System Design Service
Basement & Tank Waterproofing System
Complete waterproofing solution for basements, underground structures, and water tanks using ULTRASEAL 427 system with DURABAND and DURASWELL for joint treatment. Suitable for both positive and negative side applications.
Application Types
Positive Side Waterproofing
Applied on the water-facing side (external side of basement wall)
Advantages:
- Direct protection against water pressure
- Easier access during construction
- Better for new construction
- Prevents water from reaching structure
Negative Side Waterproofing
Applied on the interior side (inside basement/tank)
Advantages:
- Suitable for existing structures
- No excavation required
- Can be applied from inside
- Effective for retrofitting
ULTRASEAL 427 can be applied on negative side with proper surface preparation
System Steps
1
Surface Preparation
Prepare the substrate for waterproofing application
Key Activities:
Clean surface thoroughly - remove all dirt, debris, and loose materials
Repair any cracks, holes, or damaged areas
Ensure surface is structurally sound
Remove any existing coatings or treatments that may interfere
Check for proper surface profile and texture
2
Joint Treatment with DURABAND / DURASWELL
Seal all joints, cracks, and movement joints
DURABAND
DURASWELL
Key Activities:
Identify all joints, cracks, and movement joints
Clean and prepare joint surfaces
Apply DURABAND waterproofing tape for static joints
Apply DURASWELL expansion joint sealant for movement joints
Ensure proper adhesion and coverage
Allow to cure before proceeding
3
ULTRASEAL 427 Application
Apply primary waterproofing membrane
Recommended Product: ULTRASEAL 427
Key Activities:
Mix ULTRASEAL 427 according to manufacturer specifications
Apply first coat evenly using brush, roller, or spray
Ensure complete coverage including all details
Allow first coat to cure (typically 4-6 hours)
Apply second coat perpendicular to first coat
Ensure proper thickness (typically 1.5-2mm per coat)
Pay special attention to corners, edges, and penetrations
4
Detail Treatment
Apply specialized treatment for corners, edges, and penetrations
Key Activities:
Reinforce corners with additional membrane layers
Treat all penetrations (pipes, conduits, etc.) with sealants
Apply edge treatments at terminations
Ensure all transitions are properly sealed
Verify complete coverage of all details
5
Quality Control & Protection
Verify system integrity and apply protection if needed
Key Activities:
Conduct visual inspection of entire application
Perform water test if applicable (for tanks)
Check for any pinholes or missed areas
Apply protective screed or coating if required
Document application for warranty purposes
Typical Substrates
Concrete (new and existing)
Cementitious renders
Blockwork (with proper preparation)
Brickwork (with proper preparation)
Existing waterproofing membranes (for repairs)
Typical Consumption
ULTRASEAL 427
1.5-2.0 kg/m²
Per coat, typically 2 coats required
DURABAND
As required
For joints and details
DURASWELL
As required
For expansion joints
Related Products
Waterproofing Systems
ULTRASEAL 427
Cementitious waterproofing membrane for basements and tanks
Waterproofing Accessories
DURABAND
Waterproofing tape for joints and details
Sealants
DURASWELL
Expansion joint sealant
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