Signal Architecture
This pattern is shaped by
Problem
When the building envelope is designed for energy performance and the wireless network is designed for coverage, and neither designer talks to the other, the result is a building where the tightest, best-insulated rooms have the worst connectivity — and nobody understands why until the drywall is up.
Evidence and Discussion
Alexander designed for light and air with exquisite care — southern exposure, cross-ventilation, light on two sides of every room. He mapped the path of the sun through the building and shaped the walls to receive it. Wireless signal deserves the same deliberate attention, because the materials that make a high-performance envelope are precisely the materials that block it.
The conflict is specific and predictable. Foil-backed rigid insulation — the workhorse of passive house retrofits — attenuates WiFi signal by 30–50 dB, enough to create a near-total barrier. Metal cladding, wire mesh in plaster, concrete floor slabs (10–15 dB each), even low-e coatings on high-performance windows — all the things that make BUILDING ENVELOPE AS CLIMATE SYSTEM (275) work make wireless coverage fail. As buildings get tighter, they accidentally become Faraday cages. The home office behind two insulated walls has excellent thermal performance and no usable signal.
The solution is not maximum signal everywhere — that contradicts THE QUIET ZONE (262), where mass deliberately attenuates connectivity. The solution is *intention*: strong signal where people work and communicate, weak signal where people rest and gather, and no accidental dead zones caused by material choices nobody thought through.
This requires mapping the wireless environment at the same stage of design as the thermal environment — during material selection and wall assembly design, not after construction. Where will the router sit? Which walls use foil-backed insulation (signal barrier) and which use mineral wool (signal-transparent)? Where does ethernet run to eliminate wireless dependency at fixed workstations? The answers shape the wall sections, the insulation specifications, and the wiring plan. They cannot be retrofitted without tearing open walls.
Therefore
when designing a building, map the wireless coverage as deliberately as you map the natural light. During envelope design, identify which wall and ceiling assemblies will block signal (foil-faced insulation, metal cladding, concrete, wire mesh) and which will transmit it (mineral wool, wood, fibreglass). Place the router centrally in the working zone, with signal-transparent assemblies between it and the spaces that need coverage. Use signal-blocking assemblies deliberately toward sleeping and rest spaces. Run hardwired ethernet to every fixed workstation and to the router's location, so the wireless network serves mobile devices, not the primary work connection. The building's energy envelope and its signal envelope are drawn on the same wall section — design them together.