HVAC doesn't have a Rollins — one dominant public consolidator disclosing decades of clean, apples-to-apples transactions. What it has instead is Limbach Holdings (Nasdaq: LMB), a smaller public building-systems firm that has been acquiring mechanical contractors at a steady clip since 2024 and, unusually for this size range, discloses purchase price alongside expected revenue and EBITDA for nearly every deal in its own SEC filings and press releases.
Worth being precise about scope up front: Limbach describes itself and its targets as "mechanical contractors" whose work spans HVAC, plumbing, and process piping — not pure-play residential HVAC. That's the same language Comfort Systems USA, the much larger public HVAC/mechanical consolidator, uses for itself. Real HVAC work is the core of what these businesses do, but if you're evaluating a residential-only HVAC shop, treat these as the closest public comp available, not an exact match.
Three real transactions, one acquirer, thirteen months
Kent Island Mechanical (September 2024): $15.0 million initial purchase price. Limbach's own guidance expected the target to contribute approximately $30 million in annual revenue and over $4 million in EBITDA beginning in 2025 — a computed multiple of roughly 0.5x revenue and, using the stated EBITDA floor, no higher than roughly 3.75x EBITDA.
Consolidated Mechanical (December 2024): $23.0 million initial purchase price against expected annualized revenue of approximately $23 million and EBITDA of $4 million beginning in 2025 — exactly 1.0x revenue and roughly 5.75x EBITDA.
Pioneer Power (July 2025): $66.1 million purchase price (which includes roughly $4.6 million of owned real property) against expected annualized revenue of approximately $120 million and adjusted EBITDA of $10 million beginning in 2026 — roughly 0.55x revenue and 6.6x EBITDA.
One honest caveat on all three: these are management's own forward-looking revenue and EBITDA expectations disclosed at the time of each deal, not trailing actuals the way some of Rollins' pest-control disclosures were. We're reporting the multiple Limbach itself was implicitly underwriting to, which is still real information — just a different kind of real than a closed year's tax return.
The pattern: multiple rises with deal size
Three data points from the same acquirer inside thirteen months, and the EBITDA multiple moves from roughly 3.75x on the smallest deal to 6.6x on the largest. That's not noise — it tracks a principle that holds across business sizes generally: larger, more diversified operations with deeper management benches command a premium over smaller, more concentrated ones, even within the same buyer's own playbook. Kent Island Mechanical, at $15 million, was priced closer to a bolt-on; Pioneer Power, a 78-year-old firm with a diversified industrial customer base, was priced like a platform.
Where the smaller end of the market actually trades
Limbach's deals — $15 million to $66 million in purchase price — are still well above what most first-time buyers are evaluating. At the true Main Street end, BizBuySell's five-year data (2021–2025) on HVAC businesses sold shows a median sale price of $750,000, on median revenue of roughly $1.48 million, at an average of 0.59x revenue and 2.75x SDE. Sold-business earnings multiples ranged from a lower quartile of 1.99x up to an upper quartile of 3.33x — meaning half of all HVAC businesses BizBuySell tracked sold somewhere inside that band.
The same data shows HVAC carrying a modest valuation premium over adjacent trades: plumbing businesses in the same dataset averaged 2.47x earnings against similar revenue, and general building-and-construction businesses averaged 2.60x — HVAC's 2.75x sits a bit above both, which BizBuySell attributes largely to HVAC's mix of recurring maintenance revenue against otherwise project-based work.
What actually moves the multiple, at any size
The through-line from both ends of this data — a $66 million platform deal and a $750,000 Main Street sale — is the same one that shows up in every recurring-revenue business we've written about: the split between one-off project work and revenue that renews on its own. A shop that's mostly new-installation and emergency repair looks like a construction business and gets priced like one. A shop with a real base of maintenance contracts and repeat service customers looks more like the recurring-revenue businesses that consistently price above the Main Street average — closer to what we've seen in alarm company valuations than to a pure project-based trade.
Before you anchor to any single "HVAC sells for X" figure, find out how much of the specific business's revenue actually renews without new sales effort each year. That number moves the defensible multiple more than the industry label on the CIM ever will.