# Water repellent sealer before primer?



## ExcelPaintingCo (Apr 16, 2011)

I had a follow up call with a potential client and he asked me if I ever use a water repellent sealer before primer on bare wood. The job is an exterior repaint with some spot priming required. He said he heard about it on the web from This Old House. I found this: http://www.hereandthere.org/oldhouse/water-repellent-sealers.html

I usually use a long dry oil primer to spot primer for an exterior repaint. I think the repellents in the water sealer would cause problems. It says on the web site to wait two days before priming to allow the wax to penetrate. Do any of you guys/gals do this? Does it really help?


----------



## TJ Paint (Jun 18, 2009)

naw.


----------



## ROOMINADAY (Mar 20, 2009)

Looks interesting. Somthing I would do on my own stuff 1st to see if it works.


----------



## ExcelPaintingCo (Apr 16, 2011)

Here is a quote from the site:

Although seldom used, paintable water repellents have been proven to add years to the life of paint. Wood that stays dry holds paint longer. Repellents work by penetrating wood and sealing out moisture that works its way through the paint. Some repellents also contain preservatives that fight wood rot. We used Wolman's Zinsser Woodlife Classic.

It seems like if it is proven to add years to the life of paint, then it would not be seldom used.

I thought penetrating oil-primer would also seal out moisture that works its way through paint.


----------



## NACE (May 16, 2008)

The US Forestry service has always recommended a wood stabilizer prior to priming and top coating. California Paints use to make a Wood Stabilizer that was a clear, thin, oil base product. The forestry service did extensive studies using all kinds of systems and exposures and wood that used this system by far lasted the longest. Especially if it was coated on all six sides.


----------



## CApainter (Jun 29, 2007)

NACE said:


> The US Forestry service has always recommended a wood stabilizer prior to priming and top coating. California Paints use to make a Wood Stabilizer that was a clear, thin, oil base product. The forestry service did extensive studies using all kinds of systems and exposures and wood that used this system by far lasted the longest. Especially if it was coated on all six sides.


Thanks for the info NACE. Low and behold, the following link http://inspectapedia.com/BestPractices/Paints_Stains_Exterior.htm describes the USDA FPL's (Forest Products Laboratory) recommendation for WRP's (Water Repellent Preservatives). Scroll to Application of Paints and Solid Stains.


----------



## ProWallGuy (Apr 7, 2007)

I understand the theory of sealing water out, but what if you are sealing water in? Better be sure that would is 100% dry before using I reckon.


----------



## NACE (May 16, 2008)

TJ Paint said:


> naw.


Great point. Yes. Cedar will acclimate to 8-10% moisture content. Check with moisture meter first. Thanks for reminding me.


----------

