Commercial & Multi-Family Radon in Denver, CO

Same Physics, Different Building

Soil gas behaves identically under a school and under a bungalow. Everything around it changes. A commercial or multi-family building has a mechanical ventilation system moving large volumes of air on a schedule, several separately controlled zones, a slab far too large for one suction point, and a set of people who need the results who are not the people who occupy the space. None of that alters what radon is. All of it alters how you measure it and how you fix it.

Placement Scales With Floor Area, Not Rooms

Residential testing asks which room is the lowest lived-in level. Large-building protocols ask how much ground-contact floor area there is, and place devices across all of it — in every frequently occupied ground-contact room, rather than in a representative sample. That is normally many more monitors than an owner expects, and it is where budgets get trimmed and results get ruined. A building-wide average built from too few placements will happily hide one hot wing, and the hot wing is the entire point of testing.

The Ventilation System Is Part of the Problem

A building's HVAC can help or hurt. Run at positive pressure relative to the ground it can suppress soil gas entry; run at negative pressure — economiser cycles, unbalanced exhaust, a kitchen or lab hood pulling hard — it drags soil gas in far more aggressively than any house ever would. Because those modes change with the season and the schedule, testing has to reflect how the building is actually operated, and mitigation design has to be coordinated with whoever controls it rather than bolted on beside it.

Multiple Suction Fields

Large slabs are usually poured in sections, with footings and grade beams between them that a single fan cannot pull across. In practice that means several suction points and often several fans, each holding a defined area, sized from a diagnostic rather than from a rule of thumb. It is the same principle as a residential system repeated across a floor plate, and the design work is a larger share of the job than the installation is.

Reporting, Scheduling and Who Reads It

A property manager, a board, a tenant and sometimes a lender all need something from the same result, and they need different things. We plan the reporting for that at the start instead of issuing a homeowner report and translating it afterwards. Scheduling gets the same treatment: testing is unobtrusive, but core drilling a slab is loud, and in an occupied building that conversation belongs before the quote. Post-installation testing follows commissioning, on the same expanded placement plan as the original survey.

How long does it take? Depends entirely on ground-floor area and how many suction fields the slab turns out to need. Scoping is its own visit, and we say so rather than quoting blind.

Questions People Ask First