Training · First course
Substrate Preparation & Moisture Testing
Most flooring, coating and waterproofing failures start with the slab, not the product. This course teaches the site judgement that decides whether a substrate is ready, and how to record that you checked.
6 modules20–30 minutes eachCertificate of completion
- Free preview below
Why substrate failure happens
Moisture, contamination and weak substrates cause most flooring and waterproofing failures, not the product. Learn the three failure types and why the client will blame you, not the slab.
- Drafted
Visual & physical assessment
Tap testing, laitance, cracking, contamination, falls and slab history. Plus the photo habit that protects you in a dispute.
- Drafted
Moisture testing methods
Surface meters, in-situ RH probes and calcium chloride tests. What each one tells you, and which one the data sheet actually asks for.
- In production
Matching preparation to the system
Grinding, shot blasting and scarifying. Surface profile, crack and joint treatment, and priming.
- In production
Documentation & client sign-off
A simple assessment record, written sign-off, and how it links to your quote exclusions.
- In production
Common mistakes & case studies
Real failures from site: undetected moisture, delaminating screeds and rushed testing, and what each one cost.
Free preview · Module 1
Why substrate failure happens
Most flooring and waterproofing failures are not product failures. They are substrate failures the product could never overcome. Three causes account for almost everything you'll see on site.
Moisture. Slabs, especially new ones or slabs without a damp-proof membrane, can hold moisture well below the surface long after they look dry. A coating or adhesive traps that moisture, and vapour pressure eventually pushes the system off. You see it as blistering, delamination or a soft coating weeks or months later.
Contamination. Oil, grease, curing compounds, laitance, old sealers, dust and release agents all sit between your system and sound concrete. A strong bond to contamination is still a bond to contamination.
Weak or unsound substrate. Friable, cracked, poorly compacted or moving substrates fail whatever you do to the surface, because the problem is underneath it.
The client rarely blames the substrate. They blame the installer or the product. That is why assessment and documentation matter as much as the technical steps. If a substrate can't support the system, the remedial work is a separate, billable scope, not something you absorb into your price.