LMB — Limbach Holdings, Inc. · 2026-09-09 · Verdict: WATCH · Conviction 2

Price $49.54 (screen row price, 2026-09-09; no live price used) · Mkt cap $591M · EV $614M (pro forma ~$707M) · EV/normalised EBIT 15.2x · FCF yield 6.8% on EV · Net debt $23.5M at 6/30/26 (~$117M pro forma) · ADV ~$19.8M Sources read: 10-K 2026-03-02 (Items 1, 1A, 7), 10-Q 2026-08-04, DEF 14A 2026-04-23, 8-Ks 2026-05-05, 2026-07-24, 2026-08-04, 2026-09-01, Form 4s (12m), Q2 2026 call transcript.

Desk stats - Revenue trend: FY2025 revenue +24.7% to $646.8M, but only $18.9M of the $128.0M increase was organic; $109.1M was acquisition-related (10-K 2025, Item 7). Q2 2026 revenue +21.9% to $173.5M, of which $30.9M was Pioneer Power and $0.3M organic; H1 2026 organic revenue fell $17.5M, or 6.4%, with ODR organic -4.3% (Q2 8-K, Supplemental Revenue Disclosures). - Normalised after-tax operating profit: TTM to 6/30/26 GAAP operating income $39.3M (FY2025 $49.454M − H1 2025 $18.553M + H1 2026 $8.385M). One adjustment: add back $1.1M of acquisition-related retention expense and change in fair value of contingent consideration (10-K Item 7; 10-Q Item 2), which is deal consideration, not operations. No impairments, discontinued operations, litigation or one-off tax items in the window. Normalised EBIT $40.4M vs GAAP $39.3M; at 25% tax, $30.3M. Stock compensation (~$9.5M/yr) and $8.2M of acquired-intangible amortisation are not added back; adding amortisation back gives $36.5M. - EV / normalised after-tax profit: EV = $590.6M equity (11,921,067 shares, 10-Q cover) + $41.05M total debt (revolver $17.5M, finance leases $18.2M, financing liability $5.4M) − $17.6M cash and restricted cash = $614M, or 20.3x. Pro forma for CYMCOR ($30M, 8-K 2026-08-04) and 1901 Inc. ($63M plus up to $6M earnout, 8-K 2026-09-01), both revolver-funded: EV ~$707M, 23.3x before their earnings. - Leverage: net debt / normalised EBITDA 0.33x at 6/30/26 (TTM adjusted EBITDA $71.6M: FY2025 $81.802M per DEF 14A pay-versus-performance, − H1 2025 $32.820M + H1 2026 $22.610M). Pro forma for the $93M of August–September deals: ~1.6x, plus $10.0M of pre-existing contingent consideration (10-K, Material Cash Requirements) and the new $6M earnout. - Is the growth sustainable? Bought, not organic, and what was bought carries worse margins: on 2026-08-04 guidance was cut from $90–94M to $78–84M of adjusted EBITDA with gross margin reset from 26–27% to 23–24%, while revenue guidance went up to $760–790M. - What the screen got wrong: it scored FY2025 growth (+24.7% revenue, +28.0% EBIT) without reading that the growth was acquired; it used LongTermDebtNoncurrent and missed the $4.862M current portion of debt; and it predates $93M of revolver-funded acquisitions that take leverage from 0.3x to ~1.6x. The honest trailing multiple is 20.3x, not 16.4x.

1. What the business actually does

Limbach designs, installs, services and maintains mechanical, electrical, plumbing and controls ("MEPC") systems in existing mission-critical buildings: hospitals, industrial plants, data centres, labs, universities (10-K 2025, Item 1). Two segments: Owner Direct Relationships (ODR), contracting straight with the building owner for planning, service, retrofits and rental equipment, and General Contractor Relationships (GCR), traditional subcontracting. The five-year strategy has been to shift mix to ODR, which reached 75.1% of 2025 revenue against a 70–80% target. About 1,500 staff at year-end across 21 offices, roughly 900 of them craft and much of it union, with participation in around 70 multiemployer pension plans (Item 7). It carries $1.0bn of surety bonding capacity. No customer exceeds 10% of revenue in either segment.

2. Why it might be mispriced — the edge case

There is no clean edge case, and that caps the verdict. The stock is 56.6% below its 52-week high and down 41% in six months (universe_v2.csv) for a fully disclosed reason: a guidance cut. Not an index deletion, spin-off, forced seller or misunderstood segment. The one thing a screen genuinely mis-reads here — the composition of growth — works against the stock, not for it. The nearest argument is that a serial acquirer is being marked down for one bad half while buying earnings cheaply: 1901 at $63M for a stated $11M of 2027 adjusted EBITDA is 5.7x, CYMCOR at $30M for $4M is 7.5x. That justifies watching, not owning at 20x trailing.

3. Unit economics and growth

The margin reset is the story. Total gross margin fell from 27.8% in H1 2025 to 21.9% in H1 2026; ODR from 29.0% to 23.5%, GCR from 24.7% to 17.5% (Q2 8-K, segment tables). Management cites Pioneer Power's lower margin profile, the absence of prior-year project write-ups, and "competition for skilled labor and materials associated with construction activity in data center markets" (10-Q, Item 2). H1 operating income fell 54.8% to $8.4M. Part of the decline is normalisation, not decay: FY2024 carried $3.9M of ODR and $3.3M of GCR write-ups, versus FY2025's $2.2M of GCR write-ups against $1.1M of ODR write-downs (10-K Item 7). Returns are unremarkable: $40.4M normalised EBIT on $203.1M equity plus $41.1M debt is roughly 12–13% after tax, against $72.6M goodwill and $45.8M intangibles on a $404M balance sheet. Cash conversion is the real strength — FY2025 CFO $45.7M on $3.8M capex; Q2 2026 CFO of $18.7M was the second-highest second quarter since the IPO (Q2 call, CFO). The offset is working capital, which consumed $26.2M in 2025 and $18.5M in 2024, so the "free cash flow = 75% of adjusted EBITDA" guide, defined to exclude working-capital changes, flatters real cash.

4. Balance sheet and capital allocation

At 6/30/26: $41.1M debt, $17.5M cash, $75.6M revolver availability, all covenants met. The revolver was upsized twice in fourteen months, $50M to $100M in June 2025 and $100M to $125M on 2026-07-24, then drawn within four weeks to fund CYMCOR and 1901. That sequence is the flag: $93M of debt-funded acquisitions in the same quarter management said the environment had deteriorated. Share count rose from 11,626,814 to 11,921,067 in six months, with $12.0M of tax paid on net-share settlement and no buyback. Insiders sold 32,304 shares for $2.73M over twelve months with zero open-market purchases (Form 4 summary), including the CFO selling into $77–$100 in March and April 2026. Officers and directors hold 7.0%; Wasatch Advisors 8.4% (DEF 14A, as of 2026-04-17). Annual cash bonus is tied to adjusted EBITDA; 2025 long-term awards moved to relative TSR.

5. Management: what they said versus what they did

On 2026-05-05 management reaffirmed $90–94M of adjusted EBITDA and called Q1 "in line with our expectations" with "accelerating organic revenue growth" ahead — in a quarter when organic revenue fell 13.4% and adjusted EBITDA fell 41.7%. Thirteen weeks later the EBITDA guide came down 13%. The CEO was candid on the call: "I do think we needed to reset from a guidance perspective." Bookings of $616M over three quarters are real, and Pioneer's gross margin is up about 150bp since acquisition. But the revised guide still requires H2 adjusted EBITDA of $55.4–61.4M against $49.0M in H2 2025 (+13% to +25%), and H2 operating income near $39–41M against $30.9M — a swing from -55% in H1 to roughly +30% in H2. H1 shows no evidence for that yet.

6. Valuation

All cases are 2027, pro forma for both deals, ~12.2M diluted shares and $110–130M net debt. - Base (45%): revenue ~$950M, adjusted EBITDA $100M (10.5%), D&A $24M, stock comp $10M, EBIT $66M at 11x EV/EBIT → equity ~$616M = $50/share. - Bear (30%): price sensitivity persists, integration drags, gross margin near 22%, adjusted EBITDA $80M, EBIT $48M at 9x → equity ~$320M = $26/share. - Bull (25%): margin recovers toward 25–26% gross, CYMCOR pull-through lands, adjusted EBITDA $115M, EBIT $80M at 13x → equity ~$940M = $77/share. Probability-weighted: $49.6 against a $49.54 price. Reverse DCF: the pro forma EV of ~$707M on ~$39M of pro forma normalised after-tax profit is ~18x, against 10x for a no-growth perpetuity at a 10% cost of capital — so the price already embeds roughly 5–6% perpetual profit growth and the 23–24% gross margin holding as a floor.

7. Catalysts and timeline

Q3 2026 results in November: first read on the H2 ramp, first disclosure of 1901's contribution, and the quarter that validates or breaks the bookings-convert story. 2027 guidance in March 2027. Slower burn: Pioneer's stated two-to-three-year march to company-average gross margin, and CYMCOR pull-through bookings.

8. Pre-registered kill criteria

1. Q3 2026 consolidated gross margin below 23%, the low end of the reset guide, or any further cut to FY2026 adjusted EBITDA guidance.
2. ODR organic revenue growth negative again in Q3 2026, making it three of four quarters.
3. Pro forma net debt / trailing adjusted EBITDA above 2.5x at any quarter-end, or another acquisition above $50M on the revolver before Pioneer reaches company-average gross margin.
4. Continued insider net selling with still zero open-market purchases through the Q3 print, at a price 55%+ off the high.

9. Verdict and one-paragraph summary

WATCH, conviction 2. Limbach is a decent business — owner-direct mix at 75% of revenue, no customer over 10%, $1bn of bonding capacity, better-than-typical cash conversion — that the screen picked up on stale arithmetic. The FY2025 growth that qualified it was bought: $109.1M of the $128.0M revenue increase came from acquisitions, and organic revenue has since gone negative, down 6.4% in H1 2026, while gross margin fell nearly 600bp and management cut adjusted EBITDA guidance from $90–94M to $78–84M. On trailing normalised numbers the stock is 20.3x after-tax operating profit, not the screen's 16.4x, and pro forma for $93M of revolver-funded acquisitions closed in August and September it is ~23x on an EV near $707M, with leverage up from 0.3x to ~1.6x. Management is candid and the deals look sensibly priced at 5.7x and 7.5x forward EBITDA, but the guide still needs H2 EBITDA up 13–25% right after a half in which operating income fell 55%, and insiders have sold $2.7M with no buys. Probability-weighted fair value lands within a dollar of the price, so the November quarter, not the stock, is the thing to have an opinion about.

Research for discussion, not investment advice. Positions and sizing are the reader's decision.