In this roundtable, engineers discuss evolving automation standards for office buildings and where the industry is headed.
Automation insights
- Office building automation is increasingly focused on integrating building systems to reduce complexity, streamline operations and improve energy performance.
- Older office buildings present significant opportunities for efficiency upgrades through targeted control improvements and incentive-supported modernization, without full system replacement.
Respondents:
- Phil Beadle, PE, Senior Mechanical Engineer, HDR, Phoenix
- Thomas J. Fields, PE, LEED AP, HBDP, EBCP, Associate Principal, MG Engineering, D.P.C., New York
- Niki Fox, PE, LEED AP, Principal, Syska Hennessy Group, New York
- John Yoon, PE, LEED AP, Principal, McGuire Engineers Inc., Chicago
What mechanical, electrical, plumbing (MEP) or fire protection systems within office buildings require specialized automation or controls that previously might not have?
Thomas Fields: The new energy code(s) will be mandating occupancy controls for variable air volume (VAV) and similar systems. This will move toward additional integration with other systems such as lighting controls. To keep costs down and the user experience simplified, consolidation between control systems will need to become commonplace. A single sensor in an office should control lighting, heating, ventilation and air conditioning (HVAC), room scheduling and more. Engineers will need to drive the integration of these systems with lighting designers, technology consultants and end users.
Niki Fox: The integration of shades control into the lighting system.
John Yoon: ASHRAE Guideline 36: High Performance Sequences of Operation for HVAC Systems is an emerging guideline (not yet a standard) to pay attention to. Its intent is to improve energy efficiency and indoor air quality through use of consistent sequence of operation (SOO) for specific HVAC systems. It currently provides SOO guidance for VAV, hydronic, fan-coil units and rooftop units. Oddly, it does not yet have sequences for dedicated outdoor air systems (DOAS) or variable refrigerant flow systems. It is expected that those systems will be added to a future addendum. ASHRAE 36โs SOOs can seem unusually complicated compared to traditional SOOs. As such, not all building automation system (BAS) manufacturers are currently capable of fully implementing the recommended SOOs for every system type. This is expected to change as the industry becomes more familiar with its requirements.
Are you seeing automation and control features on these types of projects that you wouldnโt on other facilities?
Thomas Fields: One of the challenges in existing office buildings is having different control systems, some under landlord control and some under tenant control. Increasing communication between systems is an ongoing challenge that can reveal energy savings and better building operations.
John Yoon: While the temptation is to focus on cutting-edge building automation systems in new construction, existing buildings still represent low-hanging fruit as far as energy efficiency is concerned. Based on 2018 Commercial Buildings Energy Consumption Survey data, buildings constructed before 2000 represent 71% (68.6 billion square feet) of the total U.S. nonresidential building stock and a significant percentage of those older buildings still have pneumatic HVAC controls. Direct digital control (DDC) conversions represent a meaningful potential for energy savings but are often out of reach financially for building owners.
For budget-constrained projects in older existing office buildings with pneumatic controls, a DDC conversion using wireless pneumatic thermostats may make sense as opposed to a full DDC conversion. Utility companies will often provide significant incentives for these types of projects. This in combination with the reduced infrastructure costs associated with wireless controls could help enable projects that would not have been otherwise financially feasible. While exact requirements vary, the incentive requirements for the local utility company are:
โข Central time control for setback of space temperature.
โข Minimum setback space temperature of at least 8ยฐF in both heating and cooling mode.
โข Minimum setback period of more than 2,200 hours per year (compared to 8,760 total hours in a year).
โข Central control for interface for all thermostats to set the space temperature setpoints for both heating and cooling.
โข Manual override allowed but must be reset to central control setpoints after setback period.
โข Thermostat auto-calibration to eliminate drift.
While this level of functionality in DDC systems is commonplace, itโs something that is impractical with pneumatic controls. This gap in functionality is not just limited to HVAC automation, but indicative of numerous other systems in older buildings. This is something to keep in mind.
What automation and control features are being implemented with the specific goal of increasing productivity or comfort for employees?
Niki Fox: Dewpoint control.
John Yoon: Fully integrating room access, lighting, temperature and audio-visual controls together into a common platform is still relatively rare for office occupancies. However, that isnโt the case in the hospitality industry. In hotels, having the guest room seem personalized and responsive to the occupant goes a long way toward enhancing the โguest experienceโ and promoting brand loyalty. If a guest has experienced it before, hotels are often perceived as being lower quality if they donโt have that level of integration.
Those same integrated systems in hotels are also used to improve energy efficiency, track space utilization, optimize maintenance efforts and more โ all typical for office building BAS. While the technology used to enable that personalized functionality isnโt exotic, the question is why donโt we see more of it in commercial offices if itโs a simple expansion BAS capability? Trade jurisdiction issues aside, the real question is if that guest experience can translate over to an employee experience without seeming like intrusive company surveillance.
What smart or internet-enabled technologies are you being asked to specify to improve working conditions?
Niki Fox: Integration of occupancy sensors into the HVAC system for control beyond the thermostat level.
John Yoon: Weโre starting to see the proliferation of cloud-hosted building automation systems. Itโs not necessarily being used to improve working conditions, but to reduce reliance on local servers/software that are expensive to upgrade/expand and quick to obsolescence. The concept of โBAS as a serviceโ may seem attractive from an operational expenditure cost model standpoint, but it does have its downsides. First and foremost is security. Traditionally, we protect a BAS from cyberattacks by sandboxing it on its own network and firewalling it as best we can from the outside world.
With cloud-hosted BAS, we lose the ability to maintain that separation and have now created a new potential attack point that is outside our direct control somewhere on the cloud. If that remote hosting service is degraded, either accidentally or maliciously, how would the functionality of our BAS be impacted? While some vendors have solutions to this issue, itโs a good topic of conversation when evaluating any proposed system.
How have your engineers worked with building owners and facility managers to implement integrated technology in these structures?
Phil Beadle: The request for building controls remote network monitoring of new facilities is continually increasing. This includes controls engineering requirements in design and coordinating with existing network monitoring systems to ensure integration of new facility building management system โ a crucial component.
Building owners would like the ability to have 100% visibility of the building management system whether they are across the street or across the country. This means having secure, remote access with both reading and writing capabilities, enabling them to review alarms, change set points and troubleshoot control sequences.
This request for external access significantly increases the threat of cyberattacks, infiltration and the need to apply cybersecurity for any internet and cloud applications.
Niki Fox: Design and integration of separate operational technology (OT) networks.
What types of system integration and/or interoperability issues have you overcome for these projects and how did you do so?
Thomas Fields: One of the challenges in existing office buildings is having different control systems, some under landlord control and some under tenant control. Increasing communication between systems is an ongoing challenge that can reveal energy savings and better building operations.
Niki Fox: Getting a Master System Integrator onto the project to accelerate the schedule and minimize change orders.
John Yoon: A surprisingly common interoperability issue isnโt necessarily the hardware and software, but the contractors installing it. On larger projects, trade jurisdiction can become an issue. Contractors will claim โownershipโ of the systems that they install (such as lighting controls, BAS and fire alarms) but donโt necessarily emphasize coordinating potential scope gaps and/or overlaps with other contractors. Issues like figuring out who furnishes, wires and programs a given component that is shared by multiple systems are common. Often, these types of issues donโt manifest themselves until close to the end of the project when commissioning is about to start. This frequently ends up in finger pointing and change orders. Having a third-party system integrator who is focused solely on the integration process and coordinating the various contractors is often advisable.
Is your team using building information modeling (BIM) in conjunction with the architects, trades and owners to design a project?
Phil Beadle: Yes, the ability to virtually identify and resolve spatial conflicts is a fundamental reason why thearchitecture, engineering and construction industry has transitioned to digital design practices.
BIM is a process that uses 3D software to develop a model based on criteria that are important to the translation of the projectโs design. The 3D model is then used to review the project for quality control as well as provide the owner and stakeholders a visual means of providing input into the design process.
Autodesk Construction Cloud (formerly BIM 360) is a cloud-based document storage and collaboration platform that provides centralized team access to data for Revit projects, both internally and with external teaming partners.
Using digital models to assist in coordinating the design as part of the design review process allows early identification and mitigation of coordination issues between disciplines prior to construction. This also helps to reduce project costs and delays.
Design authoring tools are a first step toward BIM and the key is connecting the 3D model with a powerful database of properties, quantities, means and methods, cost and schedules.
Thomas Fields: Yes, BIM is an important tool used by all players on projects for coordination and streamlining construction.
Niki Fox: Yes, BIM is part of our daily work product.
John Yoon: Yes, using BIM is common. The ability to perform clash detection and 3D visualization are noteworthy benefits that traditional design tools donโt have. However, using BIM is often a challenge when working in existing facilities where the building geometry isnโt properly documented in the model.
When using traditional design tools, any level of uncertainty would usually result in a longer coordination process and the inclusion of an appropriate factor of safety as a contingency. However, visual detail in BIM models can unintentionally infer a level of precision that really isnโt there. That could encourage designers to have false confidence in the spatial information and design to tolerances that cannot be maintained. Clash detection and 3D visualization mean little if existing structural beams that you were trying to avoid were located at a different elevation.
What security and data privacy measures are integrated into the automation and control systems for office buildings?
Niki Fox: Cybersecurity plays a large role in the OT network.
How are cybersecurity concerns being addressed with building automation systems? What steps are you following with the building owner and operations team?
Niki Fox: We are writing measures into our Division 25: Integrated Automation specifications.
