Applying the nasty 5 letter word to Eastern Red Cedar

[jeff...]

No doubt ERC is beautiful fresh off the planer, but it's brilliance soon fades if a finish isn't applied quickly. It turns from a bright red, purple and white to a brownish tint heading on it's way to gray. I have a rather large outdoor ERC project I need to finish. Although I am dead set against stain, I may have to sallow my pride and apply the nasty five letter word in this case.

The way I see it I have two options:

#1 leave it alone and learn to like the gray weathered look.
#2 try and restore the color by:

* Bleaching

* Straining

* Sealing

Question is which stain would be the best to apply, I assume an oil base, but in all honesty I don't follow new breakthroughs for stains very close. What's a good low maintenance stain and sealer for outdoor use?

Thanks

[DIYGUY]

Hey Jeff,
I am unaware of any finish that is impervious to UV. No matter what you use it is going to change color once the sun hits it. Even the varnishes with so-called UV inhibitors inevitably fail to completely block the effects. Consumer Reports did an extensive eval on these several years ago. Some lasted longer than others, but none did the job totally, I would pick a color you can live with and go from there You can count on needing to refresh it every 5-6 years. And yes, oil finishes are preferred for a reason - they last longest. I have always loved Ben Moore products - you won't go wrong if you choose them ...

[FredP]

I think I would learn to live with it but I am lazy! if you use a stain you will prolly want to seal it as well. look forward to resealing every 2-3 years. this carolina sun will beat a finish to death! grey cedar looks rustic!

fred

[RayH]

Jeff,

The LOML and I chose unfinished cedar for an outdoor arbor/bench some years ago for the reason that it did not require constant refurbishment to retain its appearance. We think of it as "gracefully aging". But then, that's how we think of ourselves .

It would not work on some items, but for general appearance, we like it.

If you need a different look, I would suggest an oil product.

Good luck on your project. But when do we see the pictures??

RayH

[Tarhead]

Jeff,
This is hearsay but it sounded good when I heard about it. I've seen references to people using Olympic #5 exterior oil paint base without tint or pigment added for clear exterior finishes like wooden doors. Basically you end up with the protectant features of the paint with a clear/amber finish. I'm thinking Howard Acheson was involved in this discusion on Woodnet. It looks milky when in the can but dries clear. You can buy it this way at Lowe's but you will probably have to talk to them a little as they are convinced they have to sell it pigmented. I've seen the cans on the shelf.

[LeftyTom]

Dave posted a pic of a ERC box he did, and stained it with Waterlox Sealer/Finisher. Waterlox may have something for outdoor use as well.

http://www.ncwoodworker.net/forums/s...light=waterlox

[DaveO]

Waterlox does have a great outdoor oil product
http://www.waterlox.com/desktopmodul...ail.aspx?ct=27 It's high gloss

I really like Penofin products for outdoor projects -
http://www.penofin.com/products_rl.shtml

or this might be better for your application around a pool -
http://www.penofin.com/products_rl.shtml

Any finish in an outdoor environment is going to require renewal at some time. Choosing one that is easy to re-fresh is very smart. Or like Ray said, just let it gray gracefully...like we all will someday.

Dave

[JackLeg]

I have used the Australian Timber Oil by Cabot on a cedar swing that has been outside thru the winter. The finish still looks great. Just apply it as thinly as possible (per their instructions) and it's supposed to have great UV protection also. I think they recommend re-applying every 2 years or so.

I also use this on the cypress outdoor stuff we build with good looking results.

Just my 2 cents worth.

[scsmith42]

Jeff, one of the rules of thumb re stains is that the more pigment in it, the longer it lasts.

I did some research a while back and came to the conclusion that TWP products by Atemco are some of the best available. Texas A&M University's Forest Products Lab did some extensive testing and they ranked TWP very favorably.

This link has some good info re outdoor stains:

http://www.mfgsealants.com/articles.html

Scott

[cskipper]

You can buy Danish Oil with UV protection and I think one for outdoors with UV protection. I have no idea how well they protect and preserve the color of the wood.

[McRabbet]

Jeff,

As Yoda say would: "Stain nasti is..."

[Gofor]

Take this for what it is worth, because I am not a physicist, chemist, or even a college graduate, but I have worked with coatings for over 35 years and done a lot of research and conversed with many of the above chemists, physicists, and PhDs over those years:

Coatings provide protection from the environment and esoteric appeal. For wood, the deteriorating factors are erosion, organics (mold, etc), chemicals (i.e acid rain, exhaust pollution), oxidation, and ultraviolet light.

Components of coatings consist of three main categories: Resin (the binder that holds the coating together when dry, and give it flexibility or brittleness, hardness, toughness, or softness, moisture resistance, and some gloss characteristics); Pigment (the particles that give it color, abrasion resistance, UV resistance, heat resistance and gloss characteristics depending on its leafing qualities); and Solvents (which keep it fluid enough to apply, but leave through evaporation before the coating cures). Sometimes additives such as insecticides are combined with the resin to enhance a particular property.

Curing of coatings is by three main methods by which the resin becomes inert (not necessarily hard): Evaporation (lacquer, shellac, silicon sprays); Oxidation (varnishes, enamels); Catalytic or chemical reaction (epoxies, 2-3 component polyurethanes); or a combination or two or three.

Resin provides resistance from oxidation and moisture as it seals the wood. It is also the compnent that is destroyed most readily by UV.

The pigments provide the UV protection by reflecting the suns rays. If they are fully leaved like flat leaves laying flat on top of each other they give the most reflection (gloss coating). Interleaved means the pigment flakes are somewhat flat and allow light (UV) penetration at different angles (semigloss paint). Open leaved has the pigment flakes standing on end, offering the least reflection and most penetration of UV (Flat paint). Most commercial coatings have mineral pigments as they are the least photochemically reactive to light in their own right (rocks stand up for a while). The only clear/translucent pigment is silica (glass) and it still allows some UV penetration.

Deterioration of a coating comes from the UV deteriorating the resin, allowing the pigments to fall out or be washed away. Gloss, which reflects most light, last longest and flat lasts the least.

Most varnishes (and that includes the "Polyurethane" varnishes) cure by oxidation, and will deteriorate from both oxidation from air exposure that is expedited by UV deterioration. The longer the molecules in the resin (i.e tall-oil or long-oil varnishes), the more resistant to the UV. Spar varnishes are the only long-oil varnishes in the average commercial store. The varnish is the resin.

Bottom line: No 2 coat clear coating will provide UV protection for more than 3-5 years. The 5 year ones are those that contain silica, and the protection factor degrades per year, so some UV damage will be seen.

Pigmented (i.e color type which masks the wood) coatings can provide 10 year+ protection, depending on the pigment. More light reflection, especially in the UV spectrum, and the higher the intial gloss, the longer the coating will last. (i.e white high gloss paint lasts longer than purple or black). There are some silicon based aluminum pigmented coatings that will last longer, but need high temperature to cure enough to be moisture resistant.

This is submitted with the expectation that Howard will correct any misconceptions I have.

I do not know if the color change in cedar is photochemical or oxidation. If oxidation, keeping the moisture away will keep its hue. If photochemical, light will change it regardless. I suspect it is photochemical as is cherry.

Go
.

[scsmith42]

Mark, thanks for the detailed and informative response. I learned a great deal from your post.

Based upon your experiences, can you share some recommendations regarding the best (ie most durable) exterior stain products for wood? Please include products sold commercially, as opposed to only at the local BORG's.

Thanks.

Scott

[Gofor]

Originally Posted by scsmith42

Mark, thanks for the detailed and informative response. I learned a great deal from your post.

Based upon your experiences, can you share some recommendations regarding the best (ie most durable) exterior stain products for wood? Please include products sold commercially, as opposed to only at the local BORG's.

Thanks.

Scott

I have used products made by Phillips, Sherwin Williams, Pittsburg, TWP, Cuprinol and Wohlmans. None lasted more than 3 years in direct sun without significant coating deterioration. (loss of moisture and mildew resistance, pigmented stains were chalking and mostly gone). The Phillips and Sherwin Williams had wood deterioration beginning in that time. The Cuprinol copper based coating (green) for wet wood areas did work well for up to about 7 years. I would say that I had best results from the Pittsburg and Cuprinol .
No transparent coating made it past two years (most were mostly gone after one) and the translucents were only slightly better. (Most of what I used and/or evaluated was in FL and other southern climes (Pacific Islands, Cal, Arizona, NM, La, Texas, etc so some extended life can be expected this far north).
In well shaded areas, there was a lot less chalking, but they still lost a lot of the moisture and mildew resistance.
IMHO, if you want to see the wood grain, plan on recoating every other year in the sun, and every third year in the shade.
If you are going with opaque route, a good quality acrylic latex (the $20+ per gal variety) will provide better and longer protection (about 7 years direct sun and 10+ in the shaded areas) at about the same materials cost, but will require initial priming and 2 coating. Repainting, if done before the wood is showing and water saturated, can be power washed and one coated. An opaque oil-based stain in the high foot-traffic areas on a deck would probably stay more attractive and be easier to refinish than latex, but it will need doing every 3 years or so, depending on exposure. I would not use a floor & deck enamel on an open PT deck, as the moisture from underneath will cause the enamel to peel. I have used the cheap "barn paint" from Lowes on handicap ramps and they are still holding up well after 2+ years, probably because the wood sucked up the paint about as fast as I could apply it.

I have not used Penofin, Rhinogard, Ready Seal, or Cabots. They have gotten good reviews, but all still recommend recoating in 2 -3 years, and I have not heard of them lasting any longer anywhere this far south.

Sorry if this doesn't answer the question, but the word durability and exterior stains have not gone together in my experience..

Go

[scsmith42]

Mark, that's all great info and I appreciate your taking the time to share it. I'll have to experiment some with Pittsburgh and Cuprinol.

Regards,

Scott