Lumber · Form 04 · surfacing
S2S, S3S, S4S.
Surfacing is how much of the milling we do before the board reaches you — how many of its four sides come off the planer dressed, and how many stay rough for you to work. Three states, drawn here at the board’s end section.
S2SSurfaced two sides
Both faces run through the planer to a flat, even, consistent thickness; the two edges stay as the saw left them. The most stock, the most flexibility — you rip and dimension the edges yourself.
S3STwo sides + one edge
S2S plus one edge straight-line ripped to a true reference — the edge you register against a fence or a fellow board. The opposite edge stays rough for you to rip to final width.
S4SSurfaced four sides
Four sides dressed — two flat faces and two square, parallel edges. Ready to work: cut to length and build. The least fuss, the least stock left to remove.
Rough is nominal.
A board’s size is named in the rough — 4/4, 5/4, 6/4, 8/4, in quarter-inches. Surfacing removes stock to reach flat and smooth, so the dressed thickness always lands under the nominal. This is the single most common surprise in ordering hardwood, so here it is drawn to scale, with the whole table below.
| Nominal | Rough | ≈ After S4S |
|---|---|---|
| 4/4 | 1 IN | ≈ 13/16 IN |
| 5/4 | 1 1/4 IN | ≈ 1 1/16 IN |
| 6/4 | 1 1/2 IN | ≈ 1 5/16 IN |
| 8/4 | 2 IN | ≈ 1 3/4 IN |
| TYPICAL — EXACT FINISH DEPENDS ON HOW FLAT THE ROUGH BOARD STARTED · YOU ORDER AND PAY BY ROUGH BOARD FEET | ||
Common questions
What do S2S, S3S, and S4S mean?
S2S is surfaced two sides — both faces planed flat and parallel, edges left rough. S3S adds one straight-line-ripped reference edge. S4S is surfaced four sides — two faces and two square, parallel edges, ready to work.
Why is my 8/4 board only about 1 3/4 inches thick?
Because surfacing removes stock, and rough sizes are nominal. 8/4 means 2 inches in the rough; dressing both faces to flat and smooth takes it to roughly 1 3/4 inches. 4/4 lands near 13/16, 5/4 near 1 1/16, 6/4 near 1 5/16. Exact finish depends on how flat the rough board started.
Which surfacing should I order?
S4S if you want dressed stock ready to build with. S2S if you'd rather keep maximum width and rip your own edges. S3S when you want one true reference edge but will rip the width yourself.
How is the lumber priced?
By the rough board foot — length × width × thickness at the rough size, divided by 144, times the species rate. Surfacing doesn't change the board footage you pay for. Minimum order 100 board feet; freight is quoted to your dock at checkout.
Order milled stock
Every species on the spectrum, S2S through S4S, 4/4 through 8/4, priced live by the rough board foot — freight quoted to your dock.