Much of Pakenham, Officer and the surrounding district is built on reactive clay. Clay swells when it gets wet and shrinks as it dries, so footings and slabs move a little with the seasons. Most homes cope, but the movement often shows as cracks. This guide is general information; if you’re worried, have a builder or structural engineer inspect.

Where cracks usually appear

• Diagonally from the corners of doors and windows
• Along cornices where walls meet ceilings
• At plasterboard joints
• In grout lines and tiles
• Between skirting and floor

Usually cosmetic

• Hairline cracks under about 1 mm
• Cracks that open and close a little with the seasons
• Cornice gaps in new homes during the first couple of years

These can be patched with flexible fillers and tape, then painted.

Get advice

• Cracks wider than a few millimetres, or growing quickly
• Cracks wider at one end than the other
• Stepped cracks in external brickwork
• Doors and windows that suddenly jam
• Floors that slope or sag noticeably
• Cracks in new homes still under builder’s warranty

In these cases, contact your builder or a structural engineer before patching, and keep photos with dates.

Reducing movement

• Keep garden watering even through the year
• Make sure downpipes discharge into drains, not against the slab
• Fix leaking taps and pipes promptly (a plumber’s job)
• Avoid planting large trees close to the house
• Don’t let water pond against footings

Tracking a crack

Mark the ends of a crack with a pencil and date, and measure the width. Check every month or two. A crack that’s stable or seasonal is usually cosmetic; a growing one needs a professional.

How we can help

We patch cosmetic cracks, re-fix popped screws, adjust sticking doors and replace cracked grout and silicone. See plaster and wall patching and door repairs, or get a free quote.