Topic Options
Rate This Topic
#33865 - 07/20/16 01:41 PM Building a Simple Arbor in the Pacific NW?
victoremusic Offline
Member

Registered: 07/19/16
Posts: 3
Loc: Whidbey Island, WA
So, where to start.
I've done a couple of traditional (scribe) timber framing projects in northern New Mexico. I'm currently in Washington, and going to build a (relatively) simple Arbor.

So here are some questions I have about building in this area, as well as any feedback on the over all design.

1. I've had mix feedback about building with Cedar if it's less than 50 years old. Supposedly it's not as rot resistant? therefor not as highly recommended. Does that mean I could get away with Doug Fir?
2. The design I'm working with, is very simple, and with a Japanese influence. Any feedback on the sheer strength (see photo's below). Should I add more braces?
3. What sort of sealer is recommended for exterior exposed timbers? This will be traditional style joinery, so I'm concerned about the joints holding moisture in this oh so wet climate.

I am new to this forum,(hopefully that photo works) and must say I am enjoying the abundance of information I'm finding. Many thanks to anyone reading this, and for any feedback.

Vic

Rough dimensions: 12' x 5' foot print
7' 6" at the highest point. All 6x6.





Edited by victoremusic (07/20/16 01:50 PM)
_________________________
ďIf you donít have time to do it right, when will you have time to do it over?"

Top
#33866 - 07/20/16 04:57 PM Re: Building a Simple Arbor in the Pacific NW? [Re: victoremusic]
Jay White Cloud Offline
Member

Registered: 11/06/08
Posts: 480
Loc: Vermont
Hi Vic!

Welcome Aboard...Hope you have a great time here... grin

Quote:
1. I've had mix feedback about building with Cedar if it's less than 50 years old. Supposedly it's not as rot resistant? therefor not as highly recommended. Does that mean I could get away with Doug Fir?


Well...??...there are regional differences with every species. Some say Cherry (Gen. Prunus) is "rot resistant" yet statistically, and through the historic record (for most regions) it typically is not resistant all...often less or the same as a White Pine ssp.

So, with your local "Cedar" (aka Juniperus, Calocedrus, Cupressus, Thuja, Chamaecyparis ssp...as the only true "Cedars" [Cedrus ssp] are found from the Mediterranean to Western Himalayan Region) so even a "new growth" variety will most likely be more rot resistant that a Douglas Fir. In general, of the species of wood you do have available to you...one of your "False Cedars" ssp will most likely yield the best results comparatively to others.

Now this is not to say you could not employ Douglas Fir or some other species. It all depends on how you are going to construct the Arbor, and what other methods are employed to mitigate potential rot. I am not sure if this is going to be some form of direct burial or other system The following are typically for least durable to most...which generically follows buried in soil (least durable)...concrete (which traps moisture and also promotes decay...chard, oiled and buried in gravel...or...above grade and fastened to stone?

Quote:
2. The design I'm working with, is very simple, and with a Japanese influence. Any feedback on the shear strength (see photo's below). Should I add more braces?


Overall the design looks nice...

If going for an "Asian" aesthetic, such as a Torri system there are additional "horizontal" bracing beams called "Nuki" that could be added to the design to further strengthen the frame.

Quote:
3. What sort of sealer is recommended for exterior exposed timbers? This will be traditional style joinery, so I'm concerned about the joints holding moisture in this oh so wet climate.


Traditional "garden" or "exposed" structures of this type are not "sealed"...on average all they receive is a really fine planing with a sharp tool and at best a natural oil blend...of some flax, tung, citrus, pine tar, oils, rosin and perhaps some beeswax. Joinery for exterior work can (and often was) design internally to shed water and/or some of the members would receive a copper or stone shrouding...

Hope that helped some.

Regards,

j

P.S. Love the quote at the bottom...Simply outstanding!
_________________________
http://about.me/tosatomo

Top
#33867 - 07/21/16 01:28 PM Re: Building a Simple Arbor in the Pacific NW? [Re: victoremusic]
victoremusic Offline
Member

Registered: 07/19/16
Posts: 3
Loc: Whidbey Island, WA
Wow, Jay thank you for your in depth response. Much appreciated.

So, it looks like I've got some research and learning to do on the species of Cedar here. I have been given a contact in my area, where I might be able to get old growth reclaimed Cedar, that would ideally be all heartwood. Which sounds promising, but I will do more research to better understand the species that I'm working with.

As far as how it will be attached, there are 10" diameter footers already in the ground (from the prior arbor) that have 3 1/2" x 9" ( 1/4" thick ) metal straps in the center. Someone recommended to me setting the post on a 1/4" plastic (ABS) piece, propping up the post 1/4" off the footer, so that it doesn't wick any moisture, and that pooled up water cannot travel up the post, or into the end grain.

I am doing some redesign now, with a focus on eliminating possible joints that can collect water. Will post more on that as that progresses.

I really like the copper shroud idea, and feel it could add a nice aesthetic (and longevity.) I don't have the tools (yet...) to give it a traditional hand tool finish. I will smooth it to the best of my ability, given the tools I have available, and am looking for the best exterior sealer that isn't overly toxic...yet affordable.

From what I'm told about building in this climate....is that it's only a matter of time before it breaks down. But would like to extend that time as much as I can, without loading it with chemicals. I was just recommended Osmo. Any feedback on that?

Thank you again for all your advice!
_________________________
ďIf you donít have time to do it right, when will you have time to do it over?"

Top

Moderator:  Jim Rogers, mdfinc, Paul Freeman 
Newest Members
Redtop, Stu, HFR, Flange, Phillip_Anthony
4775 Registered Users