MASONRY MATERIAL WASTEVARIANCE TRACKINGMASONRY JOB COSTINGMARGIN LOSSCFOS $1M–$12MMASONRY MATERIAL WASTEVARIANCE TRACKINGMASONRY JOB COSTINGMARGIN LOSSCFOS $1M–$12M
MASONRY CLUSTER · PAIN POINT
MASONRY CONTRACTOR MATERIAL WASTE AND VARIANCE TRACKING.
QUICK ANSWER
Material waste in masonry work is budget-sensitive in a way most trades are not because unit masonry has a predictable waste factor that is easy to estimate and easy to verify. When actual waste runs above the estimate — more block breakage, more mortar consumption, more cut waste on complex coursing — the overage comes directly out of material margin. Most masonry contractors never track actual waste against estimated waste, so the variance is invisible until the job closes short.
Masonry estimators typically build waste factors into unit quantities — 5–10% for block, 10–15% for brick, 15–20% for cut-heavy work. When field waste runs above those factors, the material cost per unit increases. On a $300K masonry contract with 60,000 block units, a 3% waste overrun is 1,800 additional block units — at $2.50 each that is $4,500 in unbudgeted material cost that comes straight out of margin.
BY JOSH LUEBKERPublished: May 2026Updated: May 2026
THE WASTE FACTORS
WHAT NORMAL MASONRY WASTE LOOKS LIKE — AND WHEN IT IS RUNNING OVER.
CONCRETE MASONRY UNIT (CMU)
Standard Waste: 5–10%
CMU waste runs 5–7% on straight runs with minimal cutting. Waste climbs to 8–10% on projects with multiple openings, bond beams, and coursing changes. Above 12% waste on CMU is a signal — either the field is handling block carelessly, the estimator underestimated cutting complexity, or the plans changed after bid. Identify the cause before the next delivery is placed.
BRICK
Standard Waste: 10–15%
Brick waste runs 10–12% on standard running bond with limited cuts. Herringbone patterns, soldier courses, and radius work push waste to 15–22%. If the estimate was built on standard bond assumptions and the field has significant decorative coursing, the waste factor in the estimate is understated. This is an estimate error — and potentially a change order if the decorative work was added after bid.
MORTAR
Standard Waste: 15–25%
Mortar waste is the most variable masonry material. Weather, joint size variation, and mixing efficiency all affect consumption. A masonry crew running wide joints or working in hot dry conditions can burn through mortar 30–40% above estimate. Track mortar bag consumption weekly against the estimate. Mortar overruns are often a quality control signal — crews padding joints to make up for coursing errors.
HOW TO TRACK IT
A WEEKLY MATERIAL VARIANCE SYSTEM THAT TAKES 20 MINUTES.
Count units placed per week by material type — block, brick, mortar bags — from the foreman’s daily count or delivery receipts
Compare units delivered to units placed — the difference is waste. Calculate waste percentage: (delivered − placed) ÷ delivered
Compare actual waste percentage to estimate waste factor — if actual is running 3–5 points above estimate, identify the cause this week
Track cumulative waste variance by material type from project start — so the total overrun is visible at any point, not just at material closeout
Adjust future delivery orders based on actual consumption rate — if waste is running high, reduce the next delivery order to avoid over-purchasing and tying up cash in excess material on site
The cash implication: Over-ordering material because waste is running hot ties up cash in material sitting on site. A masonry contractor who orders two weeks ahead based on estimate quantities when actual waste is 40% above estimate has purchased material they will not need — and cannot return — and has reduced their available cash unnecessarily. Track waste before ordering.
COMMON QUESTIONS
FREQUENTLY ASKED.
Four main causes: plan complexity greater than the estimate assumed (more cuts, more coursing changes, more special shapes), field handling practices (block being dropped or broken during placement), weather conditions affecting mortar workability, and crew skill level on decorative or complex coursing. Identify the cause early because each one has a different fix. Complexity is a change order opportunity. Handling practices are a field supervision conversation. Weather is a scheduling adjustment. Skill is a crew assignment decision.
Only if the current estimate waste factor is genuinely below what your field consistently produces. If your historical waste on CMU is 8% and you have been estimating at 6%, increase the estimate factor. But check the cause first — if high waste on the current project is driven by plan complexity that is atypical, adjusting the standard estimate factor will overprice normal work. Track waste by project type so the estimate factor reflects the right type of work.
Yes. Material variance tracking is part of the monthly cost-to-complete for masonry contractors — actual material cost per unit placed vs estimated cost per unit, by material type. When a material type is running over, the first question is whether it is price variance (paid more than estimated per unit), quantity variance (used more units than estimated), or waste variance (delivered more than placed). Each has a different management response.
Josh Luebker
Fractional CFO · The Construction CFO
Former commercial construction project manager and master electrician. Managed 150+ projects totaling $300M+. Now fractional CFO for commercial subcontractors doing $1M–$12M. About Josh → | LinkedIn →
