Brick mailbox column leaning or crumbling
moderate 2–6 h
Tools: spirit level, pry bar, hammer and cold chisel, trowel and tuck pointer, shovel, wheelbarrow · Materials: type N mortar, fast-setting concrete for a footing, a precast or cast concrete cap, masonry water repellent
Steps
- Put a level on two faces and rock the column gently: a column that moves at the base has a footing or soil problem; one that is solid but crumbling at the top has a water problem.
- Lift off the cap and look inside: a hollow column that holds water and freezes is the usual reason the top courses crumble.
- For a leaning column on a shallow or missing footing, take it down course by course, keeping whole bricks, and dig a footing 45–60 cm (18–24 inches) deep or below your frost line.
- Cast a footing, let it cure for a day, and re-lay the bricks in type N mortar with a level on every course; leave a weep gap at the bottom.
- Repoint any loose joints on a sound column and fit a cap that overhangs the brick by 2–3 cm with a drip edge, bedded in mortar.
- Once cured, brush a breathable water repellent over the whole column so the joints stop soaking up rain.
Stop and call a pro if
- the column is over 1.2 m (4 feet) tall or has a light or electrical feed inside it
- it is within a metre of the road edge, where a struck column is the town's liability question
- bricks are cracked through and you have no matching replacements
Rules in the US: USPS has height and setback rules for curbside mailboxes (41–45 inches to the bottom of the box, 6–8 inches back from the curb) — set the new column to them.
What a pro does that you can't
A mason rebuilds the column plumb on a proper footing with matching brick and a cast cap, and repoints the rest so it sheds water for another few decades.
DIY cost: $40–120 in mortar, concrete and a cap