Corporate office space has transformed in recent years. Traditionally, these spaces included a ring of private offices around the perimeter of the space, with cubical farms occupying the center. Today, more companies have an open office plan, which requires different considerations for HVAC system design.
Most of those perimeter offices are disappearing, as companies want space that takes advantage of natural light. And the cubicles are being replaced with workspaces designed for specific types of activity, such as pods for quiet concentration and team lounges for collaboration. How does all this change impact HVAC system design? Read on for some important strategies.
HVAC system design strategies for better comfort in an open office space
In general, we can’t emphasize enough the importance of thinking about HVAC system design early in the planning stages of the renovation or build project. The following are essential strategies that must be taken into consideration early, or you’ll end up needing to make expensive changes down the road.
1. Design the space to reduce HVAC cooling loads for energy efficiency
The HVAC system consumes more energy than any other part of your office space. When you’re renovating or building a new open plan space, it pays to design the space to reduce HVAC loads and save on energy costs. You’ll probably be installing better insulated walls, floors and windows, but here are some additional ideas you may not have considered.
Adding more daylight is a design consideration that’s great for workplace health and wellbeing, and also for reducing heating loads in the winter. However, to avoid solar gain and increased cooling loads in the summer, consider using tinted low-e glass.
Another energy-saving idea is lighting systems that dim or turn off when there is sufficient daylight for working in the space. This strategy combined with cooler types of lighting produce less heat waste and reduce the cooling load on your HVAC system.
2. Size your HVAC system correctly
Calculating loads for HVAC system design must take into consideration all your energy efficiency design features in order to avoid installing an oversized HVAC system.
If you’re not an HVAC expert, here’s something you may not realize: bigger is not better when it comes to HVAC system design. Installing air conditioning equipment that’s oversized for the required load of your space will produce inadequate comfort conditions. Here’s what happens: the system is constantly turning on and off, and never runs long enough to remove humidity. So your space is clammy and riddled with hot and cold spots.
To properly calculate load requirements in planning your HVAC system design, it’s essential to consider more than square footage. Computer simulation tools are necessary to account for building materials used, daylight, lighting design, and space activity patterns that impact heating and cooling loads. This is one reason it’s essential that the design team consults with HVAC experts early in the design process.
3. Create zones
For better energy efficiency as well as comfort, your HVAC system design should include multiple independently-controlled zones within the space. That’s because, even in an open office, different areas have different requirements to remain consistently comfortable. For example:
- Perimeter spaces are more affected by weather than interior areas and should be controlled separately
- Some spaces have special needs for temperature and/or humidity control, such as computer rooms from comfort zones, and these must be controlled independently.
- Areas where large numbers of people are gathering, such as big conference rooms, will need more cooling when in use, and less when unoccupied.
This can be easier said than done in an open office space that doesn’t have many traditional walls, and it’s another reason not to skip HVAC system design expertise in your plans.
Here’s some additional information about HVAC technology that works particularly well for zoned office spaces: 7 Reasons to Choose VRF HVAC Technology for Your New Air Conditioning
4. Take advantage of sensors
Sensor technology for smart buildings has come a long way in recent years. Two types of sensors are useful for saving energy by integrating with HVAC system design:
Light sensors are mentioned above: they can sense the amount of daylight available in the space, and adjust the lighting as needed. These sensors can be tied into HVAC system design to adjust the heating and cooling accordingly as well.
Occupancy sensors track how many people are using the space at any given time, and can send messages to HVAC controls. For example, when sensors detect that a large meeting space is in use, cooling can be increased to accommodate the increased load in the area.
5. Consider under floor air distribution
Traditionally, office spaces have been cooled with overhead air distribution. However, this HVAC system design can be less than effective (and less energy efficient) in open, modern office spaces with high ceilings.
Instead, many office spaces with an open plan are using under floor air distribution systems. These systems use diffusers installed under a raised floor to deliver conditioned air to different areas within the space. The systems then take advantage of stratification that moved warm air up toward the ceiling to be replaced by the cooler conditioned air at workers’ feet. Under floor air is great for providing consistent comfort levels as well as maintaining indoor air quality.
6. Address indoor air quality with ventilation
When it comes to the right HVAC system design for a modern office space, it’s not only about thermal comfort. It’s just as important to control humidity, eliminate odors, and remove contaminants such as dust, carbon dioxide and even bacteria and viruses that can spread illness. Maintaining proper indoor air quality levels is important for workforce wellbeing and productivity.
With a pandemic raging around the world, that has never been more critical.
That means addressing the “V” in HVAC: ventilation. Your HVAC system design must provide for adequate intake and distribution of outside air within the space, as well as well-controlled distribution of conditioned air. This is another are where the expertise of HVAC design professionals makes the difference between getting everything right before building, and having expensive problems to fix later.
To learn more about HVAC technology and tactics for COVID mitigation (including ventilation design), download our informative guide.
Trust HVAC system design to the experts
Even besides the strategies for open office design that are covered here, there are even more reasons to make sure you get an expert HVAC design consultation and plan early in your renovation or build project. Find out more from this related article: Skipping Commercial HVAC Design Could Sabotage Your Renovation.
If you are in the planning stages of a modern office build or renovation (especially in an urban setting), learn about choosing the right HVAC systems for office space from this informative reference: The Ultimate Guide to NYC Light Commercial Air Conditioning.