Cypress or Red Cedar for waterfall/fountain

[Perry Holbrook]

I'm ready to move forward on this outdoor project. It will have a goldfish pond with walls of railroad ties about 30" deep. On one corner I plan to build a waterfall/fountain. The face of the fall will be 52" across at the base, sloping back at about a 60 deg angle until it is 20" across at the top and 48" tall.

I plan to use wooden blocks 2" x 2" x 6" long, laid on the 6"face so the face of the fountain will show end grain. So about 26 blocks across the bottom up to 10 blocks across at the top. Blocks will be staggered in and out and each row will be off set so the joints do not line up. A water tray at the top and at least 1 other tray somewhere on the face. Led lights will complete the look.

I can source 8/4 red cedar or cypress for the blocks. I think I understand that either has about the same tolerance to the water, except the sap wood on the cedar may not be the same as heart wood. I also am concerned if either will change color unevenly as they age, specifically on the edges that will probably not have any/much water flowing over them.

I'm pretty much locked into the idea and if it doesn't last forever, it will be a fun project just the same, but I would appreciate any thoughts on which wood may be best.

Thanks,
Perry

[John K Jordan]

...the sap wood on the cedar may not be the same as heart wood. I also am concerned if either will change color unevenly as they age, specifically on the edges that will probably not have any/much water flowing over them...

I assume you are talking about Eastern Red Cedar. The white sap wood in ERC will definitely decay much faster than the red heartwood. My 80 year old barn has ERC poles set into the ground and those in two corners were exposed to rain for years from a damaged roof. The outside of those two poles were punky and crumbling. An old farmer told me to stick a knife in them and if it hit a hard core the poles were fine. They were, and are still strong after another 12 years.

The problem might be that some ERC does not have a clear boundary between the heart and sapwood - much of what I cut and saw here is what I might called marbled with white and red - I have no idea how that would hold up - would it rot clear through?

cedar_P9064289esc.jpg

I believe constantly wet ERC would in fact turn dark, as I suspect would most other species.

I'd probably try to get osage orange - it's nearly impervious to degrading from moisture. Black Locust is nearly as good and might be easier to find. I would want the heartwood only on any wood for this application.

Here is a table - those with a superscript "a" are "exceptionally" rot resistant:
http://www.plantra.com/Portals/0/doc...st-service.pdf

Oh, and you might be able to find some of the imported woods on the "a" list, for example teak. I understand people who build boats often use it; maybe ask in the Boat Building forum here. Those guys will certainly know what works well in the water!

What about some of that fake plastic wood used for decking? Or perhaps do like they do in zoos - form concrete into shapes with wood grain and bark textures.

JKJ

[Bill Dufour]

You might want to reconsider "fake wood". the linked photos show that Fake wood does not have to look cheap. The exterior "wood" is stained and painted concete. This is from 1927 so I am sure better methods to make concrete into wood exist almost a century latter. This was done for fire resistance which should not be a consideration with your waterfall.
Bill

http://www.architecturerevived.com/a...semite-valley/

[Doug Garson]

How do you plan on keeping the water in? You make no mention of a liner. Will the railway ties be in contact with the water? if they are real ones treated with creosote or other preservatives they will probably kill the fish. Maybe post your idea on a pond building forum and see the reaction.

[Perry Holbrook]

Should have mentioned this project does have a budget. I can get either the cedar or cypress for $2 - 2.50 bd ft from a local sawmill, cypress is kiln dried and I believe she said she had either air dried or KD for the cedar. So exotics or even plastic is off budget. I'll check on black locust at the mill.

Yes pond will have a rubber liner as well as a piece of liner behind the face of the waterfall. Concern about chemicals in the water is why I am not considering pressure treated.

As far as building out of something other than wood, I'm going for the novelty of the idea of a wooden fountain, some who see my work consider me an artist, need to keep up the illusion

Anyone care to make a selection recommendation between my original woods?

Perry

[Pat Barry]

I think the red cedar will look much better than cypress in continuous contact with water. Since the wood will be wet all the time and not drying / wet / drying / wet, I don't think the rot issues are the same. Sure, it won't last forever but it will be cool and should last several years in my estimation. In Minnesota the biggest concern I would have is getting the water drained and dry the blocks out before everything freezes solid for the winter. You may not need to worry about deep freeze in NC

[Andrew Hughes]

Since it's all about the look shouldn't you decide what looks best in person.Both are good as far as rot.Red cedar is actually in the same family as Cypress.

Everyone just calls it cedar because of the smell?

[Darren Duchi]

Sounds like a fun project, in many "exterior woods" there are tannic acids. Tannins leach out of the lumber and create blackish puddles in the winter. Just so you know what to expect.