Step 03 · Repair
Insect & Rot Treatment (Borate)
A borate preservative applied to bare logs to guard against rot fungi and wood-boring insects, including carpenter bees, beetles and ants.
What it is
Borate is a mineral-based wood preservative. Applied to bare logs, it soaks into the outer layer of wood and makes it inhospitable to the fungi that cause rot and to wood-boring insects like carpenter bees, powderpost beetles and carpenter ants.
The timing is what matters. Borate can’t get through stain, so the best time to treat is during a restoration, after stripping and before anything else goes on. That’s why it’s part of the Repair step in our process: we treat while the wood is bare and we can see every repair area, log end and bottom course.
Because borates can wash out of unprotected wood, they’re always sealed under a breathable finish system afterward.
Signs you need it
When to call about borate treatment
- Small round holes in logs, especially on the south side
- Sawdust (frass) piles on decks or the ground near walls
- Carpenter bees hovering around eaves and log ends
- Woodpecker damage, often a sign of insects inside
- Previous rot repairs, or areas that stay damp
- The logs are already stripped bare for refinishing
How Cardi does it
Our method
- 01
Confirm what’s there
We identify the likely insect or rot problem during inspection. Active infestations of some species call for a licensed pest professional, and we’ll tell you if yours does.
- 02
Treat bare, clean wood
Borates absorb into raw wood, not through finish. We apply after stripping and before sealing and staining, when the logs can take it in.
- 03
Apply at label rate
The borate solution is applied at the manufacturer’s rate, with extra on log ends, bottom courses and repair areas where risk is highest.
- 04
Dry and finish
Borates stay in wood, but they can leach out with water, so the treated logs are sealed in under the new finish system once they’re dry.
Where it fits
Borate treatment is part of step 03: Repair
Bare wood is the one chance to see and treat everything. Rot and insect damage left under a fresh finish keep spreading out of sight.
FAQ
Borate treatment questions
Is borate safe around my family and pets?
Borate preservatives have low toxicity to people and pets compared with many alternatives, which is one reason they’re widely used on log homes. We follow label directions and keep people and pets away during application.
Will borate get rid of the bees I have now?
Borate helps deter wood-boring insects in treated wood, but it isn’t an instant fix for an active nest. We may recommend a pest professional for active infestations, then treat and seal to stop them coming back.
Can borate go on over my existing stain?
Not effectively. Borates need bare wood to absorb. That’s why we apply it during a restoration, after stripping.
Related services
Usually done alongside
Media Blasting
Strips failed stain, paint and gray UV damage off logs with a crushed media, without the gouging and fuzzing that harsh methods leave behind.
Learn more Step 03 · RepairLog Rot Repair
Finds soft wood, cuts it back to sound log and rebuilds it with consolidants, fillers or wood patches shaped to match.
Learn more Step 05 · ProtectStaining & Topcoats
Breathable, log-specific stain and topcoat systems, color-tested on your logs and applied to the right film thickness.
Learn moreBook an inspection
Book a borate treatment inspection
That’s what the inspection is for. It’s free, it’s in writing, and it breaks the house down wall by wall, so you can decide what to do now and what can wait.