If you've ever walked into a lumber yard and seen stacks of smooth, consistently-sized hardwood boards ready to build with, that's S4S lumber — Surfaced 4 Sides. It's the fastest path from lumber pile to finished project, and for many woodworkers, it's exactly what they need.
What Does S4S Mean?
S4S stands for Surfaced 4 Sides. The lumber has been:
- Face jointed and planed: Both broad faces are flat and smooth
- Edge jointed: Both edges are straight, parallel, and smooth
- Sized to dimension: Consistent thickness and width throughout
The result is a board that's ready for joinery right off the rack — no milling required.
S4S vs. Other Surfacing Options
| Surfacing | Faces | Edges | Best For |
|---|---|---|---|
| Rough | As-sawn | As-sawn | Maximum thickness control, board selection |
| S2S | Planed smooth | Rough | Flat reference faces, rip your own width |
| S3S | Planed smooth | One edge straight-ripped | Ready to rip to final width |
| S4S | Planed smooth | Both edges jointed | Ready to build — cut to length and go |
Actual Dimensions of Our S4S Lumber
At Craftsmen Supply Center, our S4S lumber is surfaced to these standards:
Thickness Standards
| Nominal | Actual Thickness |
|---|---|
| 1x (4/4) | 3/4" |
| 5/4x | 1-1/16" |
| 6/4x | 1-1/4" |
| 2x (8/4) | 1-3/4" |
Width Standards
| Nominal Width | Actual Width |
|---|---|
| x2 | 1-1/2" |
| x3 | 2-1/2" |
| x4 | 3-1/2" |
| x6 | 5-1/2" |
| x8 | 7-1/4" |
| x10 | 9-1/4" |
| x12 | 11-1/4" |
Species Available S4S
At Craftsmen Supply Center in Tampa, we stock S4S in:
Hardwoods
- Cherry
- Soft Maple
- Poplar
- Red Oak
- White Oak
- Walnut
- Sapele
Softwoods
- Radiata Pine (Select)
- FJT Primed (finger-jointed, primed for paint)
- Eastern White Pine
Not all species are available in all sizes. Call ahead at (813) 988-4677 if you need something specific.
When S4S Makes Sense
Choose S4S When:
- You don't own a jointer or planer — S4S eliminates the need for milling equipment
- You're on a tight deadline — skip the milling and start building immediately
- Standard dimensions work for your project — 3/4" material is perfect for most cabinets and furniture
- You're building small quantities — the setup time for milling isn't worth it for a few board feet
- You're a beginner — focus on joinery and construction, not lumber preparation
The Storage Advantage: Why Our S4S Stays Flat
Here's something most lumber yards won't tell you: how lumber is stored matters as much as how it's milled.
At Craftsmen Supply Center, we store our S4S and S2S lumber in horizontal racks where boards lay flat. This isn't just for convenience — it actually reduces cupping and warping because the weight of the stack keeps each board flat. The boards hold each other true.
Rough lumber, by contrast, stacks poorly. Without flat reference surfaces, rough boards don't nest together well and tend to move. If you buy rough lumber, keep it tightly bundled until you're ready to mill it — that bundle tension is what keeps it flat.
Sold by the Linear Foot (Not Board Feet)
Our S4S lumber is priced and sold by the linear foot, not by the board foot. Here's the difference:
| Pricing Method | How It Works | Best For |
|---|---|---|
| Linear Foot | Price × length in feet (width & thickness are fixed) | S4S/dimensional lumber where each size has one price |
| Board Foot | Price × volume (nominal thickness × width × length ÷ 144) | Rough lumber where widths and thicknesses vary |
Understanding the Nominal Thickness Rule
Here's something that confuses a lot of people: when calculating board feet, you always use the NOMINAL thickness — never the actual surfaced thickness.
Why? Because surfacing is a service, not a discount. The wood content is the same whether it's rough or surfaced. You're paying for the lumber at its nominal size, plus paying for the surfacing service.
| Lumber | Nominal Thickness | Actual Thickness | Board Feet Use |
|---|---|---|---|
| 4/4 Rough | 1" | 1" (rough) | 1" |
| 4/4 S2S or S4S | 1" | 3/4" (surfaced) | 1" (still!) |
| 8/4 Rough | 2" | 2" (rough) | 2" |
| 8/4 S4S | 2" | 1-3/4" (surfaced) | 2" (still!) |
The wood started at 1" thick. Surfacing removed 1/4" to get it to 3/4". But you're still paying for 1" of wood — the planer didn't make 1/4" of wood disappear, it just moved it (into the dust collector). You pay for surfacing as a service on top of the lumber cost.
Example: Linear Foot vs. Board Foot Pricing
A 1x6 S4S board that's 8 feet long:
- Linear foot pricing: If 1x6 is $4.50/lf, you pay 8 × $4.50 = $36.00
- Board foot pricing: (1" × 5.5" × 96") ÷ 144 = 3.67 BF × price/BF
Note: The board foot calculation uses 1" (nominal), not 0.75" (actual). This is standard industry practice — surfaced lumber has the same board foot content as rough lumber. You're not getting "less wood" because it's surfaced; you're getting the same wood with a surfacing service added.
Linear foot pricing is simpler — you know exactly what you're paying based on the length you need. No calculator required.
Buying S4S at Craftsmen Supply
Our S4S lumber:
- Thicknesses: Primarily 1x (3/4"), with other sizes available
- Custom milling: We can surface most species to your specifications
- Grade: FAS (First and Seconds) — the highest standard hardwood grade
- Pricing: Sold by the linear foot
- Cut to length: Need shorter pieces for transport? We can crosscut
Visit us at 1605 N. 23rd St, Tampa, FL 33605, or call (813) 988-4677 for current stock and pricing.
When to Consider Rough Instead
If you own milling equipment, need specific grain selection, or want to maximize thickness, rough lumber may be the better choice. Our comparison guide breaks down the cost/benefit analysis in detail.