Handling & safety. No significant health reactions reported beyond standard wood dust risks.
Properties
| Latin name | Picea spp. / Pinus spp. / Abies spp. (mixed) |
|---|---|
| Species type | Softwood |
| Origin | Canada (British Columbia, Alberta, Quebec, Ontario) — exported worldwide |
| Density | 430 kg/m³ |
| Janka hardness | 2,200 N |
| Modulus of rupture | 63 MPa |
| Elastic modulus | 9.5 GPa |
| Crushing strength | 36 MPa |
| Specific gravity | 0.43 |
| Porosity | Non-porous (softwood) |
| Tangential shrinkage | 6.9% |
| Radial shrinkage | 3.5% |
| Volumetric shrinkage | 11.3% |
| T/R ratio | 2 |
| Durability (EN 350) | Class 5 |
Density and mechanical properties are typical values at around 12% moisture content. Shrinkage figures represent total dimensional change from fibre saturation to oven dry. Individual boards vary.
Description
Because it’s a mixed group, individual pieces can vary a bit in density and feel, but the grading system is designed to deliver consistent structural performance. That’s why SPF is a default choice for studs, joists, rafters, wall plates and general timber-frame construction.
Natural durability is low, but SPF usually treats well, so preservative-treated SPF is common for outdoor roles. The key is to think “grade, treatment, and detailing” rather than “species character”—SPF is about reliable engineering supply, not romance.
Anatomy
- Porosity: Non-porous
- Vessel Arrangement: N/A — softwood. SPF group: spruce species (Picea) have small, infrequent resin canals in tangential groups; aspen (Populus) lacks resin canals.
- Vessel Description: N/A — softwood. SPF is a species group: White Spruce (Picea glauca), Black Spruce (Picea mariana), and Quaking Aspen (Populus tremuloides). Spruce species have small, infrequent resin canals sporadically spaced; aspen has no resin canals.
- Parenchyma: Axial parenchyma in uniseriate strands of 2–4 cells; sparse.
- Rays: Uniseriate; ray cells procumbent; typically 1–10 cells high.
Durability
- Durability Class: Class 5 — Perishable
Non-durable. Must be preservative treated for any external or ground-contact use.
Odor
Mild, slightly resinous.
Uses & Availability
Common Uses
CLS studs and framing, joists, rafters, battens, wall plates, timber frame construction, packaging, and general construction. The standard North American construction grade timber.
Pricing & Availability
Widely available in the UK as CLS (Canadian Lumber Standard) dimensioned timber. Pricing fluctuates with global commodity markets and exchange rates. Competes directly with Scandinavian whitewood for UK construction market share.
Conservation
- CITES Status: Unlisted
- IUCN Status: Not Evaluated
Lookalikes & Substitutes
European Whitewood (Norway Spruce) is the direct European equivalent and main competitor in the UK market. Scandinavian redwood for applications requiring more durability.
Working the timber
Easy to work with hand and machine tools. Machines cleanly, sands and finishes well. Takes preservative treatment readily.
Finishing & gluing
Because SPF is a mixed species group, finishing variability is part of the deal: density bands and small resin pockets can make stain look uneven even board-to-board. If you need a uniform coloured finish, sealing + toner/gel stain is usually more predictable than a penetrating stain. For paint, treat it like pale spruce/pine: isolate any knots/pitchy spots and seal end grain to reduce moisture-driven coating failure.
SPF generally glues very easily with PVAs and aliphatic resins because most of the constituent species are low in oily extractives. The main pitfalls are resin pockets and burnished planer surfaces—scuff-sand and de-dust before glue-up for consistent wetting. For structural/outdoor bonds, PU or epoxy adds moisture tolerance and gap-filling, which helps with the inevitable variability in construction-grade stock.