Specification Sheet #1228 - Trestlewood II Circle-Sawn Resawn Slabs

Douglas Fir

Piling of Lucin Cutoff Railroad Trestle--Great Salt Lake

Some boards have occasional 1" diameter holes where metal has been removed. Such holes are generally surrounded by streaking black stains.

Unlimited; occasional loose or fallen out knots

Unlimited as long as board is sound

Mixed

Water saturated (often with significant air drying)

a) Thickness: TWII C-S Resawn Slabs are resawn to 1" thickness. The amount of wane varies from piece to piece, from slight wane to very significant wane; b) Width: primarily 4" and 6"; and c) Length: 2' increments, primarily up to 16'.

Typically, approximately 4 pounds per board foot

Circle-Sawn (either freshsawn (brownish tones) or Weathered (grayish tones)) with wane which varies from piece to piece.

Trestlewood contains significant amounts of salt and other minerals (often 20%+ by weight), creating special characteristics and/or considerations like those described in the following items.

Colors found in Trestlewood II include yellows, oranges, reds, browns, greens, grays/blacks and purples. The coloring of individual boards varies widely, from normal Douglas Fir coloring to color combinations unique to Trestlewood II. Surfacing and finishes impact final coloring. Color variations are more noticeable in planed and milled products than in circle-sawn or band-sawn products. Weathered Resawn Slabs will have a weathered grayish appearance.

Certain finishes and glues do not work well with Trestlewood II. Most importantly, DO NOT USE WATER-BASED FINISHES. We tend to favor penetrating oil finishes on non-kiln-dried Trestlewood II lumber and other non-kiln-dried Trestlewood II products because they allow the wood to breathe, thereby facilitating efficient air drying.

Schuller International performed an ASTM E-84 Flame Spread test on a Trestlewood II piling sample in January, 1995. The resulting index value was 16, well below the maximum index value of 25 for a Class I fire retardant. Normal Douglas Fir has a flame spread index of 70 to 100. Only a few wood species have flame spread index values less than 75. Fire retardant treatments are generally necessary to meet Class I (and often to meet Class II.)

Trestlewood II can have a corrosive effect on metal fasteners, machinery and saw blades. High grade stainless steel fasteners should be used in lieu of regular steel fasteners, especially in applications involving the likely mixing of Trestlewood II, moisture and oxygen.

Trestlewood II C-S Resawn Slabs are not a kiln-dried product--they should not be used in applications requiring kiln-dried wood. Air drying Trestlewood II boards can reduce their moisture content over time, but this tends to be a slow process given that Trestlewood II gives up moisture more grudgingly (and absorbs moisture more readily) than typical Douglas Fir. The salt in Trestlewood II makes moisture meter readings unreliable. Trestlewood II products should only be used in humid environments after you have carefully considered Trestlewood II characteristics and the implications of those characteristics for your application.

Wet Trestlewood II boards often have a Great Salt Lake and/or "musty" smell to them. This odor is especially strong as wet boards are being cut or otherwise processed. It tends to become less and less of an issue as boards are allowed to air dry. Our experience suggests that a Trestlewood II odor is most likely to be noticeable in situations involving moisture or high humidity; limited ventilation / air circulation; and/or uncoated/unsealed Trestlewood II products. We believe the most important step in minimizing Trestlewood II odor issues is to control moisture by facilitating the efficient air drying of non-kiln-dried Trestlewood II products and minimizing any reintroduction of moisture.

As moisture is drawn out of Trestlewood II boards, it brings salt with it. Salt leaching tends to be the most concentrated at knots and board ends, but can happen anywhere. Drying Trestlewood II boards (and keeping them dry) minimizes, but does not eliminate, salt leaching. Approaches to salt leaching include sanding and refinishing impacted areas to doing nothing (and letting the salt serve as one of the most visible evidences of the history and reclaimed nature of Trestlewood II timbers.) Salt is more visible on planed and milled products than on circle-sawn or band-sawn products.

Boards can vary in appearance from piece to piece and even within a piece. The characteristics described on this specification sheet generally apply to each board's featured face. The opposite face and edges can differ from the featured face in texture, coloring, and other characteristics unless otherwise noted. Weathered lumber / barnwood will have at least one weathered face. The opposite face and edges can be any combination of weathered and fresh-sawn. If weathered, the weathering will often be different (amount, mix of colors, etc) than on the featured face.

Trestlewood sometimes uses one or more juicing processes to help fresh-sawn and/or less weathered/aged faces/edges blend in with weathered faces/edges. All else being equal, juicing is more likely to be used in situations where (a) lumber is cut from timbers or wider lumber (thereby creating fresh-cut faces and/or edges); (b) Buyer wants all (or most) faces/edges to be weathered/aged; (c) Buyer desires to increase the consistency of the weathered/aged look from face to face; and/or (d) Buyer wants a darker weathered look.

See the current Trestlewood II Features/Issues summary for additional information about Trestlewood II characteristics and their practical implications. This summary is for informational purposes only and is not a part of the Trestlewood II Circle-Sawn Boards specification sheet.