An estimate is not a bid
An estimate is what the work will cost you to build. A bid is what you will charge to build it. The estimate is arithmetic on quantities and prices. The bid is a commercial decision laid on top of that arithmetic: overhead recovery, margin, risk, and how badly you want the job.
Keeping them apart is the single habit that makes an estimate useful. If margin is buried inside a line item, you can never answer the two questions that matter after the job closes: did we build it for what we said, and did we charge enough. An estimate that is honest about cost lets you lose a bid on price and still know your numbers were right.
Start with a takeoff, not a number
A takeoff is the measured quantity of work, pulled from the drawings and the specifications before anything is priced. Counts of fixtures and doors. Lengths of pipe, conduit, wall and curb. Areas of slab, roof, drywall and paint. Volumes of concrete, fill and excavation. Each one carries its unit, and the unit decides everything downstream: a wall priced per linear foot and a wall priced per square foot will not reconcile.
Work in one direction and record as you go: sheet number, the assembly, the measurement, the unit, and the drawing note or spec section it came from. Two things come out of that discipline. When an addendum changes a detail, you can find every line that moves. When the job is built, you can compare what you measured against what you installed, and the difference is next year's estimating accuracy.
Quantities that cannot be measured yet are not quantities. If a spec calls for an allowance, or the drawings note that a scope is by others, write it down as an open item with a name rather than a guess dressed as a number. Those open items are what the contingency line is for, and they belong in the estimate as text before they belong in it as dollars.
Here is a labeled example of one takeoff row becoming a priced line. Every figure is an input you replace with your own.
| Step | Example figure |
|---|---|
| Wall length measured from the plan | 240 linear feet |
| Wall height noted on the section | 9 feet |
| Wall area (240 × 9) | 2,160 square feet |
| Crew hours per square foot, from your own job history | 0.05 |
| Crew hours (2,160 × 0.05) | 108 hours |
| Burdened crew cost per hour, from your own payroll | $58.00 |
| Labor cost for the line (108 × $58.00) | $6,264 |
Nothing in that table is published or borrowed: the production rate comes from your own completed jobs, the hourly cost from your own payroll. Swap either and the line changes.
Organize it the way the documents are organized
An estimate that uses its own private structure has to be translated every time it meets another document: the specifications, the subcontractor's scope letter, the schedule of values, the pay application. MasterFormat exists to remove that translation step. CSI describes it as "the construction industry's standardized language for project documentation" [1], working by "organizing specifications into work results" [1] and by "aligning drawings, specs, and data so that everyone references the same structure" [1].
MasterFormat is one of the standards CSI publishes [1] [4]. Alongside it, CSI describes UniFormat as a "common classification for the description, analysis, and management of a building throughout its life cycle" and notes that "Estimators and design teams benefit from the UniFormat® cost analysis and early project design" [1]. The practical division between the two is the stage you are at: an early estimate built around building elements, a bid-stage estimate built around the work results a subcontractor actually prices.
Use one structure and hold it from takeoff to closeout. The specification section that describes the work, the estimate line that prices it, the subcontract that buys it and the schedule-of-values line that bills it should all carry the same identifier. When they do, a scope gap shows up as a missing line rather than as a surprise in month four. In our construction estimate template, each line has a division column for that identifier.
The five cost buckets
Once the quantities are measured and structured, every dollar in the estimate lands in one of five buckets.
Labor. Hours from the takeoff, priced at a burdened rate, not the bare wage. The burdened rate adds the employer's payroll taxes, insurance and the other employment costs that ride on every hour worked. An estimate built on bare wages understates its largest variable cost on every line, and the error scales with the size of the job. Our labor burden calculator builds the rate from your own payroll inputs, and our labor burden guide explains which costs belong in it.
Materials. Quantity plus the waste and breakage your own history says the assembly produces, priced from a live quote with a stated validity period. Record the quote date and the expiry against the line. Note delivery, freight and any minimum order separately rather than folding them into a unit price you will not recognize later.
Equipment. Owned or rented, with the operating cost and the idle time that comes with it. Rented equipment is priced from the rental quote; owned equipment is priced at an internal rate you set from its purchase, maintenance and fuel, so that the job pays for the machine it uses.
Subcontractors. Priced from written scopes, not from a number on a phone call. The estimate should record what each sub's price includes and, more usefully, what it excludes, because the exclusions are where the scope gaps live. A sub's number is only comparable to another sub's number when both are read against the same specification section.
General conditions and site overhead. The cost of running the site rather than building any one assembly: supervision, temporary power and water, fencing, dumpsters, sanitation, small tools, site office, safety, cleanup. These scale with the duration of the job, not with its quantities, which is why a schedule slip raises them without changing a single takeoff figure.
General conditions are not company overhead
General conditions are a job cost: they belong in the estimate and disappear when the job ends. Company overhead (your office, your estimator, your insurance, your truck payments) is recovered in the price, in the next section. Counting one as the other is how a job that looks profitable pays for nothing at the office.
Fixed vs variable, one-time vs ongoing
Federal small-business guidance draws two lines that map cleanly onto a job. The SBA defines fixed costs as "costs incurred during a specific period of time that do not change with the increase or decrease in production or services" [2], with examples including rental lease payments, salaries, property taxes, insurance, interest and depreciation [2]. It also names a third category: semi-variable costs, "composed of a mixture of both fixed and variable components", where "Costs are fixed for a set level of production or consumption and become variable after this production level is exceeded" [2]. Its examples there are telephone services, repairs, indirect materials, indirect labor, fuel and power [2].
The same guidance separates "the initial costs needed to start the business" from the expenses that recur every month: salaries, rent and utility bills [2].
On a job, that framing sorts your lines for you. Material and installed labor are variable: measure more wall, pay for more wall. The site office, the fence and the supervisor are fixed against quantity and variable against time. Fuel, small tools and cleanup behave like the SBA's semi-variable category: flat until the job runs past the level the allowance assumed, then climbing.
That sorting decides where risk sits. A quantity error moves your variable lines in proportion. A schedule error moves the time-driven lines while every quantity stays exactly as measured. They are different failures and they need different cover.
Contingency, escalation and what the index tells you
Contingency and escalation are two different provisions, and folding them into one percentage hides both.
Contingency covers scope you cannot yet measure: the open items from your takeoff, details drawn once and repeated by reference, an existing condition nobody has opened up. It is sized from the list of open items in front of you, item by item, and it shrinks as the drawings develop and each item resolves. A contingency that never moves is not a contingency; it is a hidden margin, and it will be spent as one.
Escalation covers price movement between the day you price the estimate and the day you buy the work. It is a function of time and of which commodities the job leans on. A quote that expires next month, on a job that buys the material next year, is an escalation exposure regardless of how good that quote is today.
For direction on producer prices over time, the published measure is the Bureau of Labor Statistics' Producer Price Index. The BLS describes the program in one sentence: "The Producer Price Index (PPI) program measures the average change over time in the selling prices received by domestic producers for their output." [3] It also notes that "The prices included in the PPI are from the first commercial transaction for many products and some services." [3]
Read the index for direction, not for your estimate. An index is an average across producers and products; your job buys specific items from specific suppliers on specific dates. Price from live quotes with stated expiry dates, and use the index to ask a supplier the right question about where a price is heading, not to set the number yourself.
From estimate to bid
The estimate is finished when every quantity is priced and the open items are named. The bid starts there and adds two things the estimate deliberately left out: recovery of your company overhead, and margin.
job cost = direct costs + general conditions cost base = job cost + overhead recovery bid price = cost base ÷ (1 − target margin)
Divide, do not multiply. That is the one arithmetic trap in the whole process. Markup is measured against cost and margin against price. Above zero, they are never the same number. Type a margin percentage into a markup field and the bid comes in under the profit you asked for, every time.
Here is the roll-up on a labeled example, with the two ways of applying the same percentage side by side.
| Step | Example figure |
|---|---|
| Direct costs from the estimate | $84,000 |
| General conditions | $6,000 |
| Job cost | $90,000 |
| Overhead recovery at this example's 12% | $10,800 |
| Cost base | $100,800 |
| Priced for a 15% margin ($100,800 ÷ 0.85) | $118,588 |
| Marked up 15% instead ($100,800 × 1.15) | $115,920 |
| Difference | $2,668 |
Both rows used "15%". The margin row keeps $17,788 on a $118,588 price, which is the 15% that was asked for. The markup row keeps $15,120 on a $115,920 price, which is 13.0% of what you collect. The percentages in that table (12% and 15%) are the example's own inputs, set from your own overhead and your own profit target, and nothing here suggests either figure.
Our bid price calculator runs this roll-up with your own direct costs, overhead percentage and target margin and shows each step. Our markup vs margin calculator converts between the two percentages so the number you type is the number you keep. The solicitation, the bid form, the addenda and the deadline are the subject of our guide on writing a construction bid.
Frequently asked questions
What is construction estimate?
A construction estimate is the priced cost of building a defined scope of work: quantities measured from the drawings and specifications, then priced into labor, materials, equipment, subcontractors and general conditions. It is a cost document, not a price. The price is set afterward by adding overhead recovery and margin.
How to estimate construction costs
Take off the quantities from the drawings and specs before pricing anything, structure them the way the specifications are structured, then price each line into the five cost buckets with burdened labor rates and live material quotes. Name the scope you cannot yet measure as open items, and cover them with a contingency you size from that list.
How to do a construction estimate
Read the whole set including the addenda, take off quantities with their units and their source sheet, price labor at a burdened rate and materials from dated quotes, add equipment, subcontractor scopes and general conditions, then add contingency for open scope and escalation for the gap between pricing and buyout. Keep overhead and margin out of it until you turn the estimate into a bid.
What is estimate in construction?
It is the contractor's calculation of what the work will cost to build, line by line, before any profit is added. The estimate answers what it costs you; the bid answers what you charge. Keeping the two separate is what lets you check, after the job, whether the cost was right and whether the price was enough.
Related
- Bid price calculator: direct costs, overhead and a target margin to a bid price, with every step shown.
- Markup vs margin calculator: enter either percentage and see the other, and the price each one produces.
- Labor burden calculator: build a burdened hourly rate from your own payroll inputs.
- Construction estimate template: line items by division, rolled into a direct cost and a bid price in Excel.