Most contractors learn to price jobs one of two ways. Some price the whole job as a lump, based on gut feel and what the last similar job went for. Others build every bid from scratch and lose an evening to each one. Pricing by the unit sits between the two. You work out what one unit of work costs you, then let the quantities do the rest.
It works the same whether you're bidding a window replacement, a siding job, or a commercial scope. The method doesn't change with the size of the job. Only the list of items and the quantities do.
The three questions behind every price
Every item on a bid comes down to three questions:
- How much material does one unit take, including waste, fasteners, and the small parts that never make the takeoff?
- How long does it take your crew to install one unit, in labor hours, on the kind of job you're bidding?
- What does that crew time cost you, with wages, burden, and the overhead that keeps the business running?
Answer those three for one unit of work and you have a unit rate. One window. One square foot of siding. One foot of gutter. The rate is the full cost to put one of those in place, not just the material on the invoice.
The middle question is the one most people skip. Material prices are easy to look up. Crew time is not, and it's where a bid usually goes wrong. If you haven't checked how many hours your crew really spends per unit, start with labor productivity rates for estimating.
Measure the quantity, then multiply
Once you have rates for the items you install, pricing the job is mostly arithmetic. Walk the job or work from the plans, take off each item in its own unit, and multiply each quantity by its rate.
- Windows are counted each, so count the openings by size and type.
- Siding is measured by the square foot of wall area, less the openings you're not covering.
- Gutter is measured by the linear foot along the eaves, with downspouts and corners counted separately.
Add the lines up and you have the price of the work. Decide once whether overhead and fee live inside each rate or get added to the total, and stick with it, so they never get counted twice or left out. Overhead, fee, and contingency are worth getting straight before you lock that in.
Keep the units honest. If one rate is per square foot and the takeoff is in squares, or one rate is per opening and the takeoff counts sashes, the multiplication is right and the price is still wrong.
Adjust each rate to match your crew
A rate only works if it reflects how your crew actually works. A two-person crew on a remodel with tight access won't hit the same production as a full crew on new construction. Neither number is wrong. They're different rates for different conditions.
When a job doesn't fit the rate you have, adjust the rate on that bid and note why, or save a second named rate for that condition. After the job closes, compare the hours you bid per unit with the hours the crew spent, and update the rate. That loop is what turns a list of numbers into rates you trust.
If you're starting from nothing, the published unit rates give you an editable starting baseline, with the labor and material build-up shown for each item. Use them as a starting point you edit, not as a substitute for your own job data. Start with a vinyl single-hung window, HardiePlank lap siding, or a seamless K-style gutter. Treat each one as a draft until your own job data backs it up.
Why pricing by the unit is faster
The first few rates take real work. After that, each bid gets quicker, because you're not rebuilding the cost of a window every time you price a window. You pick the items, enter the quantities, and check the conditions. The time you save goes into the parts that actually change from job to job: access, scope gaps, and what the customer is really asking for.
It also makes your bids easier to explain. When a customer asks why the price is what it is, you can show them the quantity and the rate for each item instead of defending one big number.
For a larger or commercial job, the same rates feed a fuller process with scope, overhead, fee, and proposal terms. That's covered in how to price a construction project.
Your next step
Pick three items you install on almost every job. For each one, answer the three questions for a single unit, then check the hours against your last finished job. Price your next bid from those rates. If you'd rather not keep them in a spreadsheet, you can build them in a free Unit Rate AI account.