Floor Joist Span Calculator

Joist size/spacing feasibility and count for a floor span under a given live load.

Free tier eligible — 500 calls/month with a free key from /pricing; x402 pay-per-call above quota.

Parameters

Parameter	Type	Required	Description
`span`	number	required	Clear span in feet
`room_width`	number	required	Room width (joist run) in feet
`spacing_in`	number	optional	Joist spacing on-center in inches (default 16)
`species`	string	optional	Lumber species/grade group
`grade`	string	optional	Lumber grade
`live_load_psf`	number	optional	Live load in psf (default 40)

Call it over MCP (JSON-RPC 2.0)

curl -s https://wingmanprotocol.com/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -d '{"jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": {"name": "floor_joist", "arguments": {"span": 100, "room_width": 12}}}'

Or plain HTTP

curl -s https://wingmanprotocol.com/tools/floor_joist \
  -H 'Content-Type: application/json' \
  -d '{"span": 100, "room_width": 12}'

Try it live

Edit the JSON and run it — this POSTs to https://wingmanprotocol.com/tools/floor_joist from your browser.

This tool is x402-metered — agents pay per call with USDC on Base. The 402 response below is the standard x402 payment-requirements envelope: sign the EIP-3009 authorization and retry with the X-Payment header, or get a free key at /pricing (500 calls/month, no card, no crypto).