Stopping Rising Damp the Smart Way

Rising damp occurs when ground water travels upward through masonry via capillary action. In Australia’s climate, this leads to tide marks, salt deposits, blistering paint, crumbling plaster and long‑term masonry decay.

The National Construction Code (NCC) requires masonry walls to be detailed to prevent rising damp and moisture ingress, protecting both the structure and the inhabitants. In Victoria, where the NCC is fully adopted, builders and renovators face increasing scrutiny around moisture management.

What is Damp Course Cream and how does it work?

Tech‑Dry Damp Course Cream is a water‑based, zero‑VOC silane/siloxane cream designed to create a new damp‑proof course (DPC) inside existing masonry walls. When injected into the mortar bed, it:

• slowly diffuses into the mortar and adjacent masonry
• reacts to form a permanent polysiloxane barrier
• blocks rising damp while still allowing the wall to breathe

Because it’s odourless, solvent‑free and non‑hazardous, it’s ideal for occupied homes, heritage buildings and interior remedial work.

Is Damp Course Cream compliant with the NCC?

Yes—while the NCC doesn’t mandate specific brands, it requires that masonry walls include a continuous, durable DPC capable of resisting rising damp. Damp Course Cream aligns with NCC expectations because it:

• can be installed at the correct DPC height
• forms a continuous barrier through the full wall thickness
• provides long‑term moisture resistance in Australian conditions
• suits performance‑based moisture management strategies

This makes it especially valuable in remedial work, where installing a physical membrane is often impractical.

Can Damp Course Cream be used on solid brick, blockwork or stone?

Yes. The thixotropic formulation allows it to remain in contact with the mortar until fully absorbed, making it effective in:

• single, double and triple‑brick walls
• blockwork
• stone masonry
• heritage fabric with irregular substrates

It can be installed from one or both sides of the wall, depending on access.

Is Damp Course Cream suitable for DIY rising damp treatment?

Absolutely. One of the biggest advantages of Tech‑Dry Damp Course Cream is its DIY‑friendly application. It comes in 300 ml cartridges that fit a standard caulking gun—no pumps or pressure rigs required.

A typical installation involves:

1. Drilling a regular pattern of holes into the selected mortar course
2. Inserting the nozzle to the end of the drilled hole
3. Slowly filling each hole with cream

A single 300 ml tube treats around one lineal metre of single‑brick wall, involving two fills.

How long does Damp Course Cream take to work?

The treatment develops in stages:

• 0–24 hours: the cream absorbs into the mortar; a darkened band appears
• 1–7 days: the chemical reaction forms the new DPC
• Following weeks: moisture above the new DPC gradually evaporates

Full drying of walls depends on the presence of salts, ventilation and finishing materials.

Do I need special renders or coatings after treating rising damp?

For best long‑term results, pair the new DPC with:

• water-proofing renders tostop residual slats penetrating the new plaster finish
• breathable coatings
• compatible repair mortars

This prevents salt‑related damage and supports the drying process.

Why choose Tech‑Dry Damp Course Cream over traditional solvent‑based systems?

Tech‑Dry’s formulation is:

• water‑based and environmentally-friendly
• zero VOC and non‑hazardous under Worksafe Australia (when used as directed)
• over 80% active silane/siloxane for strong performance
• low‑odour and low‑mess
• designed specifically for Australian masonry

Tech‑Dry has been developing silicone‑based DPC systems locally since the early 1980s, with extensive testing on real Australian substrates.

How do I know if I need a new damp‑proof course?

Common signs of rising damp include:

• tide marks or damp patches at the base of walls
• blistering or peeling paint
• crumbling plaster
• salt efflorescence
• musty odours

If these symptoms appear consistently, reinstating a DPC in the the damp wall is often the most effective long‑term solution.