Borate Wood Treatments: The "Vaccine" for Your Log Home

Published on | Borate wood treatment How to apply borate to logs Termite prevention log homes Tim-bor Professional | Jim McCain

If you are building a log home or stripping an old one down to bare wood, you have a brief window of opportunity to perform the single most important step in log preservation.

It's not the stain. It's the Borate Treatment.

Think of Borates as a vaccine for your wood. Unlike stain, which sits on the surface, Borates penetrate deep into the fibers, turning the wood itself into a material that insects and fungi cannot eat.

If you skip this step, you are leaving your home defenseless against its two biggest enemies: Subterranean Termites and Wood Rot.

What is a Borate Treatment?

The product we recommend is Tim-bor Professional.

  • The Chemistry: It is a white powder made of Disodium Octaborate Tetrahydrate (DOT). This is a refined borate salt mined from the earth (similar to the Borax used in laundry, but much stronger).

  • The Safety: To mammals (humans, dogs, cats), borates are about as toxic as table salt. But to insects and fungi, they are lethal.

The Science: How It Works

Borates do not repel bugs; they eliminate them. Here is the breakdown of how this natural mineral protects your home.

Why You MUST Apply it to Bare Wood

This is the #1 rule.

Borates are water-soluble. They use water as a vehicle to travel deep into the wood grain.

  • If you apply it over stain: The stain acts as a raincoat. The Borate sits on top and washes off in the next rain. It does nothing.

  • The Correct Method: You must spray it onto raw, porous wood. The dry wood drinks in the water, pulling the Borate salt deep into the center of the log.

The Step-by-Step Application Protocol

1. The Prep (Crucial)

  • Strip it: Remove all old stain, paint, or mill glaze.

  • Dry it: Use a moisture meter. The wood moisture content must be below 20%. If the wood is already saturated with water, it cannot absorb the borate solution.7

2. The Mix

Mix Tim-bor Professional with water at a ratio of 1.5 lbs per gallon. Stir until fully dissolved.

3. The Spray

Use a garden pump sprayer. Saturate the logs until they are soaking wet (dripping).

  • Focus Area: Pay special attention to Log Ends (corners). The "end grain" sucks up moisture like a straw, making it the #1 spot for rot to start. Saturate these ends heavily.

4. The Seal (The Lock)

Because Borates are water-soluble, they can leach out of the wood if exposed to rain over time.

You must seal the Borate in.

Once the wood is dry to the touch (usually 24-48 hours), apply your UV Guard II or SuSTAIN immediately. The stain acts as a waterproof cap, locking the salt inside the wood forever.

4 Common Mistakes to Avoid

We see DIYers make these errors constantly. Don't waste your time and money.

  1. Applying over Sealer: We said it before, but it bears repeating. Borate cannot penetrate stain, paint, or clear coats.

  2. Skipping the Topcoat: If you spray Tim-bor and then leave the logs exposed to rain for a month, the rain will wash the protection right out. You must stain soon after drying.

  3. Ignoring Interior Wood: Borate is safe for interiors. Treating your interior beams protects against Powder Post Beetles, which love dry, indoor wood.

Using "Bug Juice" Instead: Many people confuse Tim-bor with Bug Juice. They are different.

Frequently Asked Questions

Is Borate safe for my pets?

Yes. Borates are inorganic salts. Unless your dog eats a massive amount of the raw powder, it is harmless. Once dissolved and sprayed, it poses virtually no risk to pets or children.

Does it change the color of the wood?

No. When applied correctly, Tim-bor dissolves clear. However, if you mix it too strong, you might see white crystals on the surface after it dries. Simply brush these off with a stiff broom before staining.

Cheap Insurance.

A bucket of Tim-bor costs a fraction of a termite repair bill. Don't build without it.

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