Reblocking in Bell Park, Corio, Norlane and Lara

Reactive clay and your stumps

Reactive clay changes volume with moisture. In a wet winter it swells and pushes stumps up; in a dry summer it shrinks and lets them drop. Stumps around the outside of the house — where the ground dries and wets fastest — tend to move more than those in the middle, so floors go out of level unevenly. Leaks, pooling stormwater and trees near the house make it worse.

Housing in the north

Norlane and Corio were built out rapidly in the post-war years, with a lot of timber and fibro-clad homes on timber or early concrete stumps. Bell Park and Bell Post Hill have a similar mix. Many of these homes are now due for reblocking, and some older fibro homes contain asbestos cement sheeting — that isn't disturbed by stump replacement, but it matters if base boards or cladding need to come off, and we plan around it.

Designing for clay

• Footings to suit the ground — footing depth and size are designed for reactive clay, not a one-size approach.
• Adjustable steel stumps are worth considering where ongoing seasonal movement is expected, because they can be fine-tuned later.
• Drainage matters — directing downpipes and surface water away from the house reduces the moisture swings that move stumps.

Lara and newer estates

Lara's older homes face the same clay issues. Newer estates are mostly on slabs, where movement shows up as cracking rather than sloping floors — that's an underpinning or engineering question rather than reblocking.