Thermory BenchMark Thermo-Ash
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We have partnered with Thermory and their line of thermally modified woods, because of their outstanding quality control and expertise that is next to none throughout the thermal modification process. If you have ever worked with White Ash, then you understand what you are getting with thermally modified Ash. It has the same working properties, just without the seasonal movement. Technically, it is slightly harder and less dense than traditional kiln dried Ash, but this isn’t something one notices as you work with it. It can still be milled and joined, and glued, nailed/screwed and finished like Ash. The biggest difference is the color. Instead of the white wood look of Ash, you now have a darker brown color. It will still fade to a silvery gray if desired, or it can be finished and maintained annually to retain the natural color.
And speaking of color, we feature thermally modified Ash throughout our Alpha Cladding lines, because we love its performance, how it takes a finish, texture and wood grain under finish.
Learn More about Thermally Modified Woods
It’s a complex subject, and while not a new technology, the market is full of options and new products every day.
Thermory Benchmark Ash can be used for decking or cladding, and it can be made in a number of profiles for your specific application. Thermo-Ash is rated as Class 1 for 25+ years resistance against decay, so you can trust it for all of your exterior projects. It is available end matched with Thermory’s JEM joint for a seamless and strong connection that does not have to be over a joist. More importantly, this means less waste on the install without having to use longer lengths or trimming based on joist spacing. For more information on JEM joint strength, download the strength test report from Thermory
THERMALLY MODIFIED ASH CHARACTERISTICS
As stated above, if you have worked with Ash, then you know the properties of Thermo-Ash. Most things will be the same, but there are some exciting differences like the tangential and radial movement numbers. Below, you can see how a thermally modified Ash stacks up
| Character | Thermally Modified | Change from KD |
| Bending Strength (MOR) | 1,722,600 lbf/in2 | -1% |
| Stiffness (MOE) | 12,000 lbf/in2 | -20% |
| Hardness (Janka) | 1325 lbf | +1% |
| Specific Gravity | .55 | 0% |
| Weight | 33.6lbs/ft3 | -20% |
| Density | 554 kg/m3 | -12% |
| Radial Shrinkage | .1% | -2% |
| Tangential Shrinkage | .4% | -5% |
Thermory Ash Sizes
Dimensions are specific to the application, and a variety of profiles are available for cladding and decking. We can provide custom milling using any of our thousands of profiles as well as give you a custom finish option to suit your project.
Board lengths for Ash is available from 4 -15.7 ft (1200-4800) mm
Ash Decking
- 1×4
- 1×5
- 1×6
- 5/4 x 4
- 5/4 x 6
- Decking available S4S/E4E or Grooved for fasteners
Ash Cladding
- 1×4 T&G, Nickel Gap
- 1×5 T&G, Nickel Gap
- 1×6 T&G, Nickel Gap
- 1×8 S4S
- 5/4 x 4 & 5/4 x 6 Fluted Profile
Trim Boards
Available as an S4S board with or without JEM end matching
- 1×4, 1×5, 1×6, 1×8″
- 2×4, 2×6
- 5/4×4, 5/4×6
Additional sizes and/or thicknesses may be available for custom jobs. Please inquire about what you have in mind, and we can work with you to provide a solution.
Why Thermory? After searching for the right brand to partner with in the modified wood space, we feel Thermory has the right amount of generational knowledge and expertise to complement our history and high regard for the finest quality products and robust, ethical sourcing practices
