Construction estimating software for specialty subcontractors
For commercial electrical, mechanical and plumbing subcontractors with about 15 to 80 people who bid work to general contractors and keep their estimates, bid log and change orders in Excel and Word. We build one system for all three: bids priced from your own library, a bid log you can trust, won bids turned into job budgets, and change orders tracked against the contract. A typical build costs $8,000 to $25,000 at a fixed price, hosting and support start at $350 a month, and there's no fee per estimator.
Last reviewed: November 5, 2026
What estimators need that spreadsheets handle badly
Subcontractors who bid 100 to 200 jobs a year meet the same problems.
- Every bid starts as a copy of the last one. Each copy carries its own prices, so last year's wire price turns up in this year's number.
- A bid log nobody trusts. Results never get typed in, general contractors are spelled four ways, and nobody can say which ones actually award to you.
- A budget retyped from the estimate. The job starts with a budget that doesn't match what was bid.
- Change orders in Word and email. Approved, pending and disputed amounts are added up by hand at month end, and money is left on the table.
- Forty-page bid invitations. Finding the few things that cost money (bonds, insurance, liquidated damages, night work, alternates) takes an estimator an hour, and missing one is expensive.
A developer who compared 15 contractor tools in 2026 called estimating the most underserved workflow in contractor software.
What we build for a subcontractor
The demo shows each piece working for a fictional electrical subcontractor, Corliss Electric. The library, assemblies and cost codes are your own, so the same system fits mechanical or plumbing work.
- An assembly and unit-cost library: items with material cost and labor units, assemblies built from them, the date and source of every price, and prices older than 90 days flagged for a fresh quote.
- Bids built from quantities and assemblies: lines by area, priced live from the library, with material and sales tax, labor hours at the crew rate, subcontracts, equipment, allowances, overhead, profit and bond. Add and deduct alternates are priced on their own, and each revision after an addendum lists what changed.
- A proposal that reads like a letter on your company's paper, with the base bid in words, alternates, inclusions, exclusions, clarifications and signature lines, as a PDF. The estimate behind it downloads as an Excel workbook.
- A bid board and bid log with win rates by general contractor, by kind of building, by bid size and by quarter, and how far under you the winner was when you lost. The demo's two years of history came in from its old bid log.
- Won bid to job budget: marking a bid won creates the job, with the contract (base bid plus accepted alternates) and a budget by cost code and cost type, at cost.
- Change orders priced from the same library, sent, approved, rejected or disputed, and tracked against the contract. Approval grows the contract and the budget, and a register shows what is waiting and for how long.
- Bid invitations read by AI: the AI reads a general contractor's invitation to bid (a PDF) into a draft bid: dates, scope sections, alternates, the requirements that cost money, and counts it can see, such as a fixture schedule. The estimator checks it beside the PDF and confirms it. It never invents a quantity; anything it can't count is flagged for takeoff.
- Everywhere: export any list to Excel, a history of who changed what, and roles for the owner, estimators, project managers and the office, each with its own home page.
You own all of it: the code, the data and the address.
What it costs, and how long it takes
An estimating system is a fixed-price build, typically $8,000 to $25,000, then hosting and support from $350 a month, however many estimators use it. You see the price in writing before anything starts.
| Blueprint | From $1,500: the written plan and the fixed price for the build, credited in full to it |
|---|---|
| Build | Fixed price per phase; most projects $8,000 to $25,000 |
| Included | The first 3 months of Standard support |
| After that | Support plans from $350 a month, hosting included, month to month |
Your spreadsheets keep running beside the new system until the day you switch, so no bid is missed.
How it compares with the alternatives
| Option | Cost | Fits best when |
|---|---|---|
| Excel templates, one workbook per bid | Time | One estimator, a handful of bids a month |
| Estimating software | Often priced per seat, or quote-only | Your work fits the package's way of estimating |
| A construction platform | Priced by annual construction volume, quoted | You want a large platform and its price fits your volume |
| Rowhouse Systems | $8,000 to $25,000 once, then from $350 a month | You want your own library, bid log and change orders in one system you own, with no seats |
See it working
The demo is Corliss Electric, a fictional electrical subcontractor with two years of bids behind it. Sign in with one click, let the AI read a bid invitation, price a bid from the library, turn a won bid into a job budget, and see which general contractors actually award to you. The data resets every night, so you can't break anything.
Questions
Can it start from our price book and our old estimates?
It starts from your item list and labor units. Your old bid log comes in by import, with its mess cleaned and listed, as the demo's did. Old estimate workbooks stay as files unless you want a set of them brought in.
Will it work for mechanical or plumbing, not just electrical?
Yes. The library, assemblies and cost codes are your own. The demo is electrical only because a demo has to pick one trade.
Does it do takeoff from drawings?
No. Quantities come from your takeoff, on screen or on paper, and are typed or pasted in. A digital takeoff tool can feed it later.
Does it connect to our accounting and job costing?
The budget uses the same cost codes and cost types as job costing, so it exports straight into your accounting system's budget import. Job costing itself, with budget against actual by cost code, can be part of the same system.
What does the AI read, and what does it cost?
Only the documents a person sends it, such as invitations to bid. Every draft waits for a person to confirm it. AI use has a monthly allowance in each support plan; use above it is billed at cost and itemized, never beyond a spending limit you agree in writing.
Can the general contractor see anything?
No. Proposals and change orders go out as PDFs, the way they do today. Nothing is emailed or shared from the system unless you ask for that.
How many people can use it?
As many as you have. There are no seats, and each role sees its own work.
What if our numbers are confidential?
They stay in your own system and your own database, never in a shared one, and you own the code.