I am using red oak as edging on tile in a shower stall. I am leaving the wood unstained,unpainted and want to make it water resistant. I had a can of water based urethane but when I spread it on a piece it stayed tacky so I assume the stuff is no good.
So,I need to find a new coating material. Either I buy a new can of water based urethane or use shellac or I don't know what else. What product is best for this application?
Also, how do I remove the tacky urethane? Or can I go right over it?
Jack you couldn't have picked a worse wood for that application. White oak would've been a better choice. You certainly don't want to use shellac as a sealer against water. I think you need to buy some new poly.
Red Oak is "ring porous", meaning it has little tyloses (think straws) that allow water to flow into the wood. in its makeup. So it will be difficult, if not impossible, to seal it such that water won't infiltrate.
Agree also on White oak as a better option, but . Recommend for long term use either wooden boat products such as Epiphanes, or other high end urethanes. Since you (presumably) don't have a UV issue, these coatings should be up to protecting a proper wood such as White Oak, or some of the tropicals.
You're putting wood in an environment that goes from very humid & wet to dry, several times a day. Pretty sure what ever wood you put there, and what ever finish is chosen, you will be regretting it in a few years. Rarely see any kind of finished wood around a tub or shower for a reason. The only wood I have seen would be teak, cedar, or another rot resistant wood, but it is not finished, and used for the floor or seating.
The first thought that came to my mind, besides red oak is not a good choice, is that moisture would seem likely to get behind the trim, creating an environment for mold.
>>Red Oak is "ring porous", meaning it has little tyloses (think straws) that allow water to flow into the wood. in its makeup. So it will be difficult, if not impossible, to seal it such that water won't infiltrate.
To make a clarification and correction, Red Oak is ring porous AND White Oak is ring porous (major pores are in the "early wood" adjacent to the ring boundary).
The terms ring porous, diffuse porous, and semi diffuse porous describe the distribution of pores in the wood, whether open or filled. A wood like cherry is diffuse porous, the pores are spread out more evenly through the entire ring.
Tyloses are what fills the pores in White Oak and prevents water from freely moving through. Pores full of tyloses make White Oak good for whisky barrels, outside furniture, etc. Red Oak pores are not full of tyloses so they are like open soda straws. Both will still decay but White Oak will last longer under the same conditions.
Some species have just and few and scattered tyloses. Other woods like Osage Orange and Black Locust have pores packed full of tyloses - that plus the natural resistance to decay make them great for fence posts. The book "Understanding Wood" by R. Bruce Hoadley have good explanations of this. The online Wood Database is a good resource to learn the properties of specific species. For example, this is the page on White Oak. Look at the "Endgrain" section, it indicates "ring-porous" and "tyloses abundant" and generally describes the appearance of the end grain. Compare to the entry on Red Oak.
