomeric or single ply waterproofing systems over new additional insulation. And there are also technically advanced, lightweight steel framed systems that will facilitate flat-to-pitch conversions: changing the roofscape and greatly extending the service life of the covering. One of the accepted realities of a recession such as the UK is now experiencing is that the public becomes far more discerning about where and on what it spends its money.  In a strategic sense the same is true of businesses and any commercial landlord seeking to sell or rent property needs to consider the very positive advantages of carrying out a cost effective exterior refurbishment contract. The appearance of a building can be as big an influence as the location when it comes to the letting process; while the physical condition will be taken into account when a prospective occupant is looking at the terms and conditions of the lease. Then contrary to the case a few years ago, the occupants of commercial buildings are far more likely to look at the potential energy bills for a particular property when weighing up the cost per square foot; while occupying environmentally friendly premises can be an essential element to many organisations’ corporate sustainability policies. Achieving these multiple goals for refurbishment contracts - on time, within budget and defect free - requires a high level of expertise in terms of coordination from those running the contract. Only by employing an organisation with the relevant skill set and physical resources, which also focuses on communication up and down the supply chain, can clients expect to realise their ambitions.