General conditions in a construction estimate: what to include

General conditions are the job costs you can't measure on the drawings: the people running the work, temporary facilities, dumpsters, permits, insurance. No takeoff will produce them for you. That's exactly why they get forgotten, or thrown in as a guess. Here's a checklist by category, how to price each line, and a complete example.

General conditions vs. overhead

The two get mixed up all the time. They don't cover the same costs.

• General conditions: the costs of this job. They exist because this project exists, and they depend mostly on its duration: superintendent, site toilet, fencing, dumpsters, building permit.
• Overhead: the costs of the office, which exist with or without this project: rent, accounting, the estimator's salary, software, company vehicles. They're spread across projects, usually as a percentage of the cost of the work.

The simple test: if the cost goes away when the job is done, it's a general condition. If it keeps going, it's overhead. And each cost goes in one place only, never both.

The checklist, by category

Staff

• Project manager (the share of their time spent on this job)
• Superintendent or foreman
• Labourer (material handling, cleanup during the job)

Site facilities

• Site trailer (often not needed on a small house, but worth asking)
• Site toilet
• Temporary power
• Temporary heat
• Site fencing
• Protection and signage (floor protection, neighbours, the street)

Waste and cleaning

• Dumpsters (number of pickups)
• Final cleaning

Permits and fees

• Building permit
• Street occupancy permit
• Permit for a trailer or concrete pump on the street, if the municipality requires one

Insurance and bonds

• Builder's risk / job insurance
• Bonds, if the owner or the contract requires them

How to quantify each line

Each category has its own unit. That's what makes general conditions checkable.

• Staff: in hours. Not as a "percentage of time", which is hard to check. Estimate hours per week for each person, multiply by the number of weeks on site, then by your hourly rate.
• Rentals: by the week or month, from the schedule duration. Toilet, fencing, temporary power: the quantity is the length of the job. Watch out, a month that has started is usually billed in full: 16 weeks (112 days) means 4 months of rental, not 3.7.
• Temporary heat: winter months only. It doesn't follow the whole job, only the part that falls in cold weather, when you need heat for concrete, drywall or finishes.
• Dumpsters: by number of pickups. Estimate how many bins the project will fill (demolition, framing, finishes), times the price of one pickup.
• Permits, final cleaning, insurance: as a lump sum. Use the actual amount from the municipality or the insurer for this project, not an average.

Worked example: a 16-week house

Assumptions: 16-week job (112 days, so 4 months of rental), 2 winter months to heat, 6 dumpster pickups.

If the job runs 4 weeks longer

The same project now takes 20 weeks (140 days, so 5 months of rental):

• Staff: 80 h × $75 + 200 h × $65 + 160 h × $40 = 6,000 + 13,000 + 6,400 = $25,400 (+ $5,080).
• Rentals that follow the duration: 5 months × ($200 + $150 + $250) = $3,000 instead of $2,400 (+ $600).

That's $5,680 more, without a single extra stick of material. This is why general conditions need to be tied to the actual length of the job, not typed in once and forgotten.

Common mistakes

• Forgetting winter heat. A job estimated in summer can easily end up pouring the slab or taping drywall in January. Check which months the schedule falls on before pricing.
• Not following duration changes. The schedule slips three weeks, but the foreman's hours and the rental months are still from the first version. The difference above shows what that costs.
• Double-counting with overhead. The project manager is in general conditions and also in the overhead percentage. Same with an annual company liability policy: if it's already in your overhead, don't add it to the job again.
• Double-counting with subcontractors. Some trades include their own dumpster or cleanup. Read their quotes before adding yours.
• Using a percentage instead of a list. "8% for general conditions" can't be checked and doesn't move when the duration changes. A list of lines with quantities can, and does.
• Forgetting secondary permits. Street occupancy for a dumpster, a trailer or a concrete pump: check with the municipality where the job is.

In KOR

In KOR, the "General conditions" section always sits at the top of the estimate, even when it's empty, so it doesn't get forgotten. You can start from a usual list (staff in hours, site facilities, waste and cleaning, permits and fees, insurance and bonds) that comes without prices: you enter your own rates once, in the Library, then add it to each project. Rental lines can follow the project schedule's duration, in weeks or months: if the schedule gets longer, the quantity follows.

Summary

1. General conditions = costs of this job; overhead = costs of the office. Each cost in one place only.
2. Staff in hours, rentals by the week or month from the schedule duration, permits and insurance as lump sums.
3. A rental month that has started is often billed in full.
4. Heat only for the job's winter months.
5. When the duration changes, update the hours and the rentals.