Software for small civil and structural engineering firms

A one- to three-engineer firm lives on referrals: the architect who needs a beam sized for an open kitchen, the remodeler who found a cracked footing, the homeowner whose inspector flagged a leaning retaining wall. Each job is small and fast, and it changes halfway. The architect widens an opening after you've run the numbers, or the contractor builds from last month's sheet. The admin is keeping track of what you quoted, which revision is current and how many hours the changes cost you.

From request to the balance invoice

1. Requests come through your form: structural calcs, foundation evaluation, retaining wall, grading or drainage plan; who the architect or contractor is; the jurisdiction; whether there's a geotechnical report. If they pick foundation evaluation, a conditional question asks what cracking they see and since when, and the form sends them to your booking page.
2. The "Foundation evaluation" meeting type runs 90 minutes with 45 minutes of buffer, and charges the full fee when they book (for example $450). A cancellation at least 48 hours ahead is refunded on its own; you choose that window.
3. For design work, you send a proposal per deliverable: framing calcs, foundation plan, a sheet of details, one round of revisions for architectural changes and your hourly rate for anything after that. A 50% deposit, valid 30 days.
4. The accepted proposal creates a signature request for your services agreement, with the owner and, if a contractor or architect is paying, their representative as a second signer. Spell out how many plan-check responses the fee includes.
5. Hours go on the project's Time Tracking timer, marked billable when they're for changes outside the scope. "Add unbilled time" puts them on the balance invoice as line items.
6. Calcs and sheets go out as PDFs through Document Tracking. When revision B is issued, revoke A's link so nobody builds from it. Submit the permit set from your own files; the tracked link is for the owner, the architect and the contractor.
7. During construction, send the contractor a single-use booking link for each observation visit, and bill the visits on the next invoice.

A typical week

• Monday: an architect you work with accepts the proposal for a two-story addition and pays the 50% deposit by card.
• Tuesday: a paid foundation evaluation at a 1960s ranch house. The 1-hour reminder meant the owner was home to open the crawlspace.
• Wednesday: the architect widens the family-room opening. Three hours of rechecking the header go on the timer as billable.
• Thursday: you issue revision B of the structural sheets and revoke A. The contractor opens the new set that afternoon.
• Friday: the balance invoice goes out with the extra hours as line items, net 30, with reminders on.

All 13 tools, one by one

How a small engineering firm uses each tool, from the first request to getting paid:

• Link in Bio: barely helps when your work comes from architects and contractors; it earns its place after a storm, as one link to your inspection request form you can post in a neighborhood group.
• Short Links: a short link to the request form for your email signature, with a different one per referral partner so the click counts show who sends the most work.
• Forms: the request with project type, jurisdiction, geotech report yes or no, and questions that only show up for foundation evaluations or retaining walls.
• Scheduling: foundation evaluations charged in full at booking with the address required, and a single-use link for each construction observation visit.
• Proposals: a line per deliverable, the number of revision rounds included, your hourly rate for changes, a deposit and an expiration date.
• E-Signatures: the engineering services agreement with the owner and whoever pays, signers in order, with the certificate showing who signed and when.
• Document Tracking: calc packages and structural sheets as tracked PDFs; revoke the superseded revision and see which email addresses opened the current one.
• Screen Recording: a video of up to 5 minutes walking an architect through why a 24-foot opening needs a deeper beam, instead of a fourth phone call.
• Notes & Boards: notes from each site visit and a board of what you're waiting on per project: the geotech report, the truss layout, the architect's revised plans.
• Time Tracking: one project per job, with hours split between the original scope and billable changes, so you can show the architect where the extra fee came from.
• Invoicing: the deposit and balance from the proposal, changes pulled in from unbilled time, and net-30 invoices to contractors with email reminders before and after the due date.
• Expenses: analysis software licenses, license renewal and continuing education, drives to sites and subconsultant fees, each with its receipt.
• Automations: when the agreement is signed, a task on your board to confirm you have the geotech report and the architect's latest plans before you start.

Your PE seal and your state board

SoloWOS E-Signatures is for your contracts. It isn't your professional engineer's seal and doesn't replace your state board's sealing rules, which vary. In Texas, for example, the board's rules have license holders put their seal and signature (or an electronic seal and signature) with the date on the final version of engineering work before it leaves their control, mark preliminary documents with the board's caveat, and show the firm's name and registration number on documents from a registered firm. Check your own board's rules before you share sealed PDFs electronically.

This is general information, not legal advice. Rules vary by state; check yours with a lawyer or your licensing board.

SoloWOS or Harvest: which fits

Choose Harvest or HoneyBook if:

• Your firm only needs timesheets and invoices for several people logging hours across many projects (Harvest's focus), and proposals and bookings live elsewhere.
• You want payment schedules on one invoice or a native mobile app (HoneyBook).

Choose SoloWOS if:

• A job runs from a request form to a paid site visit, a proposal, a signed agreement, revised PDFs and a balance invoice with the extra hours, and you want all of it in one account.
• You need to know which revision the contractor actually opened, and to shut the old one off.
• You're one engineer for $15/month, or up to 3 for $35/month, with nothing priced per seat.

SoloWOS features checked on October 23, 2026. Harvest's free plan was checked on its site on October 17, 2026, and HoneyBook's rows come from its own pages as summarized in our HoneyBook comparison. See Harvest vs SoloWOS for more.

Start with these three

Proposals with your revision policy in the terms, Time Tracking with one project per job, and Document Tracking for revised sheets. Add the paid foundation-evaluation meeting type if you do inspections.

Free tools that help

• Freelance rate calculator for the hourly rate on changes and plan-check responses.
• Project cost calculator to turn hours per deliverable into a fixed fee.
• Billable utilization calculator to see how much of your week is billable.
• Mileage deduction calculator for site visits.
• Invoice late fee calculator for contractors who stretch net 30.

What SoloWOS won't do for a civil engineer

• No structural analysis, modeling or calcs, and no connection to your analysis or CAD software.
• Not a PE seal and no digital-certificate (PKI) signatures on drawings; seal sheets the way your board requires.
• PDFs and images only, up to 25 MB per document. Models stay on your machine.
• No RFI or submittal log beyond a board with due dates, and no construction schedule.
• Reminders go by email only.
• SoloWOS doesn't file taxes, issue 1099s or collect sales tax for you. Invoicing sends the invoice with a pay link (card through your Stripe account) and your other payment details; your accountant or tax software handles the rest.