Most trades will not publish a price. Here are the ranges, and what moves you within them.
Talk it throughRising Damp Perth arranges damp assessments across Perth metropolitan area.
Nobody can price a damp treatment properly over the phone, because the cost is set by what the wall is made of and how much salt is already in it. A single-skin limestone wall, a double-brick cavity wall and a rendered wall of either are three different jobs. What we can give you is the range these jobs land in around Perth before anyone visits.
The figures below are what damp work costs in Perth, not a national average. Limestone takes injection differently to brick and usually needs more of it, and any wall carrying years of salt needs the render taken back and replaced with something that lets it breathe. That replastering is often the larger half of the bill.
Two things move a Perth quote more than anything else: whether the wall is limestone or brick, and whether someone has already sealed it with a cement render or a plastic paint. Undoing a well-meant repair is common here and it is not free, so the honest range is wider than most sites will admit to.
Prices here assume ground-floor work on an accessible wall. Heritage listing, a shared party wall, or a floor that has to come up will all move the number, and each is common in the suburbs where rising damp is worst. You get a fixed figure after someone has looked at it.
What follows is indicative. Every one of these is a range because the wall decides, not the website.
| Work | Indicative range | What it covers |
|---|---|---|
| Assessment and moisture survey | $250 - $450 | Moisture readings across the affected walls, a look at ground levels and drainage, and a written finding on which of the four common causes you actually have. |
| Chemical damp-proof course, per metre | $180 - $340 | Injected into the mortar course. Limestone generally sits at the upper end because it takes more material to achieve a continuous barrier. |
| Salt-retarding replaster, per square metre | $120 - $260 | Old contaminated render off, breathable system on. Frequently the larger part of the job. |
| Drainage and ground-level correction | $900 - $6,000 | Lowering paving, cutting back garden beds, adding a drain. Where the cause is bridging rather than a failed damp course, this is the fix. |
| Subfloor ventilation improvement | $1,200 - $4,500 | Less common in Perth than Brisbane because fewer homes have a ventilated subfloor, but it applies to the older timber-floored stock. |
Prices are indicative ranges only. Limestone, double brick and rendered walls each cost differently to treat, and every fixed price follows an on-site assessment.
Limestone is more porous and takes more material to form a continuous barrier. Expect the upper end of the per-metre range.
Replastering is frequently the larger half of the bill. A wall caught early may need very little of it.
Cement render or plastic paint has to come off. Removing a previous well-meant repair is common in Perth and is real work.
A listed facade in Mount Lawley or Fremantle limits what can be cut or drilled, and a shared party wall in Highgate means a conversation with a neighbour before a quote is even meaningful.
You can buy the kit. The reason it usually fails is that the diagnosis was wrong, or the salt already in the wall was never removed, so the tide-mark returns through the new plaster. The chemical is the cheap part.
We arrange assessments across the Perth metropolitan area, including:
Rising Damp Perth