The top of the corner post on this deck beneath the damaged mitred corner of the handrail was decayed due to an ant infestation in the moist timber.
The base of the post had been encased by a newer concrete slab, making it impossible for the timber to dry. This resulted in excess moisture, which accelerated decay and caused the galvanised saddle to corrode.
Treating these minor problems avoids an expensive post replacement.
Seal the top of the post with timber preservative after dusting to eradicate the ants. Use a two-part exterior filler, scraping it into the damaged area using a spatula. This seals the area from water penetration and discourages pests.
Cut a square in the concrete around the base of the post using an angle grinder with a diamond cutting disc. Leave about 30mm between the cuts and the base of the post. TIP Wear safety glasses, ear muffs and a dust mask when cutting concrete.
Chisel out the waste using a lump hammer and cold chisel until the base of the post and saddle are exposed and the concrete is no longer touching the timber. Cut a drainage line in the concrete so water doesn’t pool and damage the end grain.