If the wet patch sits at the height of the ground outside rather than near the floor, the water is not rising. It is being pushed through.
Talk it throughRising Damp Newcastle arranges damp assessments across Newcastle and the Hunter.
Rising damp stops where evaporation catches up with capillary rise, which puts the tide-mark low and level. Lateral damp has no such limit — it appears wherever the retained soil sits against the wall, so a patch a metre and a half up, or a band that follows the line of a driveway, is telling you something different.
Almost always where the ground has been cut into. The terrace and cottage suburbs run over gentle rises, and a century of adding driveways, garages and levelled yards has left a lot of walls retaining soil they were never built to retain. A brick wall standing in open air can dry both faces. The same wall with a metre of wet ground behind it cannot.
Rear lanes are the other common one. Where a lane has been resurfaced repeatedly the ground behind a terrace can sit well above the internal floor level, and every downpour puts water against the back wall at height.
A damp-proof course is a horizontal barrier. It stops water climbing from below. It has no bearing at all on water arriving horizontally a metre further up, which is why being quoted an injected course for lateral damp is a sign the diagnosis was rushed.
Relieving the water behind the wall, then tanking the wet face. That usually means a drain at the base of the retained ground and a barrier system applied to the earth-facing side where it can be reached. Where it cannot be reached, the work is done from inside and the wall is managed rather than cured — which is an honest thing to be told before you spend money, not after.
These are the ranges we see quoted around Newcastle. They are wide on purpose. A single-skin cottage wall in Lambton and a double-brick party wall in Cooks Hill are the same line on this table and nowhere near the same job.
| Work | Indicative range | What it covers |
|---|---|---|
| Assessment and moisture survey | $250 - $450 | Readings taken at intervals up each affected wall, an external check of levels, lanes and downpipes, and a written finding. Where there is cracking it also says whether you should be calling Subsidence Advisory NSW instead. |
| Chemical damp-proof course, per metre | $170 - $330 | Injected into the mortar course. A shared terrace wall sits at the upper end because of access and because it can only be worked from one side. |
| Salt-retarding replaster, per square metre | $120 - $260 | Contaminated render off, breathable system on. Near the water this is rarely optional — the southerly loads the wall with salt from outside while the damp loads it from within. |
| Drainage and ground-level correction | $900 - $6,000 | Dropping a path, cutting a bed back, taking a downpipe away from the wall. On the terraces this often means the rear lane, where decades of resurfacing have raised the ground against the back wall. |
| Subfloor ventilation improvement | $1,200 - $4,500 | For the timber-floored cottages, where a closed subfloor holds moisture under the house. |
Prices are indicative ranges only. A terrace with a shared wall, a heritage-listed facade and an ordinary inter-war cottage all cost differently to treat, and every fixed price follows an on-site assessment.
We arrange assessments across Newcastle and the lower Hunter, including:
Rising Damp Newcastle