Covering letter and conditions
Invitation to Tender
A structured covering letter with the issuer, tender deadlines, return requirements and separate tender conditions.
AI-Powered Tender Preparation & Comparison
OneSpec
One clear schedule. Multiple builders. Comparable quotes.
For homeowners, architects, designers and building professionals. Create a structured Schedule of Works & Specification from your building plans and project requirements, so contractors price the same scope and you can compare quotations fairly.
Do It Yourself
Use our intelligent software to prepare your Schedule of Works and compare builders’ quotes.
Create My Schedule of WorksProfessionally managed
Done For You
Upload your plans and let our construction team manage tender preparation and comparison.
Let OneSpec Handle ItThe problem
Three builders. Three different prices. But are they quoting for the same work?
Most homeowners send drawings to a few builders and get back quotes that vary by tens of thousands of pounds. One includes the kitchen, one doesn't. One allows for steel, another leaves it as "TBC".
Without a shared Schedule of Works, you can't tell whether the cheapest quote is good value or simply missing work, and those gaps become extras halfway through the build.
Illustrative figures, fictional builders and project.
Builder A
£68,400
Excludes drainage and decoration
Builder B
£91,250
Includes kitchen fit and steels
Builder C
£74,900
Provisional sums for windows
Construction experience. Intelligent technology.
Two builders can price the same drawings and arrive at very different figures, not simply because one is cheaper, but because they may have included different work. OneSpec helps you define the scope before tendering and understand the differences when quotations come back.
AI helps us work efficiently. Experienced construction professionals make the important decisions. Managed documents require human approval before release; no savings, accuracy or statutory compliance are guaranteed.
See an example Tender Comparison ReportExample tender package
See Exactly What You’ll Receive
One fictional extension. One shared scope. Three builder returns with differences made visible.
20 trade sections
Schedule of Works & Specification
A detailed, descriptive scope with drawing references and source labels.
Blank builder prices
Schedule of Works, Builder Pricing
Complete the blank prices and section totals to return a Priced Schedule of Works.
Three fictional builders
Tender Comparison Report
Fictional returns showing price gaps, provisional sums and questions to resolve.
Illustrative examples, not live quotations or a contractor recommendation. No registration required.
How it works
From drawings to a tender-ready Schedule of Works
Upload your drawings
Plans, elevations, sections and structural details are read and organised into a drawing register.
Answer a guided interview
Plain-English questions capture your choices, and flag anything the drawings don't confirm.
Issue one Schedule of Works
Export a branded Schedule of Works across 20 trade sections, ready to send to every builder.
Why homeowners use OneSpec
Comparable quotes
Every builder prices the same scope, item by item.
No invented detail
Gaps are flagged as clarifications, never guessed.
Fewer surprise extras
Inclusions, exclusions and provisional sums are explicit.
Builders welcome it
Clear tenders are quicker to price, and free to receive.
Simple, per-project pricing
A fraction of the cost of one overlooked extra.
Specification Only
£69
per project, incl. VAT
A clear, trade-by-trade Schedule of Works & Specification you can send to any builder.
- Drawing upload and AI analysis
- Adaptive project requirements interview
- Editable Schedule of Works (20 trade sections)
- Branded PDF export with drawing register
Most popular
Complete Tender
£149
per project, incl. VAT
Everything in Specification Only, prepared for issue to multiple builders.
- Everything in Specification Only
- Tender Readiness review
- Clarification tracking before issue
- Revision history for every reissue
- Side-by-side Tender Comparison Report
- Priced Schedule of Works, quotation uploads and AI feedback
- Downloadable Tender Comparison Report PDF
Expert Reviewed
From £349
per project, incl. VAT
A construction professional checks your Schedule of Works before it goes out.
- Everything in Complete Tender Package
- Human review by an experienced professional
- Written comments on risks and gaps
- One round of reasonable amendments
- Professional review summary
Fully Managed
Done For You
From £795
per project, incl. VAT
Our construction team manages preparation and comparison for a typical domestic extension.
- Project assessment and drawing review
- Professionally checked Schedule of Works
- Tender documents and up to three nominated builders
- One tender clarification round
- Team-checked Tender Comparison Report
- 30-minute online consultation
All consumer prices include VAT. Managed fees are subject to assessment. Payments are not active.