Every job you underprice costs you real money. A solid construction estimating process takes three inputs: your actual labor hours, your real material costs, and a number that covers your overhead. Get those three right, and you can price any job with confidence. Miss one, and you're working for less than you think.
Most estimating advice stops at "track your costs." This article goes further. You'll get a repeatable, step-by-step method to build a job cost breakdown from scratch, with real numbers from common trade jobs, so you stop leaving money on the table every time you quote.
Key takeaways
- Every estimate has three parts: labor, materials, and overhead burden. Skip any one and your price is wrong before the job starts.
- Your loaded labor rate (what labor actually costs you per hour, including taxes, insurance, and burden) is almost always 1.25 to 1.40 times the wage you pay.
- Overhead is not optional padding. It is the real cost of running your business: truck, phone, insurance, licenses, tools. If your price doesn't recover it, you pay it out of your own pocket.
- A markup of 15 to 25 percent on top of your total job cost is a common starting point for small trade contractors, but your market and overhead structure should drive that number.
- Running the same math on every job, even small ones, builds the habit that protects you on the big ones.
What do you actually need before you start an estimate?
Before you touch a calculator, gather four things:
- A clear scope of work. What exactly are you doing? "Install a 200-amp panel" is a scope. "Some electrical work" is not. Vague scope produces vague prices and arguments later.
- A site visit or detailed plans. You cannot estimate what you cannot see. A bathroom remodel in a 1950s house with cast iron drain lines and knob-and-tube wiring is a different job than a remodel in a 2005 build.
- Current material pricing. Lumber, copper, PVC, fixtures — prices shift. Pull quotes from your supplier for anything over a few hundred dollars. Do not rely on memory or last year's numbers.
- Your own cost numbers. Your hourly wage cost, your overhead per month, and your desired markup. These come from your books, not from guessing.
Step 1: Build your labor number the right way
Labor is where most contractors lose money. The mistake is pricing your time at what you pay yourself or your guys, not what it actually costs to put them on a job.
Your loaded labor rate is the true cost per hour of one worker on a job. It includes wages plus every dollar your business spends to have that person working: payroll taxes, workers' comp, general liability (the portion tied to labor), and any benefits.
A common rule of thumb: loaded labor rate runs 1.25 to 1.40 times the base wage. If you pay a journeyman electrician $38 per hour, your loaded rate is roughly $47 to $53 per hour. Use $50 as a working number and you're in the ballpark.
How to calculate labor cost for a job:
| Step | Example: 200-Amp Panel Swap |
|---|---|
| Estimate hours on the job | 8 hours (1 electrician) |
| Loaded labor rate | $50/hr |
| Subtotal: labor cost | $400 |
For a bathroom tile job with two workers over three days:
| Step | Example: Tile Installation |
|---|---|
| Hours per worker | 24 hours each |
| Total labor hours | 48 hours |
| Loaded rate | $38/hr |
| Subtotal: labor cost | $1,824 |
Write down your labor subtotal. Do not move on until that number is solid. Every hour you underestimate here is an hour you work for free.
Step 2: Price out materials without leaving gaps
A good labor and material estimate covers everything that goes into the job: not just the main materials, but every connector, every fitting, every tube of caulk.
Build your material list line by line. Go through the scope of work and list every material you will touch. Then price each one at your actual cost from your supplier.
Add a material waste factor of 5 to 15 percent depending on the job. Tile work typically runs 10 percent waste for cuts and breakage. Rough framing lumber might run 5 to 8 percent. Electrical wire on a complex run can vary more. If you're not sure, use 10 percent and move on.
Example: HVAC condensing unit replacement
| Material | Qty | Unit Cost | Total |
|---|---|---|---|
| 3-ton condensing unit | 1 | $1,450 | $1,450 |
| Line set (25 ft.) | 1 | $180 | $180 |
| Disconnect box | 1 | $45 | $45 |
| Refrigerant (R-410A, 5 lbs.) | 5 | $22 | $110 |
| Misc. fittings, tape, wire | 1 lot | $60 | $60 |
| Materials subtotal | $1,845 | ||
| Waste factor (5%) | $92 | ||
| Adjusted materials total | $1,937 |
Pull your materials total and write it next to your labor number.
Step 3: Apply your overhead burden
Overhead is what it costs to keep your business running, whether you're on a job or not. Truck payment, fuel, tools, phone, software, liability insurance, license fees, continuing education. If you don't recover overhead in your prices, you pay it out of pocket.
How to calculate your overhead rate:
- Add up all your business expenses for a month (not including materials or direct labor pay). This is your monthly overhead.
- Estimate how many billable hours you work per month. Most solo contractors bill 100 to 140 hours per month after accounting for drive time, admin, and downtime.
- Divide monthly overhead by billable hours. That's your overhead cost per hour.
Example:
| Expense | Monthly Cost |
|---|---|
| Truck payment + insurance | $900 |
| Fuel | $400 |
| General liability insurance | $250 |
| Tools, equipment maintenance | $200 |
| Phone, software, admin | $150 |
| License fees (amortized) | $50 |
| Total monthly overhead | $1,950 |
At 130 billable hours per month: $1,950 / 130 = $15 per hour overhead burden
Multiply that overhead rate by the hours on your job. For the 8-hour panel swap: $15 x 8 = $120 in overhead to recover.
For larger jobs, some contractors apply overhead as a percentage of total direct costs instead. Either method works as long as you use it consistently. Pick one and stick with it.
Step 4: Add your markup for profit
Job cost is the sum of labor, materials, and overhead. Markup is what you add on top to generate actual profit. These are not the same thing.
A common range for small trade contractors is 15 to 25 percent markup on total job cost. Where you land depends on your market, your reputation, and your capacity. If your schedule is full, price higher. If you're chasing volume to cover overhead, you have some flexibility. But never price below your job cost plus a reasonable profit. That's called losing money slowly.
Putting it together: full estimate example
Using the HVAC condensing unit job from Step 2:
| Line Item | Amount |
|---|---|
| Labor (6 hrs x $52 loaded rate) | $312 |
| Materials (adjusted total) | $1,937 |
| Overhead burden (6 hrs x $15) | $90 |
| Total job cost | $2,339 |
| Markup (20%) | $468 |
| Customer price | $2,807 |
Round to $2,800 for a clean quote. A condensing unit replacement typically runs $2,500 to $4,500 installed depending on unit size and market. That number puts you in a credible range, not a desperate one.
Tips to protect your estimate in the field
- Get a signed scope before you start. If the customer adds work mid-job, that's a change order, not a favor.
- Log your actual hours on every job. Compare them to your estimate. The gaps show you where your estimating method needs adjustment.
- Never discount labor. If a customer pushes back on price, look at material alternatives or reduce scope. Your time costs what it costs.
- Add a contingency on older buildings. Five to ten percent on top of your total for jobs in structures built before 1980. You will find surprises.
- Update your overhead number twice a year. Fuel, insurance, and equipment costs change. Your pricing needs to keep up.
Frequently asked questions
How do I estimate a job when I'm not sure how long it will take?
Break the job into phases and estimate each one separately. For work you've done before, pull your time logs and average your actual hours. For unfamiliar work, talk to a supplier or another contractor who has done it. Then add a 10 to 15 percent time buffer on top of your estimate. It's better to quote slightly high and deliver under budget than to quote tight and eat the hours.
Should I show the customer a breakdown of labor and materials, or just give them one total price?
Most experienced contractors give customers a total price, not a line-by-line breakdown. When you itemize labor and materials separately, customers start negotiating each line instead of evaluating the overall value. Exceptions include commercial work and government contracts, where detailed breakdowns are often required by the contract.
What's the difference between markup and margin, and does it matter?
It matters a lot. A 20 percent markup on a $2,339 job cost means you add $468, giving you a $2,807 price and a 16.7 percent profit margin. If you price for a 20 percent margin instead, you divide the job cost by 0.80, which gives you a $2,924 price. Confusing the two can cost you real money on every job. Know which one you're using before you set your rate.
How do I handle jobs where material prices change between the estimate and the start date?
Include a price validity clause in your estimate: "This quote is valid for 30 days." For jobs with long lead times or volatile materials like copper or lumber, note that material costs are subject to change at time of purchase and get customer acknowledgment in writing before ordering.
What if my price is higher than a competitor's?
Find out what is actually different before you lower your number. A lower bid might exclude permits, haul-away, or certain materials. Ask the customer what the competitor included. If your scope is the same and you're still higher, you can explain your value. If you can't justify the difference, look at your overhead structure, not your profit margin.
How do I estimate jobs that are mostly labor with very few materials?
The same method applies, but materials become a smaller line item. Appliance installations, HVAC maintenance calls, and rough-in inspections are often labor-heavy. In those cases, your overhead burden per hour matters even more because you have fewer material dollars to spread overhead across. Make sure your hourly rate is fully loaded before you quote.
How often should I revisit my estimating method?
At least twice a year, and after any job that came in significantly over or under budget. Track your estimate vs. actual hours on every job. If you're consistently short on hours in one trade, your production rates are off. If you're consistently over on materials, your waste factors need adjustment. The estimate is only as good as the feedback you feed back into it.
Estimating isn't a talent you either have or don't. It's a process you run every time, on every job, until the math becomes automatic. Build the habit on the small jobs and you won't be guessing on the big ones. If you're still writing estimates by hand and chasing payments by text, it's worth looking at what a tool built for contractors can do for that part of your day. Krue handles estimates, invoicing, and payment follow-up in one place, designed around how contractors actually work, not how accountants think they should.
