Varnishes for Exterior Applications

We see a lot of wooden entrance way doors and it appears that many of them are built and prefinished before being installed. (We can tell ‘cause we know what to look for!)
Doing an in-house factory finish is the best way to finish a doorway because it can be accomplished under ideal conditions, free of dust and dirt.
Our frustration with that method is that most manufacturers use liqueur finishes. These spray-on coatings are wonderful for furniture because they dry clear and are very hard. Manufacturers like them because the dry very quickly too so multiple coats can be applied giving added protection that is simply not possible with a brush and a roller.
In addition, lacquers can be tinted so that a manufacturer can control the colour and the tone of the finish as a one-step process. There are highly skilled crafts-persons in the industry, building and finishing furniture and doors for a diverse market using lacquers.
And we hate lacquer!
The reason is that the advantage of lacquer is also it’s weakness. That hard finish is also brittle. The outside of your home including the doorway expands and contracts continuously as temperatures change, the sun crosses the sky and humidity levels rise and fall. Lacquer is simply not able to flex enough to match the movement of an exterior doorway and will crack faster than other products better suited to exterior applications.
Also, if the manufacturer used a tinted lacquer when finishing the entrance way they most likely skipped the staining part first! Once the lacquer chips and falls off, you can see the bare wood underneath. An otherwise wonderful entranceway can start to look pretty sad prematurely.
We use marine varnishes. Literally, boat varnish.
These products are designed to endure wind, water, sunlight and everything else you’d expect a boat to be subjected to. They work better than lacquer because they dry but remain flexible, as so they are less apt to crack over time.
Marine varnishes come in various sheen levels from satin to high gloss so you can go for the subtle, satin look or the high gloss English-style shine. We can also tint a varnish ever-so slightly, adding additional depth and richness to the final finish.
Marine varnishes can be sprayed on too and that allows us to create a ‘factory’ finish while that door is still hanging on the front of your house.
So now that you’re a convert to our way of doing things, let’s talk more about spraying on varnish as opposed to brushing it on. Spraying as mentioned gives a smooth, even coat on a surface and, “Look Ma”, no brush strokes. Also, spraying on varnish works better in warmer temperatures when it can actually be too hot to apply varnish using a brush.
There are a couple of limitations though. The first is that we must spend more time prepping your home if we use the spray equipment. The problem of overspray, a factor with all spray equipment is that we need to take more time and materials to mask off your house around the work area. And spraying means that each coat of varnish applied in this manner is thinner than one that can be brushed on so we need to put on more coats.
Usually we do three coats when we apply varnish by brush, four when spraying. Since the drying times are the same for both methods, we end up adding at least one day to the schedule so costs go up for application and travel times. We think the extra cost is worth it though because you end up with a much smoother and more visually appealing finish.
We’ve pretty much moved entirely to spraying on varnish now anyway simply because the end result is so much better than the best job we can do with a brush under ideal conditions.