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Going retro: to create "healthier" buildings

Atkins | 18 Feb 2015 | Comments

“Sick building syndrome” is not a recent concept. But the tactics being used to deal with the problem are breaking new ground while creating a more comfortable and energy efficient environment for everyone involved.

It’s well known that, for those who live and work in them every day, buildings can affect their health and wellbeing. The US Environmental Protection Agency (EPA) has a whole section of its website devoted to “sick building syndrome” symptoms and their possible causes.

For Dave McFarlane, senior technical director at Atkins in the US, the problem is straightforward: “Most buildings do not work,” he says. “As a matter of fact, I’ve been doing this for over 30 years and I’ve never walked through a building where everything was working.”

McFarlane has been involved with the National Environmental Balancing Bureau Building (NEBB) Systems Commissioning Committee since 2000 to help combat the problem. He helped to establish the national Retro-Commissioning procedural standards and processes for the design and operation of buildings to improve performance, lower energy use and drive down users’ complaints.

“Broadly, when I say ‘broken’, I mean the energy costs are unnecessarily high, and the temperatures or fresh air volumes can’t be controlled to a desired setting,” he explains. “These things result in people not being comfortable.”

The results can be felt in many ways. In the most extreme cases, significant health impacts have been observed, including autoimmune conditions brought on by poor ventilation, as well as asthma. Poorly regulated temperature and badly-lit offices have been found to adversely affect people’s concentration and reduce productivity. That’s not to mention the higher energy costs due to poorly maintained and inadequately operated heating and ventilation systems.

The growing awareness of the impact of indoor environmental quality on performance has come from two main sources – business and education. School authorities, designers, educators and builders across the world have been working towards constructing healthier buildings, with encouraging results. However, even for new buildings, there is no guarantee they will function properly, and in the existing stock of buildings, problems remain.

The causes behind underperforming buildings are numerous, but over the course of his work in designing and maintaining “healthy buildings,” McFarlane has identified five recurring components that tend to be found in buildings.

  1. Initial building designs that do not support comfort and efficiency. This can mean anything from using standards that are outdated or details that do not provide proper direction to the contractor, to specifying equipment or using control sequences that will not deliver the desired outcome. Sometimes the owner’s project requirements are not adequately defined. And some design firms use junior engineers who lack the practical experience in engineering, design, and building operations. This lack of experience – and the inability to see potential issues and work to correct them upfront – is a contributor to many issues.
  2. Contractors build systems that do not support comfort and efficiency. It’s a simple fact that many contractors do not understand the details and standards that are included in engineering documents. Additionally, there is pressure to deliver buildings in a fast-paced timeframe and at the lowest cost, which leads to flawed construction. The net effect is that contractors essentially build in guaranteed faults by not following the design documents.
  3. Complexity of equipment. It’s not just the systems that fail to meet the building’s particular needs, but also the use of equipment too complex for maintenance staff to properly operate. This almost guarantees operational problems as the maintenance staff make overly simplistic corrections to system operations to satisfy occupant complaints.
  4. Minimal and incomplete testing of installed systems. Typically the installed systems will be tested and measured by installing contractors on a cursory basis. The systems are never thoroughly tested and adjusted prior to owner occupancy.
  5. Maintenance of complex systems turned over to maintenance staff who have received minimal training. Again, this is a guaranteed problem built-in from the outset of the building’s life: when the systems are simply too complex for the average maintenance team to operate to an optimal level. Systems controls are often placed in override conditions to solve one problem and no longer function as intended.

Given all this, building owners and landlords see the flaws in their buildings and work to deploy solutions to the underlying problems, right? Not so, says McFarlane.

What people usually do if there is a problem, he says, is to adopt a service mentality of fixing one specific problem: “The service company will look around and ask, ‘Why is it too hot’? Then they will adjust one component and say, ‘We fixed this room.’ What they fail to do is look at the other contributing factors.

“Typically, a building owner may complain, ‘Our energy costs are too high, what can we do?’ An engineering or design firm will come in and focus specifically on design issues. They may identify the lighting source as the problem and decide to put in lower energy light fixtures; or decide they are going to put in a more efficient chiller, or improved insulation for instance, but they ignore operational issues. The industry in general neglects to look at the problem from a holistic standpoint.”

For McFarlane, the work focuses on designing a solution that not only addresses the underlying factors of the building’s poor performance, but also puts in place a plan to maintain the optimal environment going forward.

McFarlane cites the example of a building with 100 people, where ten complain. By definition, that wouldn’t qualify as a sick building, but in all likelihood, the maintenance team will try to do whatever they can to make those ten people happy.

“That means they will go in and tweak something. And that may work to solve that particular complaint, but the net effect is that they have just changed the energy use of the building or they’ve made somebody else, downstream, unhappy as a result.”

By trying to keep the building’s users happy on an ad-hoc basis – through small, incremental changes – the building ends up being thrown off its original design. Over time, the inefficiencies and problems will build, and so the cycle continues.

If the traditional remedies are failing to adequately address the problem, where does that leave building owners and tenants seeking more comfort, lower cost and greater energy efficiency? Can these embedded and longstanding deficiencies – many of which have been in place since the first bricks were laid – really be identified, analyzed and improved on?

McFarlane has taken on this challenge as part of his work with Atkins in the US. In his view, the key to successfully retro-commissioning existing buildings or commissioning new projects involves looking at building operations as a holistic system and not as a collection of separate interlocking parts.

“To truly understand what’s going wrong, you need to evaluate the current design requirements,” he says. “We will walk through a building and look at the walls, the windows, the glass, the lights, the number of occupants, and the equipment that must cope with that design.”

Once that process has been undertaken, Atkins will begin the effort to retroactively design the building to better align it to the current usage patterns. Then, Atkins’ technicians will go through the building and determine whether each element has been correctly configured and is operating for optimal performance. The review does not compare against the original design but looks at the way the building is currently being used.

“For example, let’s say, we find a room that needs 1,000 CFM of air and 55 degrees to cool it; we will look at what’s installed in the space and we look to make sure that the installation is done in a manner that will allow 1,000 CFM to flow into the room. If the room has changed, we may determine that the original design is never going to work because the room has changed and the original design is no longer valid. The space will need a different sized terminal box to deliver the right amount of air.”

It’s at this point that the Atkins process really begins to differ from other engineering firms. In the next step, Atkins will send in a team of diagnostic technicians that operate the equipment: raising or lower thermostats, changing set points on chillers and boilers to determine how the systems operate.

“They’ll test how the equipment runs, and if it’s not working properly, they will find the problem,” says McFarlane. “As we go through the building, we are making a list of contributing issues, which tells us what’s wrong and needs to be fixed.”

Atkins technicians will make some of the most obvious fixes right on the spot, or have the maintenance staff make minor repairs, so the owner will immediately see an improvement. In addition, if the on-site maintenance team isn’t able to carry out fixes as needed, Atkins will engage a contractor to visit the site and make the necessary changes as part of the project.

“After the contractor fixes the issue, Atkins will go back and make sure the corrective action was done properly, so that when we’re done, we know the building is set up to operate based on our design criteria. We set all the controls and adjust flows so that when we put the thermostat on 72 degrees, it will actually be 72 degrees in the room.”

So far, this retro-commissioning model has proved popular among US clients. A recent project at the Grand Forks County Office Building in North Dakota has exceeded the initial savings estimates on energy costs.

Because of improved temperature control and a new energy policy, occupant complaints have been reduced by 90 percent. As McFarlane says, “People don’t complain when they know that their space is being maintained within agreed upon temperature ranges.”

Central to retro-commissioning’s appeal is the paradox that while virtually every building has these problems in common, they also have the necessary conditions for a set of straightforward remedies.

“We’re not trying to sell somebody a new solar heating system, energy efficient boiler or other equipment. We are taking a standard engineering approach that redesigns the building to its current needs. We are testing systems and components and operating all equipment to ensure that they are capable of delivering the current needs of the building. We then fix, replace or upgrade equipment and systems as needed to provide a building that is operating at its current requirements,” McFarlane explains.

And this holistic concept, he says, is something that many engineering firms aren’t comfortable with.

“In many cases, architectural and engineering firms will design a project, write a report, and then it stops there. Our approach is to get hands-on and actually set the building up properly. We set up temperature control sequences and adjust air and water flows as required so we know it’s done right.”

Atkins has found that its approach to improved building performance will typically reduce energy use by 15 to 30 per cent with paybacks in one to five years.

“You’ll never win a race to be the cheapest firm in town, because another firm will cut corners, reduce scope and always beat you. You can win a race to be the best. You can control that. And when you’re the best, people will hire you because they know you’re the best, and then price is no longer the overriding factor. Our approach is based on proven engineering standards that delivers proven results.”

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