demotek
estimating and takeoff for demolition contractors
a full estimating platform — measure plans in the browser, price scopes against real assemblies, and ship a branded proposal the same day.
the problem
demolition estimating still runs on spreadsheets and printed plans. a single bid can take a week, and the number at the bottom is only as good as the least careful cell in the sheet.
the work is genuinely hard to model: scopes overlap, crews and disposal are priced by completely different units, and every change ripples through the whole estimate.
the approach
everything is a node in a graph. takeoffs feed assemblies, assemblies feed crews and disposal, and the bid total is just the last node in the chain. change a measurement and the whole estimate re-solves.
the editor is the product. it runs entirely in the browser against a typed api on cloudflare workers, so it is fast everywhere without a server per region.
what i built
the whole thing, end to end — the plan viewer and measurement tools, the circuit-graph estimator, the api and its permission model, and the marketing site.
built with
typescript · react · hono · cloudflare workers · postgres