ThermalBrown Lumber  

Pick a Specific In-Stock Unit (great value; generally ships within 10 days)

Currently Available for Online Purchase/RFQ:  

Shop Standard Product Configurations 

(great value and good lead times!)



Rand 4-16'

min: 250 bf

Request Custom Quote 

(additional costs and lead times generally apply)

Don't see what you need? Fill out more generic Request For Quote Form

ThermalBrown Lumber - Product Info

ThermalBrown Lumber is lumber which has been run through a thermal modification process to give it enhanced durability and other characteristics and nice brown tones.

There are 2 main ways for you to purchase ThermalBrown Lumber:

Approach #1: Purchase a barcoded unit of choice from "Pick a Specific In-Stock Unit"
You can see photos and descriptions of various available units and pick the unit(s) that best meet your needs.

Approach #2: Purchase one of our most popular ThermalBrown Lumber options in "Shop Standard Configurations"
Find the product option that is the best match for your application, provide the width(s) and quantities needed, and submit your quote list. If you have other preferences (species, texture, custom color mix, etc), let us know what they are in the comments field and we will take those preferences into consideration (while not guaranteeing that we will be in a position to quote exactly what is requested.) Trestlewood will then email a proposal to you. We will sometimes tweak widths and other characteristics quoted based on inventory units on hand.

Specification Sheet #7230 - ThermalBrown Lumber
SpeciesMixed Species. May include Pines, Firs, Spruce, Larch, Oak, Elm, Hickory, Hemlock, Ash, Maple, Beech, Poplar, Cedar, and/or other species. Generally heavy to (or even exclusively) softwoods unless hardwoods are specifically ordered. Trestlewood can include hardwoods at its discretion. Mixed Species means that any combination of species (including all one species) is allowed.
SourceThermalBrown Lumber is lumber which is run through a thermal modification process. Lumber used in Trestlewood's ThermalBrown Lumber program can be i) lumber reclaimed from various salvage projects, ii) lumber cut from beetle-killed, fire-killed or dead-standing trees, iii) lumber cut from material which has weathered out of spec, and/or iv) new lumber. Lumber which is antique/reclaimed will generally be labeled as such.
Metal/HolesNails and fasteners are generally removed (if they existed in the first place.) ThermalBrown Lumber which comes from new lumber will often not have nail or other fastener holes.
KnotsUnlimited knots; some tight, some loose or fallen out
Checking/CracksUnlimited as long as board is sound
Grain PatternMixed
Moisture Content/StabilityThermally modified to a low moisture content. Thermally modified wood is said to absorb less moisture than normal wood, giving it greater stability. Trestlewood makes no specific claims that in any way attempt to quantify this benefit. Even with thermally modified wood, we take the conservative position that wood is wood and will move. ThermalBrown Lumber can sometimes be stored outside or otherwise exposed to moisture after the thermal modification process.
Standard Dimensionsa) Thickness: 1" (actual: 5/8" to 4/4") and 2" (actual: 1 1/2" to 8/4"); b) Width: random, 4" to 10"; 12" widths are also often available (actual widths can be as much as 3/4" nominal); c) Lengths: 6' to 16'.

Where more consistent thicknesses and/or widths are desired, thickness planing and/or edging processing options are often available. Boards can have small sections that fall outside standard thickness and/or width ranges. Trestlewood will often leave board ends that dip below 5/8" thick (or otherwise fall outside standard dimension ranges) to give the Buyer as much flexibility as possible, but exclude those ends when tallying board footage so as to not charge Buyer for ends that will likely need to be trimmed in the field.
WeightDepends on species mix and other factors. The thermal modification process can cause wood to lose weight. Typically, 2.5-3.5 pounds per board foot.
Surfacing/Texture/ColorsOriginal face was generally rough-sawn (circle-sawn or band-sawn.) ThermalBrown Lumber colors vary, but are generally a range of browns. ThermalBrown Antique Lumber can include any combination of original and fresh-sawn edges (the latter are especially common where narrow boards are cut from wider boards.) Trestlewood generally does not offer a color sort which does not allow for some latitude in colors provided. The ThermalBrown Lumber program typically facilitates greater color consistency than available with Antique Barnwood Lumber.
OdorThermalBrown Lumber often has a "burnt" smell as a result of the thermal modification process.
Appearance VariationBoards 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.
Siding Product ConfigurationsWhen Trestlewood quotes 1,000 square feet of a specific siding configuration, it is quoting enough material to provide 1,000 square feet of coverage based on default installation assumptions and 0% installation falldown. Buyer should order enough product to cover anticipated installation falldown and the impact of any changes to installation assumptions. Siding configuration options include:

(a) Board to Board (common widths: 4", 6", 8", 10", mixed)
(b) Board and Batten (common board widths: 8", 10", 12"; typical batten width: 4"; assumed: installed with 2" gaps between boards)
(c) Board on Board (common widths: 6", 8", 10", mixed; assumed: installed with 1" overlap on each edge)
(d) Shiplap (common face widths: 5", 7", 9" (often actual face widths of 4 3/8" to 4 7/8", 6 3/8" to 6 7/8", 8 3/8" to 8 3/4"); target thickness often between 11/16" and 3/4"+/- for NatureAged/Harbor Fir and between 5/8" and 3/4"+/- for Antique and WeatheredBlend (while Trestlewood will generally target one thickness for a specific batch/order of shiplap lumber, a weathered face shiplap product will naturally have some thickness variation); most commonly, 3/8" shiplap joints are milled on opposite edges and opposite sides of boards)
(e) Wedgelap w/ Rabbet (common face widths: 5" to 5 1/4" (typical actual coverage of 4 1/2" to 4 3/4"), 7" to 7 1/4" (6 1/2" to 6 3/4"), 9" to 9 1/4" (8 1/2" to 8 3/4"); typical thickness of +/- 1/4" on thin side to 3/4" or a bit less on thick side; rabbet added to thick side); stress reliefs are NOT added to the back face; this is a custom product and cannot be returned
(f) Wedgelap w/o Rabbet - this product is typically cut on a resaw and is not as exact (i.e., there will be more variation in dimensions) as Wedgelap with Rabbet. Involves cutting a wedge in as-is lumber (usually 6", 8", or 10" nominal width.) Resulting product will generally have thickness of 1/4"+ to 11/16-7/8" and width of 5.25"+, 7.25"+, or 9.25"+ (with coverage width depending on how installed on site (often 4.5"+/-, 6.5"+/-, 8.5"+/-.) Stress reliefs are NOT added to the back face. Lumber is NOT double end trimmed. The wedgelap without rabbet does not sit as flat on the wall as the wedgelap with rabbet - this likely increases the chances of cupping, splitting, and/or other movement over time. This is a custom product and cannot be returned.
(g) T&G (common face widths: 3", 5", 7", mixed; target thickness often between 11/16" and 3/4"+/- for NatureAged/Harbor Fir and between 5/8" and 3/4"+/- for Antique and WeatheredBlend (while Trestlewood will generally target one thickness for a specific batch/order of T&G lumber, a weathered face T&G product will naturally have some thickness variation); fit of barnwood siding T&G often not quite as good as flooring T&G)

Unmilled siding products (a, b, and c) are standard barnwood lumber. Targeted thicknesses and widths of milled siding products (d, e, f, and g) are generally driven by barnwood lumber inventory on hand. The milling process generally reduces but does not eliminate variation in actual thicknesses and widths (across boards and even within specific boards.) The milling process often creates additional character like loose or fallen out knots. Such defects are generally left in the boards; buyer can decide whether to install them as is, cut them out, or fill them. Kiln drying lumber prior to milling it can increase the tendency for knots to become loose during the milling process. The average length of siding boards (especially milled siding boards) will generally be less (sometimes significantly less) than the average length of lumber boards. Siding square foot prices will generally be somewhat to significantly higher than lumber board foot prices because they reflect more material and, in the case of milled products, additional processing costs.

Trestlewood makes no representations about the fitness of its products for use as siding or in any other application. It is ultimately the Buyer's responsibility to (a) determine which products (and their accompanying characteristics) are acceptable for use on its project and then to (b) make sure these products are handled and installed correctly. While Trestlewood is not a construction or installation expert, it does periodically pass on (without any guarantee of accuracy) information/resources to its customers that it thinks might provide helpful starting points to consider - see, for example, Trestlewood's 6/2/2016 blog post "Thoughts to Consider Prior to Wood Siding Installation" and other blog posts/resources on
OtherThe thermal modification process can give ThermalBrown Lumber characteristics including: (a) increased durability; (b) increased dimensional stability; (c) lighter weight; (d) brown color tones; (e) quicker to weather gray when exposed to sunlight; (f) increased brittleness; (g) lower mechanical/structural strength; (h) burned smell; and (i) etc. ThermalBrown Lumber should not be used in structural applications or in situations involving ground contact.

Trestlewood does not guarantee the existence (or lack) of any characteristic or make any claims about the degree to which the above-listed or any other characteristic may exist in specific ThermalBrown boards.
Note: Please study specification sheets to familiarize yourself with product characteristics and their possible implications for your application.