As time goes by, everything ages and buildings are no exception. From the minute a building is completed, wear and tear commences. As the years go by, buildings and their systems deteriorate and are subject to degradation resulting in more frequent breakdowns causing decreased efficiency, tenant discomfort and of course, higher energy bills.
The question is, at what stage of life is your building? Is it functioning efficiently or is some work required? If so, what needs to be carried out and how will it be done? Here we look at commissioning, recommissioning, and retro commissioning regarding building systems, particularly the concept of retro commissioning and HVAC systems.
Commissioning, Recommissioning and Retro Commissioning
Firstly, let’s look at what these are.
Commissioning
This is defined as the process of ensuring that a building’s operating systems, mechanical, electrical, HVAC and any others are designed, installed and programmed for optimal performance.
Ideally, commissioning is used for new buildings or new system installations. It ensures that equipment is appropriately sized for its purpose, correctly installed and calibrated for peak performance and energy consumption and savings. During construction and system installation, the commissioning team conducts quality checks to ensure that the design specs are being fulfilled and recommends any amendments required. This ensures that equipment will fulfil the design functions.
For example, HVAC systems, to be optimally efficient, require advanced control strategies that are designed early in the design and construction process.
Recommissioning
This process takes place after a building has become operational. Tenants have moved in, systems have been commissioned, but it is found that systems are not performing as required.
For example, the HVAC system may be underperforming and requires additional data points and reprogramming or, there are faulty components. Facilities managers and owners may not realise what is required until the building has been operational for some time. Recommissioning is utilised for buildings that have been in use and need optimising, or where owners want green energy solutions for existing systems.
Retro Commissioning
Retro Commissioning is a process of increasing cost savings and improving energy savings for buildings that have not been correctly commissioned in the first place.
This process would probably be required in old buildings with longer life spans that have been modified over time or not commissioned when built or when additions were made. This process involves assessing the building’s systems accounting for their original design specifications and changes to use and occupancy since construction. The process, when completed successfully, brings the building up to modern standards and regulations.
Benefits of Retro Commissioning
One of the most important benefits of retro commissioning is cost savings. According to the Environmental Protection Agency in America, the average retro commissioning project yields a 15% reduction in energy consumption and with rising energy prices that is significant. In the long run, retro commissioning reduces maintenance costs as the systems are now fit for purpose.
Retro-commissioning improves the HVAC system through boosting air quality by ensuring sufficient fresh air intake, reduces moisture and could even improve property value.
Buildings account for 33% of worldwide energy consumption and emissions so it makes sense to retro commission buildings to make them greener and more sustainable which in the modern business environment is highly desirable.
Building Retro Commissioning
Retro commissioning tackles many of the complex systems in buildings.
HVAC
Retro commissioning of the HVAC system can bring many problems to light. Is the system still fit for purpose If so, is it performing optimally with acceptable maintenance costs? Is it using excessive energy?
A complete HVAC system audit is part of retro commissioning. The inspection can include inspecting air economisers and demand-controlled ventilation for proper function. It can also check for blocked air registers, broken exhaust fans and whether the HVAC equipment complies with building occupancy codes. This process may reveal broken machinery or inefficiencies that waste energy, reduce occupant comfort and harm indoor air quality.
The entire system can be evaluated, recommendations made, budgets drawn up and decisions made on the future.
Lighting and Lighting Control
With low energy lighting being introduced several years ago, it’s probable that no old, energy greedy light bulbs remain in use, but depending on the age of the installation, it may be worth checking. The retro commissioning team can evaluate the lighting needs of the various spaces in the building and determine if the lighting is still fit for purpose. Smart lighting systems, occupancy sensors and automatic lighting should be considered.
Humidity Control
Humidity plays a strong part in occupancy comfort levels. Retro commissioning the system ensures it will function as desired, preventing mould, dampness and the associated health problems of occupants and reducing maintenance costs.
Sprinkler and Fire Prevention Systems
Fire prevention is a statutory requirement and should form part of a retro commissioning process. Modern BMS systems often incorporate firefighting and alarm systems.
Retro Commissioning Process
The process usually consists of five steps.
Planning
This consists of pre-screening the building for energy use, HVAC and tenant complaints. From this data a plan can be developed.
Detailed Investigation
Diagnostic tests and monitoring are carried out to examine the building’s energy performance and operations. Detailed documents and reviews are then prepared. At this stage it would be wise to present a budget.
Implementation
On approval, the necessary improvements and repairs from the investigation are carried out.
Confirmation
A full retro commissioning report on the work undertaken is produced for the relevant stakeholders.
Training
Any necessary training is given on the upgrades. This may range from full BMS training to routine maintenance of equipment.
Retro commissioning is a suitable process to reduce energy usage and meet efficiency targets as well as improving occupant comfort and extending the life of a building. As buildings age and the drive to more sustainable living speeds up, it is more important than ever to breathe new life and better air into existing buildings and facilities.
Whether commissioning, recommissioning or retro commissioning, ACS has a range of products and services to make your project run smoothly. We supply products from world leaders in their industries including HVAC supplies, building management systems and training and peripherals, lighting and lighting controls and a full range of sensors and transmitters.
Contact us to discuss your needs.
