Full Nominal
Actual Dimensions
>19% MC
Green Timber Standard
35-38 lbs/ft³
Green Weight
WCLIB Graded
On Request
NDS Table 4D
Douglas Fir-Larch Design Values
Reference design values for structural timber (5\" and thicker). Apply wet service factor CM = 0.85 for green timber.
| Property | Select Structural | No. 1 | No. 2 |
|---|---|---|---|
| Fb — Bending stress | 1,500 psi | 1,200 psi | 975 psi |
| Ft — Tension parallel to grain | 1,000 psi | 825 psi | 625 psi |
| Fv — Shear parallel to grain | 170 psi | 170 psi | 170 psi |
| Fc⊥ — Compression perpendicular | 625 psi | 625 psi | 625 psi |
| Fc — Compression parallel | 1,150 psi | 1,000 psi | 825 psi |
| E — Modulus of Elasticity | 1,600,000 psi | 1,600,000 psi | 1,300,000 psi |
| Emin — Min. modulus of elasticity | 580,000 psi | 580,000 psi | 470,000 psi |
Source: NDS Supplement Table 4D. Wet service factor (CM): Fb×0.85, Ft×1.0, Fv×0.97, Fc⊥×0.67, Fc×0.8, E×1.0.
Weight Reference
Green Douglas Fir Weight by Size
Based on 35 lbs/ft³ average green weight. Critical for freight quoting, crane planning, and dead load calculations.
| Size | lbs per Lin. Ft | 12 ft piece | 16 ft piece | 20 ft piece | 26 ft piece |
|---|---|---|---|---|---|
| 6x6 | 8.75 lbs | 105 lbs | 140 lbs | 175 lbs | 228 lbs |
| 8x8 | 15.6 lbs | 187 lbs | 249 lbs | 311 lbs | 405 lbs |
| 10x10 | 24.3 lbs | 292 lbs | 389 lbs | 486 lbs | 632 lbs |
| 12x12 | 35 lbs | 420 lbs | 560 lbs | 700 lbs | 910 lbs |
| 14x14 | 47.7 lbs | 572 lbs | 762 lbs | 953 lbs | 1239 lbs |
| 16x16 | 62.2 lbs | 747 lbs | 996 lbs | 1244 lbs | 1618 lbs |
| 20x20 | 97.2 lbs | 1167 lbs | 1556 lbs | 1944 lbs | 2528 lbs |
| 24x24 | 140 lbs | 1680 lbs | 2240 lbs | 2800 lbs | 3640 lbs |
| 30x30 | 218.8 lbs | 2625 lbs | 3500 lbs | 4375 lbs | 5688 lbs |
Complete Q&A
Every Buyer Question, Answered
Green Timber & Moisture
What does 'green' timber mean?
Green timber has not been kiln-dried or air-dried below 19% moisture content. It is heavier, may check (surface crack) as it dries in place, and will shrink slightly in cross-section. For structural use, green timber is standard and acceptable under NDS with appropriate wet service factors (CM factors) applied. Most large-dimension timbers above 6x are only available green because kiln drying at those sizes is commercially rare and prohibitively expensive.
What is the moisture content of your timbers?
Our rough cut timbers are sold green, typically above 19% moisture content and often 40-60% MC for freshly cut wood. This is standard for large-dimension structural timber. If your project requires dried lumber, we can discuss air-drying timelines — though most structural applications specify green timber with appropriate wet service reductions applied.
How much will green timber shrink as it dries?
Douglas Fir has a radial shrinkage of approximately 4.8% and tangential shrinkage of approximately 7.6% from green to oven-dry. In practice, from green to equilibrium moisture content (EMC) in a typical building, expect 1-2% dimensional reduction in each direction. This is accounted for in structural design and is not a defect.
What is the fiber saturation point?
The fiber saturation point (FSP) for Douglas Fir is approximately 28% moisture content. Below the FSP, strength increases as timber dries. This means a green timber will actually gain strength over time as it dries in place — an important consideration for structural applications.
Dimensions & Grading
What are actual vs. nominal dimensions?
Rough cut green timbers are sold at or very near full nominal size — an 8x8 is actually close to 8"x8", unlike surfaced (S4S) lumber which is undersized (a surfaced 8x8 is actually 7.5"x7.5"). This full nominal dimension is a significant structural and value advantage. More wood, more strength, more material per board foot. We publish our actual dimensions for each size — ask us for specifics.
What grades do you produce?
Douglas Fir structural timbers are graded under WCLIB or WWPA rules. We produce: Select Structural (highest strength values, tight knots), No. 1 (standard structural, slightly more character), No. 2 (utility-grade), and ungraded appearance-grade for decorative applications. Grade stamps are available on request for commercial and permitted projects. Most orders are No. 1 or Select Structural.
What is 'Free of Heart Center' (FOH)?
FOH means the pith (center growth rings) of the log is excluded from the cross-section of the timber. Heart-center timbers are prone to more significant checking as the pith dries at a different rate than surrounding wood. FOH timbers check less, look better, and are required for some appearance-grade applications. FOH adds $125/bf to the base price and is available on most sizes.
What is the maximum size timber you can produce?
We can mill timbers up to 30x30 inches in cross-section and 26 feet in length. For custom sizes outside our standard range, or for lengths beyond 26 feet, contact us directly — we can often accommodate with advance lead time.
Checking & Natural Characteristics
Will my timber check (crack)?
Yes. Checking is a normal, expected characteristic of green timber as it dries. Checks are surface cracks that form when the outer wood dries faster than the inner wood, creating differential shrinkage stress. Checking does NOT reduce structural capacity for most applications. ASTM and NDS grading rules account for checking in design values. Set this expectation with clients — educated buyers expect it and understand it.
Are knots a structural concern?
Knots are accounted for in the grading system. Select Structural grade limits knot size and location to ensure maximum design values. No. 1 allows more character including moderate knots that do not affect structural performance. For aesthetic applications, specify Select Structural or discuss your requirements with our team.
What is the natural durability of Douglas Fir?
Douglas Fir heartwood has moderate natural decay resistance. Sapwood has minimal natural resistance. For exterior applications subject to sustained moisture contact (ground contact, water contact), we recommend treatment or protective finishes. For interior structural applications and protected exterior applications, untreated Douglas Fir performs excellently for the life of the structure.
Weight & Freight
How much does green Douglas Fir weigh?
Green Douglas Fir weighs approximately 35-38 lbs per cubic foot. This is critical for freight planning, crane/rigging specifications, and structural dead load calculations. As timber dries in place, weight decreases — dry Douglas Fir weighs approximately 28-30 lbs per cubic foot.
What is FOH pricing for freight purposes?
FOH (Free on Hook) means the timber is available at our mill in Arlington, WA — the buyer arranges pickup or freight from our yard. All of our published pricing is FOH. Freight is quoted separately and depends on total shipment weight, destination, and freight class. We work with established flatbed freight carriers and can help coordinate shipping.
What freight class are structural timbers?
Rough cut structural timbers typically fall under NMFC Class 60 or 70 depending on density and dimensions. We can provide a bill of lading with the appropriate freight class. For large orders (full truckload or flatbed), LTL vs. FTL is a key cost consideration — we can advise based on your order volume.
Applications & Structural
Are your timbers suitable for bridge construction?
Absolutely. Douglas Fir has a long history in timber bridge construction. For highway and vehicular bridges, reference AASHTO LRFD Bridge Design Specifications, Timber section. For pedestrian bridges and agricultural bridges, simpler design standards apply. We can supply timbers in the large dimensions required for bridge stringers, decking, and bents — including 12x12 through 24x24 in standard sections.
What is the difference between Coast and Interior Douglas Fir?
Coast Douglas Fir (grown west of the Cascade Mountains) is denser, stronger, and the preferred structural species worldwide. It has higher NDS design values than Interior Douglas Fir. Our Arlington, WA mill produces Coast Douglas Fir — sourced from the forests of Western Washington. This is the premium product that international buyers specifically seek. When you buy from us, you're getting true Coast DF, not the Interior variety.
Can timbers be used for export?
Yes. We export Douglas Fir timbers internationally. For export, you will typically need a phytosanitary certificate (we can facilitate), and some markets require ISPM 15 heat treatment. Our HS tariff code is 4407.11 for coniferous wood sawn/chipped. We have proximity to Port of Everett and Port of Seattle for container loading. Contact us for FOH export pricing and container load calculations.
Do you offer grade stamps for commercial projects?
Yes. Grade stamps from WCLIB (West Coast Lumber Inspection Bureau) are available on request and are required for many permitted commercial projects. Please specify this requirement when requesting your quote so we can ensure stamped material is included in your order.