If it all comes down to cost, why wouldn't you as a builder, or as a lumber sales professional choose to use or promote a prefinished product over a field applied coating?

 

In an article from Fine Homebuilding in June of 2008, the author refers to the cost of prefinishing vs the cost of field application of coating (for the article from June 2008 in Fine Homebuilding by John Ross, click HERE).  In Ross's article, three coats of prefinish are $3,456 (that is a primer and 2 top-coats) vs the cost for field application for paint and labor starts at $7,000.  Working out the numbers from Ross's article the cost of prefinishing (assuming he is using 1x6 clapboard) is around $0.60 per lineal foot and the cost of a field applied coating equates to around $1.20 per lineal foot.  No doubt, that's a huge difference.  We are not sure there's that big a difference in the prefinish vs field application price today, so let's look at this from today's perspective and consider some REAL prices:

 

To make this as simple as possible, let's assume that the bevel clapboard that John Ross refers to on page 43 of his article is 1x6x16 cedar bevel.  The 5,760 lineal feet is 360 pieces or 2,880 board feet.  If you break down the costs of a three coat pre-finish (one primer with two topcoats) product, you can purchase that combination TODAY for approximately $2,300.  To field apply a primer and two top coats the cost TODAY would be approximately $2,300 (including paint, sundries, and labor and the $2,300 figure for field application is on the low end, as Ross notes, there are other factors that could contribute to a higher cost, we've figured this at the very very low end).  So if this is correct, then the price of prefinish vs field application can be argued that it is nearly equal right?  Wrong, here are the apples to apples comparison of what you get between the two:

 

• BACK-PRIMING:
• Prefinished material all six sides are finished with each coat (primer and both top coats) allowing for a back-prime which is proven to drastically improve the performance of the siding and the coating system.
• Field application only the top coat is coated which could lead to premature failure of the siding and the coating system.

•  SUBSTRATE PROTECTION:
• Prefinished material substrate is protected from UV deterioration and exposure to elements from time of prefinishing in factory environment until the time that the material is installed.
• Field application substrate is not protected until primer and/or top-coat is applied sometimes weeks and months after installation leading to definate UV degradation and exposure to elements.

• YEAR ROUND INSTALLATION:
• Prefinished material can be installed in most weather conditions at any time of the year.  An installer does need to make sure that cut ends and rips in material is re-primed.
• Field application can only be done when the weather is dry and temps are consistently HIGHER than 35 degrees.

• SHRINK LINES
• Since all SIX sides of prefinished material is coated, there will be NO shrink lines should the material acclimate to equilibrium moisture content and shrink.
• There is a possibility for shrink lines since the material is only coated on the EXPOSED face.

At the end of the day even if the dollar to dollar cost of prefinishing versus field application is the same, the apple to apple comparison of what you get is very different.  There are so many more reasons to use and specify prefinish.  Field applied coatings should only be used to touch-up once a prefinished job has been installed and the weather conditions are favorable.  If you are trying to sell quality products or trying to build a better home - specify prefinished products.