SpanRef puts residential span tables on pages you can read on a phone at the job, with calculators that run the same numbers backwards. It holds 866 span cells from 4 floor joist, rafter and ceiling joist tables in the residential code, plus 136 from the deck joist and deck beam tables of a deck construction guide.
Who is behind it
An independent developer, working alone, builds and runs SpanRef. The same developer runs AmpSizer, CogoKit, MixRatio and ThreadRef. No engineering firm stands behind any of these pages, and no PE is named on them.
Where the numbers come from
Each span value is transcribed from one of these published tables, and every table page prints its own source line:
- International Code Council: International Residential Code (IRC) 2018, Table R502.3.1(2) - Floor Joist Spans, 40 psf Live Load
- International Code Council: International Residential Code (IRC) 2018, Table R502.3.1(1) - Floor Joist Spans, 30 psf Live Load
- International Code Council: International Residential Code (IRC) 2018, Table R802.4.1(3) - Rafter Spans, 30 psf Ground Snow Load (ceiling not attached, L/180)
- International Code Council: International Residential Code (IRC) 2018, Table R802.5.1(2) - Ceiling Joist Spans, 20 psf Live Load (limited attic storage)
- American Wood Council: DCA6 - Prescriptive Residential Wood Deck Construction Guide 2012, Table 2 (deck joists) and Table 3A (deck beams)
The table pages, the span lookup, the reverse size finder and the deck tool all read that one dataset.
Guides
No carpenter or engineer signs the guides; each one carries the SpanRef name alone, and its page markup records the SpanRef organization as author. The date a guide carries is the day its text last changed.
What this site is not
SpanRef has no affiliation with the International Code Council, the American Wood Council or any lumber grading agency. It cannot see your lumber stamp, your loads, your bearing or whether your jurisdiction has amended the tables, and the locally adopted code and your building official govern the project.
Corrections
If a cell or a guide looks wrong, write to [email protected] with the table and the size. A privacy policy and terms are published alongside.