A roofing takeoff engine that shows its math
Enter the roof footprint (from drawings or an aerial report) and pitch. Get squares with waste, materials, labor and a bid total, with the math shown. Built to replace the estimating spreadsheet that only one person on the team fully trusts.
Focused Micro-System · ~3 weeks · ~$6,500 · ~3 h ~10 min per quote (client's estimate, not a measured average). Interactive demo uses sample prices; your price list replaces them.
Where roofing estimates usually break
Most commercial roofing estimates still run through a spreadsheet that grew one tab at a time. It works until someone changes a cell.
One broken cell skews the whole takeoff
Pitch multipliers, waste and unit prices live in formulas nobody reviews. One overwritten cell, and the bid is wrong with no warning.
Here: formulas live in code, not in cells. Users enter measurements, not math.
The crew doesn't see what the estimator budgeted
Labor hours are planned in one file and tracked in another, so crew-hour overruns show up weeks after the job is closed out.
Here: the estimate becomes the job budget your field lead sees (in the full system).
Run a takeoff
Change the inputs and open "Show the math" to check every number. Prices are samples; in your system they come from your price list.
This demo prices the field of the roof only. A production estimate also includes flashing, edge metal, penetrations, insulation layers and tear-off.
Build one on your price listRoofGuard Systems: production takeoff & bid generation
Watch how an estimator enters drawings measurements, reviews pitch factors in real time, and exports verified line-item bids with cutting waste buffers.
How the engine calculates
No hidden multipliers or arbitrary guesswork. This is the exact formula behind the commercial roofing takeoff engine.
Pitch factor
√(12² + rise²) ÷ 12
A 7:12 pitch produces a factor of 1.158: every plan square foot yields 1.158 sq ft of actual sloped roof area.
Surface area & squares
area = footprint × factor ÷ 100
Standard roofing units where 1 square equals 100 square feet of surface area.
Squares to order (ceil)
ceil(squares × (1 + waste))
Rounding down means running short on site. The calculation engine strictly rounds material requirements UP.
Materials takeoff
order_squares × material_rate
Calculated based on ordered squares with full waste factor included for membranes, fasteners, and plates.
Labor cost
squares × labor_rate
Labor is priced on installed squares actually mounted by crews on the deck, not on waste scrap.
Client bid total
direct_cost × (1 + markup)
Overhead & profit markup applied directly to total direct costs to protect target contract margins.
What a working system adds
The demo shows the core calculation. A system built for your company covers the full estimate and what happens after it is accepted.
Focused quoting engine
Replaces estimating spreadsheets with a clean, mistake-proof internal calculator tailored to your vendor pricing sheets.
- Your price list with effective dates: Suppliers' prices updated in one place; every estimate locks its historical price snapshot.
- Full line items: Flashing, coping metal, roof drains, pipe boots, insulation boards (ISO), cover boards, tear-off and dump fees.
- Custom waste and labor rules: By system, pitch difficulty, and roof height, rather than one flat multiplier.
- Branded PDF proposal: Generates client-ready bids with scope breakdown, exclusions, and quote expiration dates in seconds.
- Estimate version control: Change scope or materials while retaining the full audit trail of prior revisions.
Typically delivered in 2–4 weeks with fixed price and scope.
Estimating inside your operations system
Connects estimating directly to job site budgets, material procurement, crew labor tracking, and customer invoicing.
- Everything in Focused Quoting, plus:
- Estimate job budget: Accepted quotes automatically convert into warehouse material lists and crew labor budgets.
- Budget vs actual: Foremen record installed squares and hours; estimators see variance patterns on completed jobs.
- Roles & approval gates: Bids below minimum gross margin or exceeding financial thresholds require executive sign-off.
- Two-way software sync: Webhook connections to QuickBooks, JobNimbus, or Procore to sync invoices and job files.
Typically delivered in 6–12 weeks. Exact scope agreed during the audit.
Errors stopped before the bid goes out
Built on poka-yoke (mistake-proofing) engineering principles: system design that makes invalid combinations impossible to submit.
Impossible combinations are blocked
Single-ply membranes (TPO/EPDM) cannot be selected for steep-slope roofs. Out-of-bounds dimensions trigger real-time validation warnings.
Try it in the live demo aboveRounding always goes the safe way
Material rolls, boards, and fasteners round UP to whole units. Financial figures round strictly at the final bid line to avoid fractional leaks.
Try it in the live demo aboveEvery number shows its origin
Unit prices, pitch factors, and markup percentages remain transparent alongside the output. No hidden arbitrary markups.
Try it in the live demo abovePrices cannot silently go stale
Estimates quoting from price sheets older than 30 days trigger an explicit notification before proposal PDFs can be generated.
Automated margin floor
If unexpected site complexity or heavy discounts push gross profit below corporate thresholds, a manager's override is required.
Formulas tested against benchmarks
Automated regression test suites run against a bank of historical reference roofs on every code release so formulas never silently drift.
Simple to run, easy to hand over
Clean relational architecture built on battle-tested web standards. Delivered with full documentation so any qualified engineering team can inspect and maintain it.
| Database Table | Stored Data & Business Rules |
|---|---|
| roof_systems | Roof assembly specs, compatible slope pitch ranges, default waste margins |
| price_lists | Vendor names, supplier sheet version, effective activation date, status |
| price_items | Item SKU, unit of measure, unit cost, foreign key to price list |
| estimates | Customer account, job address, status, assigned estimator, project type |
| estimate_versions | Measurement inputs, calculated totals, price snapshot ID, author, timestamp |
| line_items | Item description, calculated quantities, assembly formula reference, subtotal |
From audit to a working estimator
Predictable fixed-price engagements with no hourly runaway. Every build starts with a structured audit.
Operations Audit
5–7 working days · from $1,000
Workflow bottleneck mapping, clickable core-flow prototype (5–6 screens), and a written fixed-price build specification.
100% credited toward a Custom CRM build if started in 60 days
Bespoke Build
Quoting Engine: $5k–$8k (2–4 wks) · Core CRM (Phase 1): $15k–$35k (6–12 wks)
Software development in your GitHub repository. Live working demos every 1–2 weeks with fast async feedback loops to keep your launch date on track. Complete vendor database integration.
Audit: 100% upfront. AI Workflow and Micro-System: 50% at kickoff, 50% at launch. Custom CRM: 30% at kickoff, 40% at the midpoint demo, 30% at launch.
Cutover & Rollout
Historical verification & training
We test the calculation engine against your past quotes until the numbers match, or every difference is explained.
For 30 days after launch, anything that doesn't work as the agreed spec says is fixed at no cost.
Questions estimators ask
Straightforward answers about custom calculation software, price updates, and technical ownership.
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Want to see this on your own numbers?
Book a 30-minute call. Bring one past estimate spreadsheet — we'll demonstrate how it would run through an engine like this and outline what it would take to build yours.
Prefer email? Reach us at info@solvilab.com