Tips & Solutions
How to Choose a Waterproofing Contractor in the Philippines
“Which contractor can properly understand the problem, recommend an appropriate system, and execute the details required to keep water out?”
When a building develops a leak, the immediate reaction is often to find someone who can waterproof the affected area as quickly as possible.
For commercial and industrial properties, however, choosing a PCAB-licensed waterproofing contractor should involve more than comparing prices or selecting a familiar waterproofing product.
A leak may appear simple from the interior, but water can enter the building from another location, travel through construction joints or concealed spaces, and only become visible several meters away.
The more important question is therefore not:
“Which contractor can apply waterproofing?”
It is:
“Which contractor can properly understand the problem, recommend an appropriate system, and execute the details required to keep water out?”
Here are the key factors engineers, property managers, facilities teams, and procurement professionals should consider.
1. Start With the Problem, Not the Product
A contractor should not recommend a waterproofing system before understanding the existing condition.
An initial assessment should consider factors such as:
Location and pattern of leakage
Existing waterproofing system
Condition of the substrate
Cracks and construction joints
Drainage and roof slope
Pipe and equipment penetrations
Parapets and wall interfaces
Waterproofing terminations
Previous repairs
Possible movement of the structure
Areas outside the obvious leak location
Waterproofing is part of the broader building envelope. Roofs, walls, joints, penetrations, flashings, drainage systems, and other exterior components must work together to prevent water intrusion.
A technically sound recommendation therefore begins with identifying the probable source and mechanism of leakage—not immediately prescribing a coating or membrane.
2. Examine the Details
Large waterproofed surfaces often receive most of the attention.
In practice, the more difficult areas are frequently much smaller:
Corners
Drains
Pipe penetrations
Equipment supports
Parapet terminations
Expansion joints
Concrete-to-metal interfaces
Door thresholds
Flashings
Changes in elevation
Transitions between different waterproofing materials
These locations deserve particular attention during inspection, specification, and installation.
Waterproofing literature refers to the 90%/1% principle: a large proportion of water intrusion problems can originate from a very small portion of the building envelope, particularly at transitions and terminations.
For this reason, a proposal that specifies only the waterproofing material but provides little information about detailing may be incomplete.
Ask:
How will the contractor treat the difficult parts of the building?
3. Make Sure the Proposed System Fits the Application
There is no single waterproofing material that is appropriate for every condition.
Common systems include:
TPO and other sheet membranes
Polyurethane liquid-applied waterproofing
Cementitious waterproofing
Acrylic coatings
Modified bitumen membranes
Crystalline waterproofing
Injection systems
Joint sealants
The correct choice depends on the actual service conditions.
For example, the contractor may need to consider:
Interior or exterior application
Horizontal or vertical surface
UV exposure
Expected structural movement
Hydrostatic pressure
Existing substrate
Accessibility
Traffic or mechanical exposure
Required downtime
Compatibility with existing materials
Drainage conditions
A responsible waterproofing contractor should be able to explain why a particular system is being recommended and where its limitations are.
Be cautious when the same product is proposed for nearly every type of waterproofing problem.
4. Compare Scope and Experience, Not Just Price
Two quotations may appear similar while covering very different scopes.
Before comparing prices, check:
Surface preparation
Repairs
Waterproofing system
Application thickness or number of coats
Detailing
Testing
Access and safety requirements
Warranty
Also request relevant project experience.
A contractor experienced in commercial roof decks, high-rise façades, industrial facilities, or large membrane installations may offer a very different level of capability from one primarily handling small residential repairs.
The better comparison is:
scope vs. scope, system vs. system, and risk vs. risk.
5. Evaluate Documentation, Warranty, and After-Sales Support
Commercial waterproofing projects often involve engineering, procurement, property management, and management approval.
A professional contractor should be able to provide appropriate documentation such as:
Formal proposal and scope of work
Technical data sheets
Method statement
Work schedule
Progress and completion records
Warranty documentation
The warranty should also clearly state what is covered, excluded, and required from the property owner after completion.
A long warranty is less useful than a clear and technically defensible one.
Choosing the Right Waterproofing Contractor
Waterproofing is not simply the application of a coating or membrane.
Successful waterproofing depends on the correct diagnosis, appropriate system selection, proper detailing, substrate preparation, workmanship, and maintenance.
For commercial and industrial properties, the right contractor should be able to understand the problem, explain the recommendation, execute the work properly, and support it with professional documentation.
Need a Waterproofing Assessment?
EVERDRY provides waterproofing inspection, technical assessment, system recommendation, and installation for commercial, industrial, institutional, and professionally managed properties.
