Staining and Finishing Exterior Doors

[Jon Eckels]

I've got a few screen doors coming up that i'm going to have to stain and finish. They're pine, so they need a good coat of whatever to protect them. I'll be spraying whatever the topcoat is, the stain i'll do by hand.

The stain is going to be a Red Mahogany, for that i'll just use Minwax (unless someone knows of a stain/topcoat combo that's better).

Someone mentioned the Sikkens Cetol Door and Window to me, but I've no experience with Sikkens products in the past, other than knowing that they're expensive. I want something that seals the doors well, as they're going on a relatively high end home.

Please share any advice you may have, thanks.

[jeremy levine]

I've got a few screen doors coming up that i'm going to have to stain and finish. They're pine, so they need a good coat of whatever to protect them. I'll be spraying whatever the topcoat is, the stain i'll do by hand.

The stain is going to be a Red Mahogany, for that i'll just use Minwax (unless someone knows of a stain/topcoat combo that's better).

Someone mentioned the Sikkens Cetol Door and Window to me, but I've no experience with Sikkens products in the past, other than knowing that they're expensive. I want something that seals the doors well, as they're going on a relatively high end home.

Please share any advice you may have, thanks.
I've had some good luck with minwax spar urethane, but it is as thick as a brick from the can.

[Steve Schoene]

You want to be sure that the stain you use is pigment only, without a dye component. The dye part will fade quite rapidly in exterior applications. I don't know the Minwax product, some of there products are pigment only and some include dye. Let the can stand with out disturbing overnight, and put a small wood stick in the can. If only the bottom gets intensely colored, it is pigment only. If the top part is also strongly colored there is dye included and you need to choose another stain.

If you are going for a clear gloss finish, use a good quality marine spar varnish. Minwax isn't on the list. Better products include Interlux Schooner, Epifanes Gloss, and Pettit Captain. These will outlast the Minwax product by several times as long. They are only found at boating supply stores, never at any of the borg.

By the way, lots of varnish is sold too thick these days in order to comply with VOC (Volitile Organic Compound) regulations. Any oil based varnish can, and should, be thinned to a proper brushing consistency. The manufacturers lie about this on the labels, because to tell the customer that the varnish need thinning would be almost the same to the regulators as including the extra thinner in the can.

[Jon Eckels]

I've used McCloskey's Spar Varnish before, for some outdoor furniture that went under a covered porch. Hadn't thought about using it for doors. I could give that a shot too. I was always under the impression that Varnish discolors in direct sunlight.

[Steve Schoene]

The McCloskey's isn't up to marine spar varnish standards either. The UV capabilities of spar varnishes vary dramatically. The three I listed in the previous post have stood head and shoulders above the other spar varnishes for years in Practical Sailor tests, and in the estimation of boaters.

Varnish can yellow over time. Over a dark stain that would be negligable. When a varnish starts to break down, it turns noticably yellow--which comes from the varnish lifting off the wood. To prevent that, a new coat of varnish must be added about every year in full sun, and every couple of years in partial sun. The key is that any dulling is a sign that another coat is required.

Cetol, in my experience, isn't really a superior alternative. It does contain pigment, and may last a bit longer if untreated than varnish if untreated, but in the meantime the cetol I have seen in marine context turns dark and more opaque.

Frankly, the best choice for wood doors, especially made from pine, which isn't a very durable exterior wood to begin with, is paint. A high quality oil based exterior enamel in a lighter shade, being sure that all 6 surfaces are coated with several coats, will outlive any clear or translucent finish. dramatically.

[Jim Becker]

Steve, my understanding is that exterior, oil-based alkyd deep tint base dries clear and is "more durable" than exterior varnishes and a good choice for this kind of application.

[Steve Schoene]

Jim

I have heard that before and read Mr. Kulls posts on another forum, but I am extremely dubious. UV inhibitors are expensive and only small amounts would be needed in a paint, where normally pigment would block light from reaching the wood, or from penetrating into the finish. Why, therefore, would a manufacturer spend money on something that won't improve the performance of the product as it is intended to be sold.

But makers of marine varnish know that UV is the chief enemy and do all they can in UV inhibitors, and in the choice of resins, and formulation to prevent that damage. They have to spend the money or their products will fail. That's also part of why the marine spar costs two or three times as much as the paint base. It all comes under the rubric of "there is no free lunch." These high end marine varnishes dramatically outperform "also ran" spar varnishes in systematic tests such as those performed regularly by Practical Sailor magazine, there is no reason they shouldn't outperform products that aren't even intended to be used as a clear finish.

There undoubtedly are finishing products that outperform the marine spar varnishes on some surfaces, but these will be two part products at perhaps $40 --$65 per quart, some of which are available only to professionals.