Construction Preconstruction Services: What GCs Do Before the First Shovel
Preconstruction is where GCs earn their money on negotiated projects — and where owners either set themselves up for a successful project or a contentious one. Done right, precon surfaces budget problems while design changes are still cheap, eliminates coordination gaps before they become field RFIs, and produces a GMP that both parties can trust. This guide covers what precon services actually include, how to structure them, and how GC precon fees work.
What Are Preconstruction Services?
Preconstruction services are the work a GC performs before a construction contract is executed — or before a GMP is established on a construction manager at-risk (CMAR) project. The GC engages during the design phase, contributing construction expertise to inform design decisions, control costs, and compress the overall project schedule.
Precon is most common on negotiated delivery methods: CM at-Risk, Design-Build, and negotiated GMP. On hard-bid design-bid-build projects, the owner performs the equivalent work through their design team and project manager — often less effectively, since the firm that will actually build the project isn't in the room.
Core Preconstruction Services
The GC produces progressively refined estimates as design advances through SD, DD, and CD phases. Each estimate reconciles against the owner's program budget and flags variances early.
The GC's field and estimating staff review drawings and specifications to identify details that will be difficult, expensive, or impossible to build as drawn. Constructability issues caught in design cost a fraction of what they cost as field RFIs or rework.
- •Coordination conflicts between structural, mechanical, and architectural elements
- •Details that require unusual sequencing or cannot be built with standard equipment
- •Specification conflicts (two sections requiring incompatible products)
- •Long-lead items identified early enough to order before they delay the schedule
- •Missing details that will require RFIs during construction (issued as design comments)
Value engineering is a systematic review of design elements to find equivalent or better function at lower cost. On projects where the owner's budget is under pressure, VE is the mechanism for closing the gap between what the design costs and what the owner can afford.
Good VE preserves design intent while reducing cost. Bad VE degrades quality under the guise of savings. GCs who present VE items should include: estimated savings, quality impact, schedule impact, and the design change required to implement it.
The GC develops a preliminary construction schedule during precon, identifying the critical path, long-lead procurement items, and phasing constraints. This schedule drives the GMP and becomes the baseline against which field progress is measured.
- •Milestone schedule aligned to owner occupancy and phased turnover requirements
- •Long-lead equipment list: steel, glazing systems, elevators, switchgear, chillers
- •Permit timeline and jurisdiction-specific review durations
- •Phasing plan for occupied facilities or multi-building campuses
- •Design deliverable schedule tied to construction start requirements
On fast-track projects, GCs issue early bid packages during precon to compress the overall schedule — most commonly for site work, foundations, and structural steel, which must start before construction documents are 100% complete.
Precon is also when GC teams prequalify subs for the project: reviewing bonding capacity, insurance, safety records, and relevant project experience. Building a qualified bidder list early prevents scrambling during the formal bid package solicitation.
How the construction site will be organized affects cost, safety, and schedule. Precon is when GCs plan crane location and picks, laydown areas, temporary utilities, site access and traffic control, adjacent-property protections, and workforce staging.
For urban infill projects especially, site logistics planning requires coordination with the owner, local authorities, and neighboring property owners — work that cannot wait until construction starts without creating costly delays and conflicts.
Precon Fee Structures
GCs are typically compensated for preconstruction services in one of three ways:
| Structure | How It Works | Typical On | Risk |
|---|---|---|---|
| Lump-sum precon fee | Fixed fee for defined precon scope; paid regardless of whether project proceeds | CMAR, smaller projects | GC absorbs scope creep if precon drags |
| Precon fee credited at GMP | GC charges precon fee; fee is credited back to owner if GMP is executed | Negotiated GMP projects | GC carries fee risk if project doesn't proceed |
| Precon included in GC fee | No separate precon fee; GC absorbs precon cost in anticipation of construction fee | Long-term owner relationships, repeat clients | GC fully at risk if project doesn't proceed to construction |
| T&M precon | GC bills actual staff hours at agreed rates | Complex, long-duration precon phases | Owner bears cost risk if precon extends |
Typical precon fees for commercial projects range from $50,000 to $500,000+ depending on project complexity, design phase at engagement, and the depth of services provided. As a rough benchmark, precon fees often run 0.5–1.5% of estimated construction cost on large projects, though this varies significantly.
Precon to GMP: How the Transition Works
The goal of the precon phase is to produce a GMP proposal the owner can execute with confidence. The GMP package typically includes:
- ▸GMP amount: Total contract price including all direct costs, general conditions, GC fee, and contingency
- ▸Basis of GMP documents: Specific drawing set and specification date that the GMP price is based on — critical for defining what constitutes a change order
- ▸Clarifications and assumptions: Written list of scope assumptions embedded in the GMP; items not shown on current drawings but assumed included
- ▸Exclusions: Items explicitly not included in the GMP (owner-furnished equipment, specialty consultants, etc.)
- ▸Contingency breakdown: GC contingency vs. owner contingency amounts and use protocols
- ▸Schedule: Preliminary construction schedule with key milestones and the required design deliverable dates to support it
Once the GMP is executed, the GC transitions from precon mode into construction. The project moves from schematic promises to contractual commitments — and the job cost tracking and payment application process begins in earnest.
5 Best Practices for GC Preconstruction
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1.
Assign your construction superintendent during precon. The super who will build the project should participate in constructability reviews. Their field knowledge surfaces issues that estimators and PMs miss — and their buy-in to the plan makes execution smoother.
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2.
Issue estimate reconciliations in writing. Every time a GC estimate exceeds the owner's budget, document the gap and the options to close it. Verbal "we're working on it" updates erode trust. Written reconciliation logs protect both parties and drive design decisions.
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3.
Separate GC contingency from owner contingency in the GMP. GC contingency covers unknown conditions within the defined scope. Owner contingency covers scope changes and owner decisions. Conflating them creates disputes over who authorized what spending.
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4.
Document all VE decisions. When an owner accepts a VE item, record the savings, the quality trade-off, and any maintenance implications. VE items accepted under budget pressure and later regretted become relationship problems if the trade-off wasn't clearly communicated at the time.
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5.
Get clarifications and assumptions reviewed by counsel before GMP execution. The written clarifications and assumptions in the GMP package define the scope boundary. Vague language in assumptions creates change order ambiguity for the entire project duration. A lawyer's hour spent here is worth it.
From Precon Budget to Job Cost Tracking
SheetIntel connects your GMP estimate to field cost tracking — so the numbers you built in precon are the same numbers your superintendents track against in the field.
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