This article continues our multi-part series focused on architectural coordination as it relates to MEP systems, based on changes to the International Building Code and related standards for the 2021 code cycle. Today we address a significant and growing challenge impacting both emergency and non-emergency communication systems—specifically how modern energy-efficient building envelopes are degrading radio-frequency (RF) signal performance, with major implications for system design and coordination.
Impact of Energy-Efficient Building Envelopes
Over the past several code cycles, energy efficiency standards such as the IECC and ASHRAE 90.1 have pushed buildings toward tighter, better-insulated envelopes. These high-performance assemblies typically include continuous air barriers, thick insulation, and Low-E multi-pane glazing, along with an emphasis on eliminating uncontrolled air and thermal leakage.
While these improvements dramatically enhance building energy performance, they also act as barriers to radio-frequency signals. Dense construction materials—including concrete, steel framing, foil-faced sheathing, and insulated glass—can significantly attenuate or altogether block signals from both public safety radios, affecting firefighter, police, and EMT communication within the building, as well as commercial cellular networks.
Growing Requirements for Emergency Responder Radio Communication Systems (ERRCS)
As building envelopes become more energy efficient, the likelihood of needing an ERRCS increases—even in locations where external radio coverage is strong. Because current construction methods are inadvertently killing RF signals, the IBC and IFC have added explicit requirements to test buildings for signal strength before and after construction, and require installation of an ERRCS system if post-construction signal strength is below baseline levels. ERRCS systems typically include a rooftop donor antenna, distributed antennas throughout the building, a dedicated radio amplifier head-end, and independent battery backup. These systems must often be routed through corridors, mechanical shafts, or ceiling spaces, requiring careful architectural and MEP coordination.
Growing Need for Cellular Booster Systems
Energy-efficient construction techniques not only impact public safety radio systems but also impair commercial cellular coverage within buildings. Where cellular coverage is inadequate, owners are increasingly required to install distributed antenna systems (DAS) or cellular booster systems to extend carrier signals throughout the building. These booster systems require rooftop donor antennas, internal cabling, and distributed interior antennas—similar to ERRCS, but often serving multiple carriers (Verizon, AT&T, T-Mobile) and user devices.
Cell booster planning must consider space for head-end equipment, backup power integration, and signal distribution pathways through finished spaces. Unlike ERRCS systems, cell booster systems are not typically code required, but are often desired where indoor cell coverage is poor, as building occupants expect seamless mobile connectivity for their daily use.
Impact on System Monitoring and Remote Maintenance
Beyond public safety and personal connectivity, degraded cellular signals also impact critical building system monitoring and maintenance functions. Many fire alarm systems, elevators, HVAC controls, and energy management platforms now rely on cellular modems as their primary or secondary communication path.
Fire alarm monitoring, in particular, has shifted heavily toward cellular-based reporting in lieu of traditional copper phone lines. Similarly, elevator trouble signals and HVAC service alerts increasingly use wireless reporting to vendor apps or service portals. Without reliable internal cellular coverage, these systems cannot maintain active monitoring, potentially impacting code compliance and delaying occupancy approvals.
Poor signal quality can force last-minute system redesigns, including the addition of booster panels, wireless gateways, and reprogramming of communication paths. Early planning does not change the need for additional systems, but can minimize the architectural and construction timeline impact.
Early Planning is Essential
Tighter building envelopes are improving energy performance and operational efficiency, but are creating new and significant challenges for emergency communications, occupant connectivity, and system monitoring.
Architects, engineers, and owners must now recognize that RF coverage is an essential part of a building’s infrastructure, not just a service afterthought. Bringing ERRCS planning, cellular booster infrastructure, and signal quality discussions into schematic design phases is the best way to avoid costly late-phase redesigns, change orders, occupancy delays, and project budget surprises.
If you’d like to see how Barton can support the planning phase of your project, give us a call or send an email. For questions about this or other technical topics, please contact Wes Stiles, PE, Director of Electrical Engineering at 717-845-7654 or wls@ba-inc.com with questions about any items covered in this article.