Timber Framers Guild Forums General General Forum Questions Exterior grade beams - best wood species?

i am working on a high end residence that will have some timber framing like elements and will be exposed to weather. these beams also act as the fascia.

what is a nice, tight, even grained wood species with minimal knots that would be best for this? -not going for the rustic look on this one.

any suggestions. - I read that Douglas Fir was a popular choice, but how does this hold up to a wet/humid environment (gulf coast).
teak is out of question, too expensive and color is too dark.

thanks in advance!

Cypress comes to mind for your area, white oak maybe.

port orford cedar?

Douglas Fir, if the sapwood is trimmed off, has decent rot resistance, but turns grey/black when it weathers.

Teak turns silver as it weathers, but is undoubtedly one of the best choices out of all wood species for outdoor exposure. Its high silica content leads to rapid wear on cutting tools. Finding it in suitable dimensions and, as you mentioned, the cost, make it a less viable option in most cases.

If you're on the Gulf Coast your local options are likely Swamp or Pond Cypress, however avoid the second growth material as it does not have a good reputation for rot resistance. Of course, the first growth or reclaimed material is not cheap.

I might suggest your best bet, all things considered, given your criteria, is Ipe. It's from S. America, is available readily, and in larger dimensions and most standard dimensional sizes. Excellent rot resistance however not the easiest wood to work. It is going to be about 15~20% more costly than 2nd growth cypress, however cheaper than the first growth cypress.

Port Orford Cedar might be available at a local lumber yard, often sold as 'White Cedar', but the quality is not the best, knots are to be expected, and it is not available readily in sizes larger than a 3.5" x 3.5". First growth POC is expensive and getting a bit scarce.

Western Red Cedar is very rot resistant, and might be available at a local lumber supplier. Since the elements you describe sound more decorative than structural, WRC (which is pretty weak structurally) might be a good choice. The price however is on par or higher than the Ipe if you're looking for clear tight-grained material.

Finally, reclaimed heart pine or pitch pine, Eastern Live oak, and white oak would be alternatives to consider.

Let us know what you decide on, or if you are able to narrow down the options.

thanks!

I am familiar with Ipe. i call it the poor mans teak. we see it alot in our industry. very nice wood.

i dont think the WRC will work. although the structure is in large part typical stick, there are a few areas where there will be timber frame like construction and will need the beams to support light roof loads. except one area there is a 21' span with one beam supporting a minor section of roof and couple of windows. i have it drawn at 18"x6" in section. as i havent a clue so i shot in the dark. ill leave it to the engineer but i hope i am close.

thanks all

If you require a clear 6"x18" beam @ 21', or thereabouts, your choices in material for that beam will be narrowed considerably.