The benefits of using wireless technology with BAS jump out in retrofit projects. It’s fairly easy to understand how eliminating the need to run wire, and potentially, conduit in an existing facility (where walls and ceilings are closed and tenants are already occupying the space) is beneficial. But what about using wireless for new construction projects? Does wireless provide tangible benefits in projects where running wire may not be that difficult because walls and ceilings are still open and tenants have yet to move in?

The answer is an emphatic yes. Although not all of the benefits for using wireless in a retrofit project may exist, new construction projects do present unique challenges that wireless technology can help resolve.

One major benefit that wireless can bring to new construction projects is the elimination of the traditional dependencies that exist between trades — that is, work must always occur serially. For example, consider the installation of a wired room temperature sensor. First, the wall must be erected by a trade, then the electrical box installed (and conduit run if required), and the wire pulled by an electrician, and then, sometime later, the device is installed and commissioning completed by the technician.

Wireless technologies allow an electrician to simply mount a wireless room temperature sensor on the wall when it’s finished, and (other than any configuration requirements that might be required) the job is complete. The other potential scenario is that the sensor is temporarily mounted until the final mounting location is determined and then simply moved.

Almost all the required coordination between the various trades is eliminated. This cancels the complexities of multiple trades waiting on each other to finish their individual tasks. So projects proceed more efficiently and spaces are ready sooner for potential tenants.

Streamlining the process

Inevitably, there are issues on the project that delay the construction process or cause out-of-sequence work that negatively affects the schedule. Because final commissioning of the BAS is completed at the end of the project, these delays end up compressing the commissioning schedule. However, because wireless technologies can allow a BAS to be brought online significantly sooner, earlier delays may not have as big an impact on final commissioning of the BAS.

Another area where wireless offers benefits to new construction projects occurs when BAS controls are factory-mounted by the terminal box manufacturer. After being installed by the mechanical contractor and then powered by the electrician, the controls can come online and automatically establish communication with their supervisory controller. Wireless mesh networking technology is enabling this today. Network IDs and other configuration information can be set either at the factory or by the electrician when the controls are wired and powered. Troubleshooting and commissioning can be done by exception, eliminating the need for a technician to travel to each terminal box. The result? A streamlined commissioning process and a system on-line sooner, rather than later.

Wireless technologies are also more forgiving when it comes to design errors that often crop up in new construction projects. For example, achieving the optimal placement of a room temperature sensor is always a challenge. In a newly constructed facility, the sensor location is selected during the design. Oftentimes, only after the facility is built does it become readily apparent that the location is flawed. It is difficult to envision the optimal placement of all sensors for control and comfort, plus coordinate with interior walls and furniture during the design phase.

When the space is complete and the optimal sensor location determined to be different than the original design, relocation of the sensor is now a costly proposition, requiring walls to be opened up and new wiring installed. That is, if you are lucky enough to not have to deal with concrete or cinderblock walls, where moving a room sensor may not even be an option. Also don’t forget the additional cost of the dirt and disruption to tenants who might now be in the space, which also makes this undesirable. It’s easy to understand that a wireless room sensor can easily be relocated after construction is finished without having to deal with these potential problems and issues.

Although wireless technology provides some unique benefits to new construction projects, it also provides some unique challenges and considerations that don’t exist in retrofit projects.

An important one is the inability for an engineer to conduct a site survey to ensure that the facility is a good fit for wireless technology. One obviously can’t go to a facility that hasn’t been built and place radios around the facility to gauge how well wireless communications will work in a specific facility. With new construction projects, you have to review the information available and try to reach such conclusions independently.

Depending on where in the project schedule you are, this information may include only a general floor layout and a description of building materials. However, with the experience gained from more and more installations, adhering to rules of thumb should guide the installation well and be the only criteria required to ensure successful implementation.

It’s clear that the use of new wireless technologies, including wireless mesh communications, for building automation is gaining acceptance in the market. Their value is not only evident in retrofit projects, but new construction projects as well. Wireless devices allow considerable flexibility in the installation and commissioning of building automation controllers and sensors. This allows BAS to be installed and brought online faster and avoids costly delays and cost overruns. All benefit in the end. IBT