Wood rot is a fact of life when working on boats. Smith's Clear Penetrating Epoxy Sealer (CPES) is the best product available for treating wood rot. A thin epoxy, it is also ideal for sealing wood either as an end, or in preparation for painting. It also seals concrete, mortar, and other consolidated porous materials.
CPES is an essential component for the effective treatment of osmosis blisters on fiberglass hulls.
On wood in good condition, Smith's Clear Penetrating Epoxy Sealer can be used as a stand-alone sealer. It is also an excellent adhesion promoter/primer for paint and varnish.
Complete sealing is generally achieved in just one treatment. With a reputation as, "the cure for paint failure", Smith's Epoxy Sealer is an ideal undercoat on plywood, building siding, etc.
For treating and restoring rotted wood, however, you need to use both components of Smith's wood restoration system:
After removing the observable rotted wood, use Smith's Penetrating Epoxy Sealer to seal the wood and solidify any remaining rot. Then apply Smith's Filler Epoxy to fill the voids left when you cleaned out the crumbly rotted wood. Finally, apply a final coat of Penetrating Epoxy Sealer as an adhesion promoter for subsequent paint coatings. See Related Products, below.
Smith's Clear Penetrating Epoxy Sealer (CPES) consists of a tough, flexible resin system in a solvent blend that dissolves the sap, oil and moisture found in wood. Made from natural wood resins, the epoxy develops a chemical bond to the wood fibers, strengthening them - while still allowing normal expansion and contraction with changes in temperature and humidity.
When repairing wood that has dry rot, the thin-as-water CPES will migrate along the abnormal porosity created by the fungus which causes dry rot. Impregnation of wood with CPES changes the cellulose of wood (which fungi and bacteria find easily digestible) into epoxy-impregnated cellulose which resists further attack by fungi and bacteria while reinforcing the wood - thus accomplishing the restoration.
Paint or varnish applied to the repaired wood will last longer because they have a strongly attached, chemically compatible surface on which to bond.
Not limited to boats, Smith's Penetrating Epoxy Sealer is also ideal for repairing and restoring wood rot in homes, basements, garages, barns, and other structures.
• Longer working time than other epoxies allows maximal wood penetration
• Exhibits toughness and flexibility comparable to the original wood - it moves with the wood
• Allows wood to continue breathing - so it doesn't trap moisture under the surface
• Treated wood is highly resistant to a re-occurrence of dry rot
• Sealer ensures the adhesion of a wide variety of varnishes, paints, adhesives and caulking to the substrate wood
• Clean-Up Solvent will dissolve and clean-up sealer while still wet; see Related Products, below
• Filler Epoxy for re-building rotted sections is high strength, light weight, non-sagging, and easily sanded
• Filler Epoxy must be used over a coat of the Penetrating Sealer to ensure the strongest bond
• The moisture content of treated wood must be less than 20% so as to not overwhelm the moisture absorbing capabilities of the sealer resin
To prevent the re-occurrence of rot, an epoxy sealer must move and flex with the wood - so it doesn't crack and allow moisture to enter. It must also breathe, so it doesn't trap moisture beneath the surface - an environment where fungal spores can grow and produce new rot.
Smith's Penetrating Epoxy does both.
Heavy on the technical side...
Using Smith's, the restoration process for rotted wood is simple and easy to do in six easy steps:
1) Remove any old paint or coatings and dry the wood. (Moisture content must be <20%, and the dryer the better)
2) Remove crumbly, rotten wood
3) Saturate the wood with CPES - the Penetrating Epoxy Sealer, and allow to cure - takes 24 hours to one week depending on how deep the rot went
4) Apply the Smith's Filler Epoxy - let it cure overnight
5) Sand the cured Filler Epoxy to shape
6) Apply one more coat of Penetrating Epoxy Sealer as an adhesion promoter for subsequent paint coatings
Traditionally, the remedy for peeling paint consisted of scrape, putty and paint, and in a few years scrape, putty and paint again.
Contaminated by fungal spores in the air, no one realized that bond failure and paint peeling was the result of the wood rotting in a thin layer just underneath the paint.
Peeling paint increased dramatically in the 1950s, when lead oxide (a white pigment) was removed from primers and paints due to growing health concerns. There was no substitute available; and without this mild but effective preservative, even good-quality wood began to rot sooner.
Furthermore, the faster grown wood used in residential and commercial building construction a few decades later had much of its natural rot resistance bred out of it by the lumber companies - whose focus was entirely on making more lumber, regardless of the quality of the wood.
Even the best paints were failing sooner on wood with little rot resistance.
So, there was an abundance of failure and a complete absence of effective solutions — until Steve Smith developed his modern and effective penetrating epoxy technology in the 1980s.
Steve Smith, a chemist by profession, made a point of identifying the causes of wood rot and paint-on-wood failure — which turned out to be certain species of fungus and bacteria, whose spores are spread in the air. Smith's Penetrating Epoxy utilizes a unique solvent and resin system to attack these fungi and bacteria as no other product does.
Wood naturally contains water, typically 8% to 15%, even 25% in humid environments such as around boats or in chronically humid climates. The solvent system that carries the resins of Smith's Clear Penetrating Epoxy Sealer into the wood has to be capable of dissolving that water, so penetration can occur. Penetrating epoxies made using water-repellent petrochemicals such as benzyl alcohol cannot do this. None of Smith's products use benzyl alcohol.
Thin as water, the solvents in CPES not only dissolve moisture in the wood, they also dissolve sap and oils — allowing the epoxy to gain access to the wood's xylem tubes, along which it flows deep into the wood.
Rot-causing fungi and bacteria produce additional porosity in the wood which is especially penetrable by Smith's Penetrating Epoxy Sealer.
Formulated from natural tree resins, wood impregnated with Smith's epoxy has a toughness and flexibility comparable to the original wood — allowing normal expansion and contraction with changes in temperature and humidity. This helps maintain the bond between epoxy and wood, preventing cracks which would allow water and fungus spores to enter.
Application of CPES changes the cellulose of wood (which fungi and bacteria find easily digestible) into epoxy-impregnated cellulose which resists further attack by fungi and bacteria while reinforcing the wood, accomplishing restoration.
Paint or varnish applied to the repaired wood will last longer because it has a strongly attached, chemically compatible surface on which to bond.
The long working time (pot life) of CPES means it will retain its penetrating and moisture-dissolving ability for more time.
Read and follow application instructions. Keep rain or dew away from areas being treated with CPES until solvents have evaporated out of the wood. This will take at least a day and may take a week or more, depending on the extent of deterioration, how deeply the CPES soaked in and the temperatures day and night.
Application may be by brush, roller or immersion. Spraying is not recommended as a portion of the solvent component will evaporate in transit, and it is important that the product be applied to the wood in the same formulation as furnished originally.
When applying by roller on a vertical surface, orient roller so it is horizontal and slowly roll only in the upward direction.
When treating rot inside sound wood, drill a hole that intersects the rot, glue a funnel in the hole, and use Smith's super thin Cold Weather Formula to impregnate the region. Allow sufficient time for solvents to diffuse and evaporate out of the wood before applying fillers or glues. Removing paint from all sides of wood to be treated speeds the solvent evaporation, as does moving air.
CPES can also consolidate crumbly concrete, and old mortar between bricks.
Smith's Epoxy Cleanup Solvent will clean up any epoxy product before it cures. Once cured, no clean-up solvent is effective.