Skip to main content
Builder.Tools
ToolsPricingFind a BuilderFor TradespeopleBlog
UKUS
Builder.Tools

Practical construction calculators and project tools. 5 tools stay free; the full quotes, jobs and invoices workspace is localized for UK firms.

Tools

  • Calculators
  • AI-Powered
  • Utilities

Company

  • Find a Builder
  • Join Our Network
  • Trade Partners
  • For US Contractors
  • Our Story
  • Blog
  • Help & Support
  • Contact

Legal

  • Terms of Service
  • Privacy Policy
  • Cancellation & Refunds
  • Disclaimer
  • Affiliate Disclosure

© 2026 Builder Tools. All rights reserved.

Need a hand? Help & Support · contact@builder.tools

Built in the UK. Now building for US contractors too.

  1. Home
  2. Tools
  3. Timber Span Check

Timber Span Source Check

Capture the inputs needed for a current timber span-table check and identify when a project-specific structural design is required. No section size is inferred.

How to use the Timber Span Source Check

  1. Choose the jurisdiction, building use, member type and verified timber strength class.
  2. Measure the span between support centres, not merely the clear gap between bearing faces.
  3. Enter the centre-to-centre member spacing and identify altered, damaged, wet or uncertain timber.
  4. Identify point, trimming or uncertain loads so the tool can route the proposal to structural review.
  5. Use the resulting input sheet with the current complete TDUK/TRADA table or a structural engineer; no section is generated here.

Why use this tool

  • Removes untraceable numeric rows and fabricated roof, rafter and heavy-load multipliers.
  • Captures the measurements and conditions needed to consult a current complete span publication correctly.
  • Fails closed and calls for project-specific design where a basic table lookup is inappropriate.

Approved Document A's 2004 edition removed its former timber floor and roof sizing guidance and paragraph 2B1 directs users to separate TRADA tables or recognised structural design standards. Because the current complete numeric tables are not reproduced in the public Approved Document, this tool does not invent a section. A current table must be read with all of its load, service-class, restraint, bearing, deflection, vibration and workmanship notes. Alterations, notches, holes, damage, moisture, concentrated loads, trimmers, openings, change of use and non-domestic work require competent structural assessment.

Part of Builder Tools Calculators — construction tools for UK tradespeople.

Related building tools

  • Cable Lookup
  • Concrete
  • Profit Checker