Quotation decision guide
Roof Waterproofing Cost and Scope Guide for Hong Kong
A roof waterproofing quotation cannot be reduced to a fixed rate multiplied by area. The existing membrane, substrate, drainage, details, access and operational constraints must first be translated into a defined scope.
Short answer
A seamless Polyurea overlay may be assessed where the existing substrate and membrane can be retained. Complete removal and reconstruction is commonly assessed where failure is widespread, the substrate is unsound or drainage falls must be rebuilt. The final selection and quotation for either approach require a site inspection.
Editorial record
Published2026-07-27
Updated2026-07-28
Content ownerProficient Waterproofing & Engineering Ltd.
Reviewed byProficient Waterproofing technical team
The scope and public service statements are drawn from existing cases, the legacy main-site service page and the inspection workflow. Final prices, tests and warranty terms are subject to the project quotation and contract.
Scope comparison
Two approaches answer different site conditions.
- 01
Seamless Polyurea overlay
Suitable when
An existing substrate and membrane that can be retained, with ageing, local cracking or a need for a continuous seamless finish.
Scope to confirm
- — Inspect and prepare the existing surface
- — Reinforce outlets, wall junctions and penetrations
- — Apply the continuous waterproofing layer and specified finish
Watch for
Moisture, hollow areas, weak substrate or failed drainage still require proper rectification.
- 02
Complete removal and reconstruction
Suitable when
Widespread membrane failure, substrate repairs, inadequate drainage falls or an existing build-up that cannot be reliably retained.
Scope to confirm
- — Remove the specified existing layers
- — Repair and level the substrate and drainage details
- — Rebuild the waterproofing, protection and agreed finishes
Watch for
Demolition, waste handling, access, noise, weather and reinstatement requirements directly affect the programme and quotation.
Cost drivers
Eight information groups that change the scope
A quotation should state what is included and excluded. Roofs of the same area can require very different work because of their substrate, access, drainage and reinstatement conditions.
- 01Measured work area and actual zones
- 02Access, material handling, hoisting, scaffolding and work-hour limits
- 03Removal, waste handling and protection
- 04Cracks, hollow areas, moisture or weak-substrate repairs
- 05Outlets, parapets, equipment bases, pipework and penetrations
- 06Water testing, inspections and photographic records
- 07Tiles, protection, equipment and other reinstatement
- 08Warranty scope, limitations and handover documents
Why inspection matters
A fixed unit rate cannot replace a site inspection
Photographs support an initial assessment but do not fully reveal membrane adhesion, substrate moisture, hollow areas, concealed junctions or drainage falls. Before a formal quotation, the visible issues must be converted into a measurable scope.
The quotation should identify assumptions, main work stages, detail treatment, testing or records, reinstatement and exclusions so owners, Owners’ Corporations and property managers can compare on a like-for-like basis.
Enquiry checklist
Prepare these photographs and details for an initial assessment
You do not need to select a material before making an enquiry. Start with a clear record of the existing condition so the engineering team can identify what remains unknown.
- 01Full-roof views and the likely work zones
- 02Leakage, staining, cracking or ponding locations
- 03Close-ups of outlets, parapets, wall junctions, equipment bases and pipework
- 04Approximate area, building type and available access
- 05Known waterproofing system, repair year or work records
- 06Operational limits, preferred timing and document requirements
Free quotation
Free initial assessment
Want an initial roof waterproofing quotation?
Send roof overview photos, leakage locations and the approximate area through WhatsApp. We will provide a free initial assessment and arrange a quotation according to the site conditions.
No need to select a waterproofing system first.
Project evidence
Related project records
Kwai Chung
On Yam Shopping Centre, Kwai Chung
Estate-podium and roof waterproofing
Hong Kong
Private Clubhouse, Sai Kung District
Large-area roof waterproofing for an institutional building
Hong Kong
Wadee Garden Blocks 21 and 22
Residential-estate roof waterproofing
Silverstrand
Silver Terrace Road, Silverstrand
Coastal detached-house waterproofing
North District
Kwu Tung
Plant-room roof waterproofing
Lantau Island
No. 38 South Lantau Road
Low-density residential waterproofing
Tai Tam
Redhill Peninsula No. 166
Roof waterproofing and detail treatment
FAQ
Questions to settle before the works
Can photographs provide a formal quotation?+
Photographs normally support only an initial assessment. The work area, substrate, access, drainage, details and reinstatement must still be confirmed; complex or larger projects generally require a site inspection.
Is an overlay always cheaper than complete reconstruction?+
Not necessarily. Extensive substrate repairs, complex details or an existing membrane that cannot be reliably retained will change the scope and cost.
Should testing and construction records be included?+
The quotation should state the agreed testing, inspections, progress photographs and handover documents. Not every site is suitable for the same test, so this cannot be promised before inspection.
How should two roof-waterproofing quotations be compared?+
Compare substrate preparation, details, drainage, the main membrane, protection and reinstatement, testing records, warranty conditions and exclusions before comparing the total price.
Source record
Sources and verification links
- 01Proficient Waterproofing: services and pricing reference
Legacy-site scope for roof overlays, complete removal, testing, photographic reports and warranties.
- 02Proficient Waterproofing: professional credentials
Public company, CIC, ISO, RMWCs(CO) and material-applicator information.
- 03Hong Kong Q-Mark Service Scheme licensee list
Independent confirmation of the company name and waterproofing-service certification scope.