The Big Question Every Project Team Asks
When waterproofing below-ground structures, one choice keeps coming up:
- Pre-applied membranes (installed before the pour)
- Post-applied membranes (installed after the concrete cures)
On paper, both protect structures. But in reality? The decision has huge implications for cost, programme, and long-term reliability.
Here’s a breakdown of how each approach impacts your bottom line.
Material Cost vs Hidden Cost
- Pre-applied systems (e.g. MAXIPRUFE PLUS, COMBI-SEAL): Higher upfront £/m². But often include built-in protection, reducing the need for primers or secondary treatments.
- Post-applied systems (e.g. HYDROPRUFE 3000/8000, liquids): Lower headline cost. But add in primers, multiple coats, surface prep… the "cheap option" isn’t always cheap.
Labour & Programme Impact
- Pre-applied: Needs careful sequencing with reinforcement + shuttering. But eliminates substrate prep entirely. Integrates naturally with pour sequence.
- Post-applied: Appears simpler, but requires surface cleaning, repairs, and prep. Adds more labour hours and extends programme duration.
Weather Dependency
- Pre-applied: Less exposed. Provides early-stage resilience and isn’t as weather-dependent.
- Post-applied: Highly sensitive to rain, moisture, or cold. Installation delays are common and may even require climate control.
Quality & Long-Term Risk
- Pre-applied: Bonds directly to fresh concrete, blocking lateral water migration. Reliable long-term.
- Post-applied: Depends heavily on substrate prep. Any imperfection = adhesion risk = potential failure.
When to Choose Each
- Pre-applied membranes → Best for new builds with clear sequencing, controlled conditions, and long-term performance focus.
- Post-applied membranes → Better for remedial works, irregular geometries, or phased builds with staggered access.
Whole-Life Cost Consideration
When weighing options, don’t stop at material price. Consider:
- Material + primers
- Labour hours
- Programme delays
- Rework + inspection risk
In many cases, pre-applied systems deliver better whole-life value, even with higher initial cost.
Protecting Complex Structures with Smarter Choices
Choosing between pre- and post-applied membranes isn’t just about today’s material price. It’s about whole-life project value: cost certainty, programme certainty, and long-term performance.
At Premcrete, we help contractors cut through the noise and pick the right system for their specific site conditions.
Need Expert Help Deciding?
Talk to our technical team today for site-specific guidance: technical@premcrete.com