DS Projects | Concrete & Masonry Leak Repair in Sydney
The Leak Came Back Because the Last Fix Didn't Reach It.
We Work Inside the Concrete. That’s Why Our Repairs Last.
25-Year Warranty. No Fine Print. No Exceptions.
Specialist concrete & masonry leak repair, not general waterproofing
Polyurethane & acrylic resin injection. Matched to your specific leak type
All work carried out by our in-house team never subcontracted
25-year warranty on materials and workmanship
Servicing residential, strata, commercial and infrastructure across NSW & ACT
Why Concrete Leaks Keep Coming Back?
Concrete looks solid. But it is not waterproof on its own.
Over time, cracks form. Construction joints open. Hydrostatic pressure builds behind walls — particularly in Sydney, where heavy rainfall and clay-heavy soils mean sustained water pressure against your structure long after the rain has stopped.
When water finds a path through concrete, it keeps using it. A repair that only addresses what is visible on the surface leaves the path intact. The water finds another way through, and the problem returns.
That is why the same leaks reappear in:
- Basements - Water through walls and floor joints after rain
- Balcony Slabs - Dripping into rooms below, pooling, staining
- Garages - Damp walls, efflorescence, persistent seepage
- Retaining walls - Weeping cracks, hydrostatic blowouts
- Lift pits - Active ingress under extreme pressure, equipment damage
- Block & brick walls - Rising damp, joint failure, internal moisture
The solution is not on the surface. It is inside the structure.
We Don't Cover Leaks. We Eliminate Them.
How does resin injection stop a concrete leak?
Most companies apply coatings or membranes to the outside of the problem. That approach has its place — but when water is already entering your structure under pressure, surface treatments cannot stop it. They buy time, temporarily, until the pressure wins again.
We specialise in concrete and masonry leak repair using polyurethane and acrylic resin injection — working from inside the structure, directly within the crack, joint or void where the water is travelling. The resin travels through the full depth of the leak path, bonds with the substrate, and forms a permanent seal from within.
Choosing the right injection resin
We use a comprehensive range of European-engineered injection resins. Choosing the right product for the specific conditions of each job is one of the most consequential decisions we make, and that process starts from your first contact with us and carries through to the day we finish on site.
Our range covers the full spectrum of injection technology:
Single-part open-cell hydrophilic resins
React aggressively with water and expand to fill the void. Used where water is actively flowing and an immediate, high-swelling seal is needed.
Single-part closed-cell resins
Deliver a controlled expansion profile — selected where a more precise, contained seal is required within the crack or void structure.
Two-part non-swelling hydrophobic resins
Produce a rigid, moisture-resistant seal engineered to last in excess of 120 years. Specified where long-term structural integrity is the primary requirement.
We do not accept a one-product-fits-all approach. The substrate type, the nature of the crack or joint, whether water is actively flowing, the degree of structural movement, the age and condition of the concrete — all of it matters, and all of it is factored into the method before a single port is drilled.
A Full System — Inside Out
Injection is central to what we do, but it is one part of a broader system. Once the ingress point is sealed, we apply crystalline self-healing systems along with cement and acrylic-based hydrostatic systems to the surrounding substrate. This builds a layered zone of protection around the treated area rather than a single point seal.
Most structures deal with thermal cycling — the ongoing expansion and contraction of materials as temperatures rise and fall. Left untreated, the surrounding substrate can open new pathways over time. Our system addresses this by working from the inside out, with the correct layering applied over the substrate face for durable, whole-area protection.
On completion, treated areas are left clean and fully prepared for final finishes — tiles, render, Gyprock, painting — ready for your finisher to work directly on.
How It Works On Site
Inspection & Diagnosis
We attend the property and carry out a thorough inspection — tracing the water path through the structure to identify the actual source of ingress where possible, not just the visible damp patch. Substrate conditions are assessed and the correct product and method determined before work begins.
Product Selection & Injection
The appropriate resin — or combination of resins — is selected from our European range and injected under controlled pressure directly into the crack, joint or void. The material travels through the full depth of the leak path, bonds with the substrate and creates a permanent seal from within. Active water flow is not an obstacle — the resins are designed to work in exactly those conditions.
System Layering & Substrate Preparation
With the ingress point sealed, crystalline self-healing and hydrostatic protection systems are applied to the surrounding substrate in the correct sequence, building complete layered protection across the treated area. Everything is then cleaned down and left ready for finishing.
Testing & Warranty
The repaired areas are tested on completion and your 25-year warranty issued in writing — covering materials, workmanship and the actual problem: water ingress through concrete and masonry. No fine print.
“We were getting calls every week from homeowners across Parramatta, Ryde, Strathfield, the Inner West, the East, the North and all across NSW — same story every time. A patch had been applied, it had held for a season, and now the leak was back. Often worse.
Selecting the right injection material for the specific leak conditions is what separates a permanent repair from a temporary one. That’s the decision we make on every single job.”
Eoin Daniels, Quality & Development Manager, DS Projects
Our Services
Every service we offer addresses a specific type of water ingress — same standard, same in-house team, same 25-year warranty across all of them.
Basement Leak Repair
Leaking basement walls and floor joints are among the most common and most damaging water ingress problems in Sydney homes and strata buildings. We inject directly into the crack or joint, sealing the leak inside the concrete — no excavation, no demolition required in the vast majority of cases.
Balcony Leak Repair
Water penetrating through balcony slabs into rooms below is a serious and often costly problem in multi-storey residential and strata properties. We identify the failure point — cracked slab, failed joint or compromised membrane edge — and repair from within.
Concrete Crack Repair
Active cracks in concrete walls, slabs and columns allow water to travel under pressure through the full depth of the structure. Resin injection seals the crack through its full width using the product best suited to that crack's specific conditions, followed by protective hydrostatic layering over the substrate face.
Basement Dampness Repair
Persistent basement dampness is frequently driven by capillary action and osmotic pressure rather than a visible crack. We identify the source and apply the appropriate combination — injection, crystalline self-healing systems, hydrostatic coating or all three — to eliminate the moisture permanently and protect the full substrate area.
Block & Brick Leak Repair
Masonry walls absorb and transmit water differently to poured concrete. We use DPC injection and crystalline self-healing systems designed specifically for block and brick construction to stop rising damp and lateral water ingress at the source, with protective layering applied to the treated face.
Lift Pit Leak Repair
Lift pits sit at the lowest point of any building, making them one of the most demanding water ingress environments we work in. Their depth places them under extreme hydrostatic pressure — in many Sydney buildings, groundwater pressure at pit level can reach and exceed 100 kPa after heavy rainfall, particularly where water tables are high or soils are clay-heavy
We treat lift pits with a multi-step, multi-layer system built specifically for this environment. Injection sealing eliminates active ingress first, followed by crystalline self-healing and hydrostatic systems applied in the correct sequence across the full substrate. The outcome is a completely sealed pit that protects lift mechanics and electrical equipment from the moisture damage that causes costly failures and compliance issues.
With over 50 lift pits completed across NSW and the ACT, this is work we know in depth and take seriously every time.
Working With DS Projects
Bringing in a contractor for a problem that someone else already tried and failed to fix takes trust. This is what our process looks like.
We Respond the Same Day
From the moment you contact us — phone, email or enquiry form — you will hear back the same day, usually within hours. Once you have provided your scope or we have completed our inspection, a written proposal is with you within 24 hours and more often than not within 8.
Inspection & Diagnosis
We attend the property and carry out a thorough inspection. We aim to trace the water path through the structure to identify the actual source of ingress where possible — not just the damp patch on the wall. This is the step most companies skip, and it is the reason most repairs fail.
Fixed-Price Proposal
A written, lump-sum proposal with no ambiguity and no hidden costs. You know exactly what will be done, how long it will take and what it will cost before anything starts.
In-House Installation
Every job is carried out by our own team — never subcontracted. The people who assessed your property are the people who show up to do the work.
Testing, Completion & Handover
Repaired areas are tested, protective system layering applied, and all surfaces left clean and ready for final finishes. Your 25-year warranty is issued in writing on the day we complete.
Across NSW & ACT
We service all of New South Wales and the ACT, with regular work across Greater Sydney — the CBD, North Sydney, Eastern Suburbs, Inner West, Lower and Upper North Shore, Western Sydney, the Hills District, Southern Sydney and the Sutherland Shire.
Our teams work across both metropolitan and regional NSW and are experienced in the varied soil conditions, water table depths and structural environments found across the state.
Outside these areas — get in touch. If we can reach you, we will be there.
- Office: Suite 2, 109 Victoria Road, Drummoyne NSW
- Phone: 1800 727 531
- Web: dspr.com.au
What Our Clients Say
Still Getting Water After Every Storm?
If a previous repair didn’t hold — or you want it done properly the first time — call us.
Concrete and masonry leak repair using polyurethane and acrylic resin injection is a permanent solution. Not a seasonal one.
DS Projects. Certainty in every repair.
All of NSW & ACT · 25-Year Warranty · In-house team · No subcontracting