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Community and Q&A

Front and back porch/deck materials

drpepper | Posted in Green Products and Materials on

Love the look at mahogany but my husband refuses to get wood from Brazil.. how green is Ipe (realize it’s still mahogany) and are there other deck materials just as beautiful as mahogany and low maintenance? Just learned about Timbersil but not show how that looks in person? Thanks for your advice!

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  1. Riversong | | #1

    Check out thermally-modified woods, particularly those companies, such as Cambia in NH (, using locally-grown FSC wood, such as yellow Poplar.

  2. J Chesnut | | #2

    Ipe as far as I understand is an exotic import like mahogany. Black walnut is a domestic wood similar to Ipe but difficult to find and expensive.
    Timbersil, glass impregnated wood, looks like wood (framing lumber). Unfinished it should gray over time with sun exposure.
    While purportedly nontoxic and durable it likely takes high heat and pressure to produce so not necessarily a slam dunk 'green' product.
    Just used it on a project but not enough time has passed to tell how well it holds up to the elements.


    I love Timbersil and the test reports on it are extremely compelling but at last check they had still not gotten an ICC ES report to permit use in exterior applications in areas governed by the ICC code.

    I sent repeated letters last winter after meeting CEO Karen Smilek (SP) at the BuildWell conference in Sausalito and to their distributors and don't understand what the hold up is. I did have to explain what an ES report is at one point. great product and I would absolutely love to be allowed to try it in my homes.

    If you are not subject to building inspections you may want to give it a try. It is generally sold through specialty hardwood suppliers.


  4. drpepper | | #4

    Hi Michael,
    Thanks for your response. What is an ICC ES report?
    - Karen

  5. GBA Editor
    Martin Holladay | | #5

    An ICC ES report is an International Code Council Evaluation Service report.

    It is required by manufacturers of products that want to be considered as equivalent to code-required products.

    For example, the code requires builders to install #15 asphalt felt on walls, or an "approved equivalent." If Tyvek wants to prove that it performs as well as asphalt felt, it hires the ICC ES to test the product and to prepare a report. Then the report is used to convince local code officials that Tyvek can be used as an approved equivalent to asphalt felt.

  6. Dan Beideck | | #6

    Just installed a timbersil porch and deck on our house this past week. It looks and feels like "normal" wood and took the stain well. It came with a bit of white powder on the surface. Possibily a result from the glass impregnation process??? We sanded that off before applying the stain. Other than that, it really works like regular wood.

  7. J Chesnut | | #7

    Michael and Martin correct me if I am wrong but I believe an ICC ES report may be required if the Timbersil is used for structural Joists and Beams, but is not required if the Timbersil is used for the decking.
    It would be interesting to compare the environmental impacts of Timbersil (high embodied energy) and Pressure Treated Lumber (chemical concerns). For structural members that are not seen I don't see good arguments yet to move away from Pressure Treated Lumber.

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