For builders, electrical contractors, and energy raters.
The blower-door test has quietly become one of the most consequential moments in a new home's life. Under the prescriptive path of the 2021 IECC, a home in climate zones 3 through 8 has to come in at or below 3.0 ACH50 to pass — and that line is now the gate in most of the country. Miss it, and you are chasing leaks late in the build, on the clock, with the cleaning crew already scheduled.
Here is the part that does not get said often enough: most of those leaks are penetrations. Every hole drilled through an exterior wall for a wire, every box cut into the air barrier, is a place air can move. The tighter the code gets, the more each one counts.
This raised a question worth asking with real data: if a home uses fewer wires in the walls, is it measurably tighter?
The question we put to an independent firm
Levven's Switched Right® system is wire-free by design. Switches talk to a power controller wirelessly, which means the runs of wire and the boxes that a conventional switching layout puts into exterior walls simply are not there. Fewer penetrations, in theory, means a more continuous air barrier.
To find out whether that theory shows up in the field, we commissioned Ekotrope, a building-energy analytics firm, to look at the numbers independently. The study drew on a sample of roughly 2,000 rated homes with verified, blower-door-tested ACH50 results. Ekotrope matched homes built with Levven products against a control group of comparable homes built without them — same market, single-family detached, similar floor area and energy-performance range — and, because air-tightness behaves differently across stories, split the comparison into one-story and two-story cohorts.
What the data showed
In every comparison, the Levven cohort came in tighter.
Cohort | Group | Mediam ACH50 | Mean ACH50 |
One story | Levven | 1.76 | 1.85 |
One story | Traditionally wired | 1.95 | 1.97 |
Two story | Levven | 2.09 | 2.11 |
Two story | Traditionally wired | 2.50 | 2.19 |
-10%
lower median air leakage, one-story homes
-16%
lower median air leakage, two-story homes
Lower is tighter. Levven posted the lower value in all four comparisons.
The clearest signal is in the one-story homes, where the sample is largest, and the result is consistent on both median and mean: Levven homes came in around 0.1 to 0.2 ACH50 tighter than their matched peers. The two-story homes pointed in the same direction.
To be clear about scale: both groups comfortably cleared the 3.0 ACH50 line. The difference is the margin. In a world where the code keeps tightening, and the test is pass/fail on the day, a tighter starting point is a room you do not have to fight for at the end.
The likely reason: fewer holes in the air barrier
The mechanism is not mysterious. A conventional switching layout puts conductors and boxes into walls, including exterior walls, and each one is a penetration that has to be sealed and detailed correctly to keep the envelope tight. A wire-free layout removes a meaningful share of those penetrations before anyone reaches for a tube of sealant. Fewer penetrations is a more continuous air barrier, and a more continuous air barrier is a lower ACH50.
That is the most plausible explanation for what the data shows — and it is the same logic builders and raters already apply when they hunt down leaks one penetration at a time.
An honest note on what this is — and isn't
This analysis shows an association, not causation. It does not prove that installing Levven products will lower any individual home's ACH50, and Ekotrope was clear about that limitation. What it does show is a consistent, real-world pattern across a large sample of independently rated homes: the homes built with Levven were the tighter ones, every time the data was sliced.
We would rather tell you exactly that than oversell it.
What it means if you build or wire homes
- Fewer penetrations to detail and seal. Every box and conductor you do not run through an exterior wall is one less spot to air-seal correctly — and one less thing to fail on test day.
- More margin under the code line. As jurisdictions tighten toward and below 3.0 ACH50, a tighter baseline is cheaper than a late-stage scramble.
- One less variable on a high-stakes test. The blower-door result is increasingly the difference between a certificate of occupancy and a callback. A more continuous envelope is a more predictable one.
Tighter homes are also better homes for the people who live in them — lower utility bills, fewer drafts, steadier comfort. But for the people who build and wire them, the practical story is simpler: fewer holes, more margin, a more predictable test.
The figures above are drawn from an independent analysis by Ekotrope of approximately 2,000 rated homes with verified ACH50 results.