Floor Sanding Capel Sound

Capel Sound was Rosebud West until 2017, and the housing stock still reads that way — postwar beach shacks with newer coastal infill filling the gaps between them. The shacks are the interesting part. They were built quickly, cheaply and close to the ground, often with minimal footings and subfloor clearances that would not pass anything today, and that construction decision is still setting the terms for every floor sanding job here seventy years later.

Low clearance means poor ventilation, and poor ventilation means a subfloor that stays damp through winter and never fully dries in summer. Damp soil evaporates moisture upward, the underside of the floorboards absorbs it, and the top face — drying in the heated air of the room — does not. The board expands more at the bottom than the top and curls upward at both edges. That is cupping, and across a room it produces a floor that rolls underfoot with a ridge at every joint.

The trap is sanding it flat while it is still wet. Cut the raised edges off a cupped board and the board is permanently narrower at its shoulders. When the subfloor eventually dries and the timber relaxes back toward flat, the centres rise above the edges that are no longer there. That is crowning, and it is worse than the original defect because correcting it means another full cut into timber that has already lost thickness. On a seventy-year-old shack floor there may not be another cut available.

So the sequence matters more than the sanding. We take pin-type moisture readings across multiple points of the floor rather than one spot near the door, and above 14 to 16 per cent we stop. Then we look at why. In Capel Sound the answer is almost always the same: sand and garden build-up has buried the perimeter vents, or there were never enough of them, and the ground under the house has no vapour barrier at all.

Fixing that is not expensive and it is not our work. Clearing buried vents is a weekend. Adding mechanical subfloor ventilation fans is a straightforward trade job. Laying continuous polyethylene sheet across the soil under the house is the single most effective intervention and costs a fraction of a second sanding job. We will tell you which of those the subfloor actually needs, and then we will wait for the timber to come back to a stable moisture content before we cut anything.

That conversation costs us jobs and we have made our peace with it. A contractor without a moisture meter will quote the sand, do the sand, invoice, and be gone long before the crowning appears the following summer. There is no way to compete with that on price, only on whether the floor is still flat in three years.

The floors themselves are worth the patience. Postwar shack construction used narrow-strip native hardwood or wide Baltic Pine laid straight over bearers, and where the timber has been under carpet or lino since the sixties it has been protected from UV and wear. Once the subfloor is sorted and the boards have stabilised, these sand up as genuinely good floors — original, uncut and full-thickness in a way that far more expensive houses often are not.

Capel Sound sits in the Mount Eliza pricing band at $55 to $80 per square metre turn-key, with typical 90 to 140 square metre scopes putting whole-job contracts between $6,050 and $8,800. Legacy adhesive removal where lino was glued directly to the boards adds $10 to $20 per square metre and is common here. Board replacement, where a section has been damaged by long-term damp rather than just cupped by it, runs $8 to $20 per square metre or from $50 a board.

Gap treatment needs mentioning because a floor that has cycled through decades of moisture change has usually opened up. On wide Baltic Pine we do not use rigid resin filler — the boards move too much across their width and the filler gets crushed and ejected the first humid summer. Open gaps cleaned out properly, or tapered pine splines glued in and sanded flush, at $5 to $15 per square metre. On the narrower hardwood strip, a wood-flour resin mix is stable enough to hold.

Coating recommendation is two-pack waterborne, satin. Non-yellowing keeps a pale floor pale under strong coastal light, high abrasion resistance handles the sand tracked in from the foreshore, VOCs stay under 27 grams per litre and the household is back on the floor within 24 hours. On a shack conversion where there is nowhere else to go, that re-entry window is not a luxury.

Three to four days on site for a standard Capel Sound scope, assuming the moisture reading has cleared and the subfloor work is done. If it has not, we would rather move the booking than proceed — and we will say so at quote stage rather than on the morning of day one. Getting a floor like this right is mostly a question of doing things in the correct order, and the sanding is the last step, not the first.