Plumbing Contractor Rough In Cash Hole

TL;DR: Plumbing subcontract schedules of values routinely underbill the rough-in phases — underground and above-slab — which are the most labor and material intensive parts of the job. A GC-drafted SOV might assign 20% of contract value to rough-in that represents 40% of actual cost. The result is a cash hole in the first 40% of the project funded from operating cash or the line of credit. SPM reviews every plumbing SOV before signing and recommends rough-in phase reweighting to match actual cost distribution.

The Problem

What You Are Dealing With

Underground Rough-In Has the Least SOV Weight and the Highest Cost

Underground plumbing — trenching, underground drain lines, cleanouts, building main — is the most labor-intensive and material-intensive phase of a commercial plumbing subcontract. It requires the most equipment, the most labor, and occurs before any vertical work begins. A GC-drafted SOV typically assigns 8–12% of contract value to underground rough-in. Actual cost is often 20–28% of total contract cost. Every month of underground work is funded from operating cash at a 2:1 cost-to-billing ratio.

Above-Slab Rough-In Is Similarly Underbilled

Above-slab rough-in — drain lines, vent stacks, supply rough-in — represents another 15–20% of total plumbing cost but is often consolidated with trim-out in the SOV into a single 'Rough-In and Trim' milestone. This blending allows the GC to defer approval of rough-in billing until trim-out is complete — months after the rough-in labor and material were incurred.

Trim-Out and Final Are Back-Loaded With Value They Do Not Earn

Trim-out and final inspection — fixture setting, trim, testing — are the least labor-intensive phases of a plumbing subcontract but often carry 40–50% of contract value in a GC-drafted SOV. The labor is minimal. The billing is maximum. The contractor has funded the entire project from operating cash and finally gets paid well in the last 20% of the timeline.

The Fix

How to Fix It

Separate Underground, Above-Slab, Trim, and Final in the SOV

Submit your own SOV with four distinct phases weighted at actual cost distribution: underground rough-in (20–28% of contract value), above-slab rough-in (15–20%), trim-out (20–25%), and final including testing and inspection (10–15%). Mobilization as a separate first line at 5–8%. This structure recovers costs as they are incurred rather than at completion.

Mobilization and Material Procurement as Separate Lines

Pipe, fittings, and specialty material ordered before installation begins need a procurement line in the SOV — billable at delivery. On a $400,000 plumbing subcontract with $80,000 in pre-ordered material, a delivery line recovers that cash 4–8 weeks earlier than waiting for installation milestones.

Negotiate Rough-In Inspection as a Billing Trigger

Rather than waiting for the GC's rough-in approval, negotiate language that ties billing to AHJ rough-in inspection approval — not GC approval. AHJ inspections are on a defined schedule and produce a documented pass/fail. Once the rough-in inspection passes, the billing milestone is met regardless of the GC's internal approval process.

Track Rough-In Progress Weekly Against SOV Milestones

ControlQore cost codes by plumbing phase track actual cost incurred against the SOV milestone value. When rough-in is 60% complete by cost but only 20% billed (because the SOV milestone requires 100% completion), the underbilled position is flagged on the WIP schedule. SPM uses this flag to accelerate billing on completed portions and document phase completion for early billing.

Client Outcome

Real Results — Real Numbers

Electrical Contractor (Cross-Trade Rough-In Cash Hole) · $2.3M Revenue

The plumbing rough-in dynamic is identical to electrical rough-in. SPM's SOV restructuring approach produces the same result across all MEP trades.

$365,000 in AR recovered

Including underbillings from rough-in phases completed but not yet billed under GC-drafted SOV milestones.

SOV restructured

On all new MEP subcontracts — rough-in phases weighted at actual cost distribution.

FAQ

Frequently Asked Questions

Why do plumbing contractors have cash flow problems during rough-in?

GC-drafted SOVs assign 15–20% of contract value to rough-in phases that represent 35–50% of actual cost. The cash hole between actual cost incurred and billing milestone value persists for the first 40% of the project. The fix is submitting your own SOV before signing with rough-in phases weighted at actual cost distribution.

How do I negotiate a better SOV for plumbing subcontracts?

Submit your own SOV draft before the GC's version. Include: mobilization at 5–8% of contract value, material procurement line for pre-ordered material, underground rough-in at 20–28%, above-slab rough-in at 15–20%, trim-out at 20–25%, and final at 10–15%. Frame each line as an accurate reflection of when costs are incurred, not as a special request.

What overhead rate should a plumbing contractor use in bids?

Plumbing contractors at $1M–$3M typically run 13–18% overhead. At $3M–$6M, 11–16%. Service vehicle fleet and specialty tool ownership are commonly excluded from overhead calculations even though they are fixed costs. Including them raises the rate 2–4 points and produces more accurate bids on competitive work.

How does the plumbing rough-in cash hole affect the line of credit?

When rough-in labor and material go out in months one through three and billing does not match that outflow, the difference is funded from the line of credit. On a $400,000 plumbing subcontract with a $80,000 rough-in billing gap, the LOC draw in months one through three is $80,000 — typically not paid down until trim-out billing arrives months later. Multiple simultaneous plumbing jobs stack multiple LOC draws that may never fully pay down between billing cycles.

Rough-In Is Your MostExpensive Phase. Bill It That Way.