Concrete Contractor Documentation Requirements

ACI 318 Documentation Requirements

ACI 318, the Building Code Requirements for Structural Concrete, establishes the baseline documentation that all concrete work on building projects must maintain. The code requires documentation at every stage — from mix design approval through final strength verification.

Key ACI 318 documentation requirements include mix design approvals (submitted before first pour), batch plant qualifications, delivery records for every truckload, field sampling and testing records, and compressive strength test results. When special inspection is required under IBC, these records are submitted to the building official and become part of the permanent project file.

What Must Appear on Every Batch Ticket

Every concrete truck that arrives on your jobsite must bring a batch ticket. This document is your proof that the concrete delivered matched the approved mix design. Required information includes:

• Batch plant name, location, and contact
• Design mix designation and approval reference
• Date and time of batching
• Truck and driver identification
• Actual water/cement ratio and admixtures used
• Slump and air content at plant (if tested)
• Volume of this load and cumulative volume
• Maximum aggregate size and gradation

Never accept concrete without a batch ticket. If the ticket shows deviations from the approved mix design, document the deviation, notify the inspector, and determine if the load should be rejected before placement.

Field Testing Documentation

For each set of cylinders taken (required per ACI 318 at a minimum frequency of one set per 50 cubic yards or each day's pour), document: slump test result, air content test result, concrete temperature, ambient temperature, time of sampling, truck load and cumulative volume, and location in the structure where this load was placed. Make cylinders at the same time as the slump test.

At 7 days and 28 days, cylinder break results must be documented with: specimen ID, break date, age, load at failure, calculated compressive strength (psi), and break type. A single cylinder break below f'c (design strength) is not automatically a failure — ACI 318 allows averages of two cylinders to determine compliance.

Curing Documentation

Curing is where many contractors under-document. ACI 308 (Guide to External Curing of Concrete) requires curing records to document: curing method selected (water curing, curing compound, forms-in-place, insulating blankets), start time of curing relative to placement, duration of curing, ambient and concrete temperatures during curing, and any deviations from the curing plan.

For cold weather concrete (below 40°F), temperature monitoring records every 4-8 hours for the protection period are required. Document thermometer placement, readings, and any protective measures adjusted during the curing period. Missing cold weather records are a frequent cause of dispute when cylinders come in low.

Change Order Documentation for Concrete

Document every change before pouring. Common concrete change orders include: additional concrete ordered beyond contract volume (document with separate tickets and a T&M ticket), pump adds (document pump truck location, hose length, additional time), changes to mix design (require written engineer approval before placing), and added admixtures (document mix ID change and approval).

Verbal direction to change quantities or mixes must be followed by written confirmation before you proceed. A text message or email from the GC counts — save everything. Disputes about concrete quantities are among the most common in construction.