Damp-Proofing

1. Rising Damp

• Ground moisture travels up through walls
• Tide marks and salt deposits at low level
• Failed or missing damp-proof course

2. Penetrating Damp

• Water enters through walls, roof or windows
• Often linked to failed pointing or flashing
• Patches grow during wet weather

3. Condensation Damp

• Warm moist air meets cold surfaces
• Black mould around windows and corners
• Worst in bathrooms, kitchens and bedrooms

minor Repairs

• Repoint failed mortar joints
• Reseal around windows, doors and abutments
• Improve ventilation with extractors and trickle vents

moderate Repairs

• Inject chemical damp-proof course
• Replace damaged plaster with salt-resistant render
• Install positive input ventilation (PIV)

major Repairs

• Internal tanking with cementitious or membrane systems
• External waterproofing and drainage to basement walls
• Full strip-out and rebuild of severely affected areas

When Replacement Is Needed

• Visible tide marks on lower walls
• Persistent mould despite ventilation
• Converting cellars or basements to habitable space

Installation Steps

1. 1

   Diagnose

   • Identify the type of damp with moisture meter
   • Locate the source, not just the symptom
2. 2

   Repair Source

   • Fix gutters, pointing, flashing or leaks
   • Improve ground levels and drainage
3. 3

   Damp-Proofing System

   • DPC injection, tanking or cavity drain membrane
   • Match system to building type
4. 4

   Replaster

   • Use salt-resistant render and undercoats
   • Allow drying time before finishing
5. 5

   Decorate

   • Use breathable paints where appropriate
   • Avoid trapping moisture in walls