The English Stone Estimating Engine
How a Minnesota hardscape contractor turned the owner’s estimating judgment into software — so every rep prices every driveway like the owner would, the same day they walk it.
The owner was the estimating department.
Every bid flowed through one person’s spreadsheet, usually at night. The judgment was excellent. The bottleneck was total.
Product catalog
Supplier pricing
Job history
Field notes
Margin rules
Proposal templates
Bids waited for the owner’s evening.
Reps measured, then handed off. The homeowner waited days. The owner lost his nights to arithmetic he’d already done a thousand times.
Bids close the same day.
The rep walks the property, talks through the job, and the engine prices it with the owner’s own rules — before the truck leaves the neighborhood.
The spreadsheet’s judgment, extracted.
Not a price list — the decisions behind the price list. The rules the owner applied without thinking became rules the engine applies every time.
Product_Catalog.json
Labor_Model.md
Margin_Rules.md
Proposal_Template.html
The number I write down is the last step. The estimate really happens while I’m standing in the yard noticing things.
When a rep underprices a job, it’s never the multiplication — it’s a rule they didn’t know existed.
The rep measures and talks. Dimensions, site conditions, access notes, product preferences — captured on the phone, in plain words.
The engine selects products, computes quantities and labor, and applies margin rules — the owner’s spreadsheet logic, running on its own.
A branded proposal renders as HTML for the homeowner’s phone and PDF for the file — and lands where the office expects it.
One walk-through, three surfaces.
The same estimate, seen from the driveway, the office, and the kitchen table.
Driveway, walkway, two granite steps
All lines priced and margin-checked. Scope block generated from the walk-through notes. Ready to send.
Wall height at the engineering threshold
The engine flagged wall height near the limit that changes the build spec — confirm on site before sending.
From a walk-through to a priced document.
What actually happens between the rep’s last measurement and the homeowner’s inbox.
Parse the field notes
Measurements, products, site conditions, and access notes extracted from what the rep captured on site.
Select products
The job’s products chosen from English Stone’s own catalog, the way the owner would spec them.
Compute quantities
Areas, base depths, and cut-pattern waste factors resolved from the measurements.
Estimate labor
Crew-days from the company’s own job history — adjusted for access and site conditions.
Margin check
Any line under the company floor is corrected before the proposal can render — the rule is structural, not a reminder.
ⓘ floor enforced per lineRender & file
The branded proposal renders in both formats and files itself where the office expects it.
Curved walkway, flat waste
an early estimate under-counted cuts
Cut-pattern waste rule
curves now carry their real factor
Supplier prices move
Price-sheet updates flow into the catalog. The rules stay; the numbers refresh under them.
↻ catalog refreshedNew product line
A new paver line onboards as data — reps never learn a new system, the engine just knows it.
↻ catalog extendedEstimates meet reality
Closed jobs get compared against their bids; systematic gaps feed the next round of rule tuning.
↻ rules tunedThe bottleneck became a multiplier.
The owner’s judgment now stands behind every rep on every driveway — without the owner standing behind every estimate.
The rules are their IP
The owner’s estimating judgment, in executable form. It doesn’t retire, and it doesn’t take a night off.
Their catalog, their pricing
Products, labor logic, and margin rules live in the company’s own system — updated as the business moves.
Consistent under pressure
Busy season doesn’t erode discipline. The floor holds on the fortieth bid of the week like the first.
Grows with the company
New reps inherit the owner’s judgment on day one. New products onboard as data, not retraining.
Got estimates eating your evenings?
One conversation. I’ll find the workflow, scope the build, and tell you honestly whether it’s a fit.