Is the HVAC sector producing truly sustainable buildings? Well, the truth lies somewhere between the rhetoric and the reality.
The rhetoric praises the virtues of green engineering. Solar power, photovoltaics, biomass and ground source heat pumps are the usual suspects from an ever-growing list of earth-saving technologies, the predicted savings from which are banked by clients and project teams long before they’re switched on.
The reality, which usually starts to show a few months after completion, often brings the rhetoric down to earth with a bump.
Systematic post-occupancy evaluation tends to highlight some pretty big credibility gaps. The major ones are excessive energy use and occupant dis-satisfaction with comfort and building usability.
The core of the problem stems from a failure to manage expectations - of design team members as well as those of the client - throughout the procurement process.
So how can we close the credibility gaps? Primarily, there needs to be a recognition that buildings are not operationally ready at practical completion.
It’s in no one’s interest to persist with forms of contract that encourage project teams to disband after handover. Buildings with complex building services (or advanced passive features) need a lot of fine tuning, not just resolution of defects.
But once project team members have moved on to other jobs, they are unable to provide that support.
Buildings subsequently under-perform, while the construction industry fails to see the problems and doesn’t learn from experience.
Perhaps the best way forward lies with a process known as Soft Landings. In essence, Soft Landings is a set of procedures for graduated handover that can last for up to three years following occupation.
The work steps in the Soft Landings Framework, published by BSRIA, are geared towards ensuring that the quality and functionality of new and refurbished buildings is achieved in reality. It’s all about closing the loop between design aspiration and operational outcomes, and achieving the best environmental performance that we all seek.
Stage by stage
Soft Landings starts with requiring greater clarity at the inception and briefing stages about client needs and required outcomes. The design stage can proceed much as usual, but with greater attention to applying the procedures established in the briefing stage.
As design develops, the performance predictions need to be regularly reviewed against the original expectations. Any differences need to be resolved or explained as they emerge.
Soft Landings places greater emphasis on building readiness, with the designers and constructors having greater involvement during the pre-handover and commissioning stages.
A Soft Landings team is required to be located on site during the users’ initial settling-in period, with key project professionals involved after occupation, during and beyond the defects liability period to resolve outstanding issues. These paid duties can extend for three years after completion.
Three years aftercare might sound daunting - and costly - but it can drop off quite steeply the faster a building’s performance can get to truly meeting the client’s requirements and design targets.
There is no reason why this can’t be achieved after 12 months fine tuning. In any case, the cost of the additional professional duties and formal post-occupation evaluation need to be considered against the cost of excessive energy consumption, which often cannot be reined in.
Soft Landings should also lead to less costly re-work for design teams and contractors, who often employ specialists to clear up poorly completed work.
Soft Landings shifts the emphasis for good performance away from just design aspiration to the way buildings are actually managed and maintained. This dovetails with moves towards energy performance certification, building logbooks, green leases and corporate social responsibility in property development.
The purpose of Soft Landings is to creates virtuous circles for all. It offers the best hope for truly integrated and robust design. In a climate-challenged world, only the best buildings deserve to survive.
Roderic Bunn is a building analyst for BSRIA