PU Grouting & Crack Injection in Singapore
Polyurethane grouting injects a resin directly into a crack, where it reacts with moisture and expands to form a watertight seal from inside the concrete. It is the go-to method for sealing active leaks with minimal disruption.
Signs you need this
- Active seepage through a visible concrete crack
- Inter-floor leakage tracking through the slab
- Water weeping along a construction joint
- Damp basement or planter walls
- Leaks that return after surface-only repairs
How we fix it properly
We drill injection ports along the crack at calculated intervals, then pump PU resin under pressure until it travels through the full depth of the crack. On contact with moisture it foams and cures into a flexible, watertight seal.
Because the work is targeted to the crack, there is little hacking and the surrounding finishes are largely untouched — ideal for occupied homes and operating buildings.
PU injection is often combined with a surface membrane for belt-and-braces protection; we advise when that extra step is worthwhile and when injection alone is sufficient.
Common causes we look for
- Shrinkage and settlement cracks in concrete
- Cold joints between concrete pours
- Hairline cracks opened by structural movement
- Failed surface treatments over a live crack
Our pu grouting process
- 1
Crack mapping
Identify the crack path and set out injection ports.
- 2
Port installation
Drill and fix packers along the crack.
- 3
Injection
Pump PU resin under pressure to fill the full depth.
- 4
Curing
Resin foams and cures into a flexible watertight seal.
- 5
Finishing
Remove ports and make good the surface.
PU Grouting FAQs
Still unsure? A free assessment answers everything specific to your property.
Get a free, honest assessment
Tell us what you’re seeing — we’ll take it from there.
Is PU grouting a permanent fix?
For a stable crack, PU injection forms a durable, flexible seal that lasts. If the crack is caused by ongoing structural movement, we will say so and recommend addressing the movement as well.
Will PU grouting damage my floor or walls?
Minimal. The work is confined to small injection ports along the crack, so the surrounding tiles and finishes generally stay intact. This is why it suits occupied homes.
Related services
All servicesCeiling Leak Repair
Brown stains and dripping ceilings traced to source and sealed — not just repainted to come back next month.
Basement & Car Park Waterproofing
Below-ground structures sealed against hydrostatic water pressure to keep basements, lift pits and car parks dry.
Water Leak Detection & Repair
Pinpoint hidden leaks with non-destructive tools before we lift a single tile — find the source, fix it once.
Need pu grouting help today?
Book a free, no-obligation assessment or call our 24/7 line. Honest diagnosis, no unnecessary hacking.