As I’ve mentioned in previous posts, I planned to paint the cedar planks on our porch. I made this decision after years of struggling to find an outdoor stain or sealer that would actually work and hold up to the elements. I have tried several brands so far, all available at major local stores. I’ve tried Cabot Australian Timber Oil, Ready Seal and Thompson’s Timber Oil, among others. And every time, the wood looks amazing right after applying the oil.
This is what it looked like right after I applied the Thompson’s Timber Oil.
But so far none of the options I’ve tried have lasted more than a year. After a year the finish washes off and the boards begin to look incredibly dry, gray and rough, and the color is faded and uneven.
Here you can see in more detail how bad the boards look after just one year. The posts are made of PVC panels and therefore easily get dirty. They still look fantastic after a good wash. But the cedar porch boards start to look terrible pretty quickly…
I think I’ve tried a total of five different products so far and this has happened with all of them. None of them persist. In my frustration, I had decided to paint the porch boards with Behr Porch & Patio paint, hoping that I would get at least two or three years of enjoyment out of the paint.
In preparation for priming and painting, I sanded my porch again to prepare it for the new coat. So at the moment things are looking pretty good again. All of the old paint is gone, the gray is gone, the roughness is gone and the cedar boards look fresh and ready to be sealed. And even though I really wasn’t excited about painting them, I thought it was my best option at the time.
But as is often the case, I received several comments on previous posts that made me think about my decision to paint. I got comments like this…
“I would use an oil-based stain and tung oil finish to preserve your beautiful cedar wood. This information is online: To preserve outdoor cedar wood with an oil-based stain and tung oil finish, a penetrating UV color protection stain must be combined with tung oil to form a tough, water-resistant seal. This two-step process penetrates deep into the wood grain to protect against harsh weather and To protect against rot without peeling.”
That sounds great, but I’ve already tried it. Cabot Australian Timber Oil is a combination of three oils, including tung oil, combined with stain. I’ve been there, tried that, and it took a year (if that) before it started looking terrible.
But then I also get comments like this…
“A word of caution: When we bought our house, the deck had just been painted. We’ve only been here a few years and it looks absolutely terrible. The paint is peeling everywhere. We’re not looking forward to the huge task of scraping all the paint off so we can stain it instead.”
And of course that is always the problem when painting wood for outdoor use. The paintwork looks great…until they don’t anymore. Wood likes your breath. It’s constantly expanding and contracting, and even more so when it’s outside. When you paint wood with latex paint, you are essentially covering the wood in plastic. This is fine as long as the coating is in perfect condition. But the moment the finish fails anywhere, even if it’s just a hairline crack, water gets in, seeps into the wood and then has no way to escape. This leaves water trapped in the wood beneath the plastic coating, causing all sorts of problems like rotting wood and peeling paint.
But as I read and researched the best option, I came across something I had never heard of before: pine tar. Pine tar comes from the trunks of pine trees and is harvested by heating the wood by building a fire around it, which reduces the tar’s viscosity and allows it to be harvested from the wood.
If you would like to see the process (on a small scale) of harvesting pine tar, I came across this fascinating video where a man harvests his own pine tar, which he uses to make not only a wood sealant, but also an ointment that can be applied to the skin for cuts and scrapes.
Pine tar has been used to preserve wood for thousands of years, dating back to the Nordic Iron Age when it was used to protect ships and boats. It was used to protect wooden buildings such as the Urnes Stave Church, the oldest and most intricately carved and decorated stave church in Norway, built around 1130 AD.
All of this means that if it worked on the Vikings, I think it will work for my porch too.
Once harvested from the trees, pine tar can be diluted (generally with purified raw linseed oil) and applied with a brush like an oil-based stain. It penetrates deep into the wood and provides natural UV protection while sealing the wood and protecting it from insects, rot, water, etc.
The best thing about pine tar is that it is completely natural. It is solvent-free and contains no petrochemicals and is therefore completely environmentally friendly. And again, it has been used for thousands of years, particularly because it is a natural, long-lasting method of wood preservation.
Pine tar is not as popular and well-known here in the US as it is in other parts of the world like Norway, but there are companies that sell pine tar in the US (or ship it to the US). Pine tar doesn’t have a wide range of colors like traditional stains found at local big box stores, but I found a beautiful dark brown that’s perfect for my porch and the steps to my workshop. It’s from a company called Earth + Flax. The pine tar comes in a container that looks like this…
And the dark brown color looks like this…
After spending about an hour yesterday reading about pine tar, watching the videos on the Earth + Flax Instagram page, and learning all about pine tar, I decided to give it a try. I’ll be the guinea pig for all of us and we’ll see how well this age-old weatherproofing method works for a Central Texas cedar porch.
