FIX Electrical Segment Surges 81% but Valuation Caution Persists

What happened

Comfort Systems USA's Q2 results revealed an 81.2% surge in Electrical segment revenues, driven by data-center demand and recent acquisitions, while Mechanical grew 40.2%. This performance aligns with the company's increasing exposure to technology-sector projects, which represented 45.8% of revenue in Q3 2025. However, the stock trades at a demanding valuation (P/E 57.7x, EV/EBITDA 58.6x) and recent margins included one-time benefits such as cumulative catch-up accounting and a bankruptcy recovery. The master report also flags concentration risk, with one customer accounting for 13.3% of 2024 revenue. While the growth is impressive, it does not resolve concerns about sustainability of margins and backlog conversion quality.

Implication

The strong electrical growth confirms the data-center thesis but increases concentration risk, as technology already accounts for over 40% of revenue. The WAIT rating remains appropriate because the valuation embeds peak-cycle fundamentals and the margin quality is uncertain. Investors should monitor whether gross margin can sustain above 23% without accounting-driven boosts and whether RPO conversion stays within the 65-75% guidance. A pullback toward $1,100 or evidence of clean quarters would improve the risk-reward. Until then, the stock is vulnerable to any slowdown in hyperscaler capex or margin mean-reversion.

Thesis delta

The new data on 81% electrical growth does not change the WAIT rating. It reinforces the company's strong momentum but also heightens concerns about customer concentration and reliance on the data-center cycle. The core thesis remains that the stock is priced for peak-cycle fundamentals and lacks margin of safety.