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Internal Wood Stabilizer

Timber Pro UV Internal Wood Stabilizer

A Non Toxic Alternative for Waterproofing Wood …with zero VOC’s and zero hazardous ingredients.

Two initial coats of Internal Wood Stabilizer (IWS) provide PERMANENT protection from water absorption. Permanently protect ecologically sensitive wood projects such as:

  1. Raised bed garden boxes
  2. Wood beehive boxes
  3. Dog houses, birdhouses, or wood cages
  4. Wood docks, decks, fences, or wood bridges
  5. Wood greenhouses
  6. Picnic tables, outdoor wood furniture
  7. Wood or log playground structures
  8. Wood siding, especially in coastal or wet climates
  9. Any other bare untreated exposed wood to be sealed
  10. Fence posts, retaining walls or any other wood that will be in constant contact with moisture.

How does it work?

Internal Wood Stabilizer is a clear watery liquid and must be applied to bare, unsealed, untreated wood intended for outdoor use. IWS absorbs and a chemical reaction occurs when it combines with the free alkali that exists naturally in wood.A waterproof gel forms deep within the pores. The gel hardens to hard silicate-like glass crystals which remain permanently imbedded deep within the wood which becomes so dense it can absorb little to no water. IWS does not wear off, never needs re-application and does not attract dirt and spores.


The IWS does not contain any UV inhibitors so the wood will eventually turn silver in color if exposed to sunlight. Penetrating stains cannot be applied once the wood is treated with IWS, because they will not absorb as intended. Paint, however, is appropriate if desired. IWS will increase paint life by up to 300%.

The Water Test Experiment


The above piece of cedar below was dipped twice in the IWS solution. After drying for three days, it was then submerged 20 inches under water for 90 days. The board was then removed from the water and immediately cut in half. Note how the water only absorbed to a depth of 1/8 of an inch at which point the water penetration was halted by the crystalline glass silicate in the wood pores, evidenced by the light color on the inner portion of the board. The formation of these non-toxic crystals results in 60 to 80% longer wood life in comparison to untreated wood.

Exposed cedar siding will eventually turn silver in some climates yet remain waterproof

Additional Product Information:
Photo Gallery
Internal Wood Stabilizer SDS
Internal Wood Stablizer Brochure – Front
Internal Wood Stablizer Brochure – Back