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Penetreat Borate Log Preservative FAQ's

Penetreat Borate Log Preservative FAQ's

  • Can I apply Penetreat over my dried out logs?

Penetreat can be applied to log surfaces, whether green or dry, that are bare. As with any substrate application, the surface must be clean. Penetreat will form a protective "shell" on the outer layer of the logs to a depth of about ½”. Keep in mind that, in order for Penetreat to maintain its potency, it must be covered with a good quality stain.

  • Can I mix PeneTreat in with my stain?

No. PeneTreat is designed to be used only underneath a quality coating of some kind.

  • Can I stain over Penetreat?

Yes. In fact, Penetreat has to be covered with stain in order to maintain its potency. Virtually all stains work well when applied over Penetreat.

  • Does Penetreat kill mildew?

No. Mildew is a type of fungi that exists on the surface of wood and does not actually attack or eat wood (although it can cause some discoloration of the wood surface). Penetreat's great strength is its ability to control wood-destroying fungi that actually cause rot. Of course, Penetreat also helps to control many insects, which are killed when they ingest the treated wood. If you want to control mildew, you should use an additional mildewcide in your stain and clear coat. We recommend Stay Clean I/E to kill mildew.

  • How long do I wait after applying PeneTreat before I stain?

The wood must be dry – below 20% moisture level. The only way to verify this is with a moisture meter! We highly recommend that our customers rent or buy a moisture meter to be sure that the wood really is dry before staining. Many times when a stain fails, we find out that it was applied to wet wood that was seemingly “dry enough”.
In a warm and dry climate when there has been no rain, generally 2 days is enough time for the Penetreat to dry before applying stain. However, it is important to note that any liquid that gets on the logs (including mixed Penetreat) can sit in a check or crack in the upper curvature of a log for several days before completely evaporating. While it sits in the check, the water soaks into the surrounding wood and creates localized areas of high moisture content, which can lead to localized areas of failed stain. Therefore, it is best to remove standing water or Penetreat from such areas with a shop-vac, dry rag or compressed air by at least the next day so the adjacent wood can dry out like the rest of the logs in a reasonable amount of time.

  • How often do I have to use Penetreat?

Generally, just once – before the first stain is applied to the wood. However, if that stain is not kept in good condition over the years, then exposed wood can permit some of the Penetreat to leach out when exposed to moisture. In this case, reapplication of Penetreat to bare wood may be required. Penetreat will not penetrate through any coatings, so it must never be applied to stained wood – only bare wood.

  • PeneTreat is a strong wood preservative. Does this mean it is very toxic?

Not when compared to the toxicity of most other wood preservatives historically used. Penetreat is disodium octaborate tetrahydrate. This chemical is very effective at stopping the fungus that causes rot. Also, Penetreat kills most wood boring insects. However, the product is fairly benign to humans and pets (compared to most other fungicides / insecticides). Some skin irritation or eye irritation can occur upon contact – be sure to wash with plenty of water. Also, do not spill a large amount of the solution onto your yard – plants may die if a significant amount is applied to them. Like any product or chemical you use on your log home, use care and common sense when handling. As always, we are happy to supply you with a Material Safety Data sheet for Penetreat, or any of our products, at any time.

  • What are the little white, sparkly crystals on my logs after I applied PeneTreat? How do I get rid of them?

These crystals sometimes appear after the application of Penetreat, especially on newly constructed denser species of wood that don’t allow as penetration of the Penetreat. There is nothing to worry about – the whitish micro-flakes are just the crystallized Penetreat material. You will simply need to brush them off with a stiff brush or broom before you apply stain. Be sure to wear eye and respiratory protection when brushing the crystals from the wood.

  • Why do I need to PeneTreat in this dry climate?

Even in dry climates fungi and insects can attack wood. Roof runoff and ground splash-back can frequently deliver large volumes of water to isolated regions of logs that, without a fungicide in the wood, can succumb to rot. And, of course, wood-boring insects are in all climates, and a defense against them is highly important.

  • Will Penetreat work if there is already stain on the logs?

As with all borate products, the answer is no. In order for PeneTreat to perform its intended function, it has to penetrate into bare, clean wood. If a coating exists on the wood surface, it acts as a barrier to the PeneTreat/water solution, prohibiting penetration and retention.