What a comment letter costs your firm: a worksheet for principals

A step-by-step worksheet that prices comment-letter and proposal time at your billing rates and gives a simple rule for whether to act.

Before you buy any AI tool or service, find out what the paperwork actually costs you. Nobody has published how long a small firm spends on a plan-review comment letter or a proposal; we looked and found nothing. So the honest starting point is your own numbers. This worksheet walks you through getting them.

Step 1: Your rates

Use your own billing rates if you have them. If not, the PKF O'Connor Davies A&E study (Oct 2025, 2024 data) reports these average billing rates:

Role	Average billing rate
Principal	$290/hr
Project manager	$230/hr
Senior engineer	$210/hr
Engineer	$170/hr
Technical staff and drafters	$140/hr

The same study reports average utilization of 62% of hours (42.7% for principals), profit of 14.7% of net fee income, and net fee income of $202,655 per employee. PKF does not publish its sample size or firm-size mix, so treat these as rough anchors, not as your firm's numbers.

Step 2: Time one letter honestly

The next time a review letter arrives, track hours by role for each stage:

Logging: getting every comment into a list or the owner's form.
Matching: reconciling it with the previous round.
Drafting responses.
Engineer review and decisions.
Assembly: putting together and sending the letter and resubmittal.

Stages 1, 2, 3 and 5 are where AI drafting can help. Stage 4 stays with the engineer in responsible charge, as every board statement we have read makes clear (see what the boards say).

Three common timing mistakes:

Counting only the person who typed the letter. Include the principal who read it and the drafter who fixed sheet references.
Timing an easy letter. Pick a typical one, or time two and average them.
Forgetting the round-two reconciliation. Matching new comments to old ones is often the slowest part, and it is easy to leave out.

Step 3: The math

Cost per round = the sum of (hours by role × rate) for stages 1, 2, 3 and 5.
Annual cost = cost per round × review rounds per project × projects per year.

A worked example with made-up hours

These hours are invented to show the arithmetic. Replace them with yours.

Say logging, matching, drafting and assembly take 3 project-manager hours and 3 engineer hours for one letter. At the PKF average rates:

3 × $230 = $690
3 × $170 = $510
Cost per round: $1,200

If a project averages 2 review rounds and you run 10 such projects a year, that is $1,200 × 2 × 10 = $24,000 of staff time a year. At 3 rounds, it is $36,000.

Your real hours could be far lower. If they are, good news: you don't have this problem, and you can stop here.

Step 4: Fixed fee or hourly?

How that time affects you depends on your contracts.

On fixed-fee (lump-sum) work, every hour spent on paperwork comes out of your margin. Hours saved stay with the firm.
On hourly work, the client may pay for those hours, but the same people can't spend them on other projects. If your utilization looks like the PKF average, capacity is often the real limit.

Know your mix before you decide what saved time is worth to you.

Step 5: Do the same for proposals

Marketing and sales, where proposals sit, is where firms already use AI most. The ACEC and BST Global survey found 81% use in marketing and sales, against 36% in design and project delivery (HPAC, Jun 2025). Time your next proposal or statement of qualifications the same way: research, past-project write-ups, resumes, assembly and principal review.

Compare the two annual figures, and start with the larger one. There is no reason to automate comment letters if proposals are where your time goes, or the other way around.

Step 6: Compare your options

Option	What it costs you	What it changes
Do nothing	Nothing new; the annual figure keeps running	Nothing
A better spreadsheet template	A few hours to set up	Consistency; entry is still manual
A dedicated platform	For example, Nomic Business is $40 per user per month with a 25-seat minimum, so at least $12,000 a year (Nomic pricing, checked Oct 2026)	Strong on drawings and submittals; priced for larger teams
Set up tools you already pay for	Setup and training time	Text drafting with engineer review

For more on each route, see our tool comparison.

A simple decision rule

If logging, matching and drafting take under an hour per letter, don't automate. Fix the template and move on.
If the annual figure matters to your firm, run a small test: one live project, every draft reviewed by an engineer, and time the next three letters.
If the test doesn't save time after three letters, stop. You will have spent little and learned your real number.

Before any test, write down the review routine: who checks each draft and what they record. That is in line with what North Carolina's board asks for, and it makes the test result believable to your partners.

What to bring to the conversation

Whether you talk to us, a software vendor or your own partners, bring three numbers: hours per letter or proposal by role, rounds or proposals per year, and your fixed-fee share. With those, any recommendation can be checked against your own math instead of a vendor's.

Want help filling in the worksheet? Start a free conversation. Bring your rough hours per letter or proposal, and we'll work through the numbers with you.