In the homes we work on, the mechanical room is closer to a small commercial building than to a residential closet. Multiple boilers, multiple chillers, hydronic loops on radiant slabs, snow-melt zones, geothermal wells, ERVs, dedicated outdoor air, multi-stage humidification. The climate plant is the most expensive and most invisible system in the residence, and it does not respond well to off-the-shelf wall thermostats.
We design and programme HVAC controls at the level of seriousness the plant actually requires — native DDC (direct digital control) on Reliable Controls primarily, Tekmar for radiant and snow-melt where it fits, and integrated cleanly into the Crestron and Lutron systems above them. The household sees a single climate vocabulary; the plant runs on the right tool for each job.
Most residences in North America run perfectly well on a Nest, a Honeywell, or a Crestron Home thermostat module wired to a conventional rooftop unit. That is the right answer for the majority of the market. The threshold at which DDC becomes the architecturally correct choice is narrower than the industry pretends — and clearer than most owners realise.
Two or more boilers, two or more chillers, a primary-secondary hydronic distribution, three or more air handlers, ERVs in series, dedicated outdoor air. At this scale a thermostat is no longer in control of the building; the plant is, and it needs a control system that can read it.
Radiant slabs, snow-melt zones, hydronic towel warmers, pool and spa heat exchange, geothermal manifolds. The residence is moving water through the building, not just air, and the controls have to balance many circuits against each other and against the outdoor reset curve.
BACnet on the equipment, Modbus on the boilers, RS-485 on the older panels, KNX or LON from a European installation, and the homeowner-facing surface on Crestron or Lutron above all of it. A residential thermostat doesn’t speak any of these. A DDC system speaks all of them natively.
DDC is not just a fancier thermostat. It is a small fleet of programmable controllers, one near each piece of equipment, talking to one another over the building’s control network. Each controller is programmed by hand for the specific equipment it serves, with logic written against the residence’s actual operating profile.
The outdoor reset curve. The hydronic loop temperatures shift continuously with the outdoor air temperature, tuned against the residence’s specific thermal envelope and the seasonal pattern of occupancy. The slab in the master suite never goes below 70°F when the principal is in residence; it can ride at 62°F when the household is in Aspen for the month. The reset curve is written by hand against the property.
Demand-driven primary plant. Boilers and chillers stage on and off against actual hydronic load rather than a fixed schedule. A single boiler in mid-season, two boilers on the coldest mornings, four boilers cascading into snow-melt during a winter storm. The plant uses what it needs, when it needs it.
Cross-system orchestration. When the household wakes the residence at 6 a.m., the DDC controllers prime the slab thirty minutes ahead, the air handlers spool up against outdoor air temperature, the ERVs ramp to the morning ventilation rate, and the Crestron scene engine fades the bedroom lights and lifts the shades. One household intent; four systems acting in concert.
Continuous commissioning. The DDC system records every setpoint, every override, every valve position, every alarm. The data feeds Intuitiv AI which reads it daily and surfaces what the plant is telling us — before the principal does.
Two control systems carry almost every residence we work on. Each is the right tool for the layer it serves. We design and programme on both natively, by the senior engineer attached to the property.
Native DDC for the residence’s mechanical plant. MACH-Pro controllers on each piece of equipment, MACH-System for the operator interface, and a control vocabulary written by hand against the residence’s actual operating profile. We are an authorized Reliable Controls integrator through our sister company, Wenner Group — the Reliable Controls factory is in Victoria, the same city as the studio. More on Reliable Controls →
Tekmar is specified on residences where the hydronic layer is large enough to warrant its own zone-by-zone control intelligence: radiant slabs across multiple wings, snow-melt across long approaches and walkways, hydronic towel warmers and pool circuits integrated with the primary heating loop. Tekmar reports up to the Reliable Controls layer and ultimately to the household-facing Crestron surface. More on Tekmar →
DDC sits underneath Crestron and Lutron in the residence’s system architecture. The household never touches it directly. They touch the Tahoe panel in the hallway, the iPhone app, or the keypad in the master suite — and the DDC system answers underneath, in the language each piece of mechanical plant understands.
The integration happens at the BACnet layer. Reliable Controls speaks BACnet/IP and BACnet/MSTP natively; Crestron speaks BACnet through its native module. We bridge the two cleanly, so a household command (“Goodnight”) lands as an intent on Crestron, gets translated into climate state changes on Reliable Controls, propagates to the Tekmar zone controllers, and the residence behaves as one vocabulary — never as four disconnected systems.
This is the layer at which most residential HVAC installations fail. A regional dealer specifies a thermostat; the architect specifies a radiant slab; the boiler installer specifies a boiler-reset controller; and the four pieces of equipment never speak to one another. The household feels it as a system that almost works. The fix is always the same: one DDC system above the plant, programmed natively against the residence’s actual operating profile, integrated cleanly into the household-facing control system.
The questions that come up most often when households, architects, and mechanical engineers first reach a conversation about advanced HVAC controls.
When the mechanical plant has more than one boiler, more than one chiller, hydronic distribution, radiant slabs, snow-melt, or geothermal wells. Below that threshold a Crestron-driven thermostat layer is enough. Above it, DDC is the architecturally correct answer — not a luxury, a necessity.
Reliable Controls, primarily — we are an authorized integrator through our sister company, Wenner Group, and the factory is in our home city. For specific subsystems (radiant, snow-melt, hydronic) Tekmar is often the right specialist tool, reporting up to Reliable Controls.
Yes, natively, over BACnet. We programme the integration at the scene engine level so a household command lands as one intent and propagates to every system. The household touches a single vocabulary; the plant underneath uses the right protocol for each piece of equipment.
Always. We are a controls specialist, not a mechanical engineer. The MEP firm designs the plant; we design the control layer above it, in coordination. The MEP’s sequence of operations becomes our programming brief.
Frequently — this is a substantial portion of our DDC engagements. We audit the existing code, write a remediation plan, and either work alongside the original installer or take over the engagement. The first survey is usually free; the remediation plan is a paid deliverable that the household owns.
Reliable Controls and Tekmar both emit rich telemetry. Intuitiv AI reads it, learns the seasonal pattern of the residence, and surfaces drift before it becomes a phone call. A stuck valve, a damper that’s lost calibration, an ERV running outside its normal envelope — the platform sees it days before the household feels it.
A short, written brief is enough to begin. If the residence has DDC in scope (or should, and doesn’t yet) we respond personally, within two business days.
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