Natural Finishes- How They Work


Decked or Decked Out?

Have you seen the beautifully manicured decks, or the gorgeous wooden homes in magazines? 

That’s the look everyone wants!  Do you have natural finished wood siding or decks?

Have you been floored by your deck as it takes you to the cleaners over and over???  Does it feel like you’re getting knocked to the mat as the bills for keeping that naturally finished wood hit you, one blow after another?

Some people refinish their siding or decks every year or two!  Some put on blinders and simply pretend not to see the ugly reality?

If you own a natural finished home you may feel like you’re painted into a corner with no choices!  Every spring you probably say “I love the look of the natural finish on my siding and deck but I can’t stand what it costs me to keep it looking good.  Isn’t there a long term, affordable solution to this maintenance problem?”

Can maintaining your deck or siding in a presentable manner end up being expensive?

You betcha.  Every year there are numerous articles in the painting and decorating trade magazines on how big and profitable the natural wood finishing market is.  If painting contractors can make big money in this market then its costing someone big money.  Guess Who?


Why must we  finish wood?

Exposure to the elements causes the most harm.  Wood is a porous material with a natural tendency to absorb any liquids, not unlike a sponge.  Wind driven rains, freeze/thaw cycles, scorching sunlight, moisture ranging from bone dry to fully saturated - all lead to dramatic expansion and contraction — causing cracks, checks, and raised grain, which in turn lead to accelerated deterioration. 

Horizontal surfaces, like decks, suffer more.  Water lays on them, grease and ash from cook outs coat them, food and drinks are spilled on them, and foot traffic, complete with various abrasives, wears away at them. 

To protect against all of these exposures and to enhance the beauty of wood, we apply either clear wood finishes, semi transparent stains, solid stains or paint.

Why doesn’t the finish last?

First, you need to have a basic understanding of what is in a can of paint or stain.  There a basically four components- Pigments and solids which are the color and the fillers that form the layer that remains on the surface being finished, binders, which is sort of the glue that holds the pigments and solids together when the paint or stain is dry and vehicle- that’s the stuff that transports all of the other stuff from the can, via a brush roller or sprayer, to the surface being painted. 

Although other weather factors certainly have an impact, ultra violet light (or UV) is a main player in the deck coatings failure game.  UV degrades the binders within a coating - leading to ultimate failure through chalking or flaking.  Paint manufacturers learned a long time ago that, by adding pigments and other solid materials to paints and stains, they could achieve increased protection against the effects of UV and increase the dry film thickness of coatings as well.  Since there are no clear solids, this development lead to longer lasting opaque products but did little to help clear or semi transparent finishes which contain limited amounts of pigment or solids. 

Paint jobs completed with adequate caulking of dissimilar materials and high quality paints, applied properly, can last 10 or more years.

Clear Wood Finishes vs. Pigmented Coatings

 Paint and opaque finishes perform very well, although a lot of people prefer clear or semi transparent wood finishes.  These materials enhance the color of the wood and allow the grain, knots or other natural features to remain visible.  As more pigments and solids are added, the clarity of a finish decreases although its UV resistance increases.  In fact, several clear wood finish manufacturers have coined the terms:  “UV blockers and UV absorbers”, to describe pigments and solids.

Lacking pigments or solids, clear wood finishes that are truly clear don’t last long.  The closer the finish comes to being opaque, the longer it will last.  The bottom line is semi transparent stains will outlast clear finishes and solid or opaque stains or paint will outlast the semi transparents.

How to Get the Best Results- 

Ongoing maintenance is a Must.  Keep it clean!!  When you notice water being absorbed into the wood as opposed to “beading up”, like it did when the finish was new – its time to refinish. When that time comes, do not skimp on proper preparation.  It’s paramount to achieving optimum results.  Algae, mildew and mold must be removed prior to refinishing.  Complete pressure washing is absolutely essential.  The added use of wood prep products is even better.  Contrary to popular belief, bleach is not a cleaner.  It can lighten certain stains but makes wood appear “lifeless”.

Whether you’re building new or re-siding your home, try to limit the amount of natural finished wood on the southern elevation (in the northern hemisphere!).  It gets the most UV exposure.  If possible treat each board – front, back, top, bottom and both ends with one or two coats of finish prior to construction. Then finish the wood with a second or third coat, after construction is complete.  Gaps in wood should be caulked to eliminate potential moisture penetration at these points. 

Regardless of new or existing, it is considerably easier and less expensive in the long run, to apply multiple coats at the same time, after prep is complete.  The additional UV absorbers or  blockers will add directly to the longevity of the finish.  Remember, over time, the porosity of any wood will be satisfied- either with a preservative or with water.

 While this multiple coat approach often ends up being more expensive up front, it is virtually always less expensive over a period of time.  Bear in mind that the prep costs decrease in relation to the overall cost as the expense and subsequent longevity of the coating system increases.  This is why, wise consumers look not only at the initial cost per square foot, but at the cost per square foot per year as well!

Weekend Warriors and Consumer Products

A lot of companies who make clear wood finishes put more money into marketing and advertising than they put into the product itself!!!  “It is as simple as 1,2,3 and next year we start all over again!”  

By taking the time to review the Consumer Reports, and consult with professionals who work with these materials, you will find the approach that best suits your needs.

Student Painter or Seasoned Professional?

Check references, find out how long they have been in the trades, what training they have had, how they train their employees, are they part of any professional organizations?

If you hire a plumber or electrician would you consider a “Student Electrician” or College Pro?  Don’t their names indicate what they really are?  Students.  If you want long lasting professional results – hire a professional!!   

If you do your home work before you start the project or hire a contractor it will be much longer before you’re stuck working on your home again!!

 So after all is said and done you do have at least one choice-  you can deck your halls with boughs of holly

 or you can-   bow to your deck and walls with hours of folly!