Change Order, Added Hose Bibbs, and a Three-Week Truss Delay
You are the master plumber for a $1.2 million, 24-unit, four-story wood-frame apartment project. Your plumbing subcontract is $286,000 with a 5% contingency and a 10-week schedule. The contract requires written change orders for any extra over $1,000 and has liquidated damages of $1,000 per day. During rough-in, you discover that the 6-inch PVC storm drain from the roof cannot pass through the first-floor shear wall as drawn; rerouting will require 24 feet of additional 6-inch pipe, four fittings, two core-drilled holes, and a structural engineer's detail. The same week, the owner asks for three additional freeze-proof hose bibbs, one at each exterior stair landing, and the truss supplier announces a three-week delay. Your crew is paid $85/hour, and material markup is 15%; overhead and profit are 10% each.
1. How should you handle the storm-drain conflict, and what should happen before any work proceeds?
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I would stop that portion of the work and issue a written request for information and a change-order proposal before cutting the shear wall or installing the reroute. The conflict is a design change, not a field adjustment, because it affects a structural shear wall and requires an engineer's detail. I would document the existing condition with photos and a sketch, obtain the structural engineer's approved penetration and reinforcement detail, and price the added 24 feet of 6-inch PVC, four fittings, two core-drilled holes, firestopping, labor, and any inspection fees. I would include schedule impact and state that the work is not authorized until the owner signs the change order. Proceeding without written authorization risks nonpayment and liability for cutting a structural element without approval.
2. Estimate a selling price for the three added hose bibbs using the stated labor and markup assumptions.
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Using a planning estimate of 4 labor-hours per freeze-proof hose bibb, including core drilling, trim, and testing, the labor is 3 × 4 × $85 = $1,020. Material at $120 per bibb is $360. Apply the 15% material markup: $360 × 1.15 = $414. The direct subtotal is $1,020 + $414 = $1,434. Apply 10% overhead: $143.40, giving $1,577.40. Apply 10% profit: $157.74, giving a selling price of about $1,735. I would round to $1,750 and state the assumptions in the change order. The schedule impact is about one crew day. The change is over the $1,000 threshold, so a written change order is required before installation.
3. What is your position on the three-week truss delay and the liquidated-damages exposure?
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The truss delay is not caused by the plumbing subcontractor, so I would notify the general contractor and owner in writing immediately, within the contract's notice period, and request a time extension of three weeks. I would keep daily records of the delay, the truss supplier's notice, and any resequencing I perform, such as moving rough-in to another floor or prefabricating assemblies. I would not accept liquidated damages for that period if the delay is excusable and properly documented. At the same time, I would separate my own delays from the truss delay and avoid claiming extension for work I could have accelerated. The change-order work for the storm drain and hose bibbs should be priced with its own schedule impact, because added work may justify additional time beyond the truss extension.