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WATERPROOFING · APPLIED SYSTEM

Roof
WaterproofingMEMBRANE · WELD · SHED WATER

A membrane roofing system for large industrial and commercial roofs — torch-applied bituminous (APP) sheets or heavy liquid systems, lap-welded into one continuous skin that sheds heavy monsoon rain across factory sheds, warehouses and plant roofs.

LAP-WELDED MEMBRANE ROLLS INDUSTRIAL ROOF MEMBRANE SECTION REFERENCE DIAGRAM — TAP LAYERS BELOW
Lap-WeldedContinuous Skin
Large-AreaIndustrial Scale
Heavy-DutyMonsoon-Rated
TurnkeySurvey to Warranty
01
OVERVIEW

What is Roof Waterproofing?

Roof waterproofing here means the large-area membrane systems used to protect industrial and commercial roofs — factory sheds, warehouses, plant rooms and big institutional roofs — where the sheer scale and heavy monsoon load call for a different approach than a small terrace. The core is a robust membrane skin: torch-applied bituminous (APP) sheets rolled out and lap-welded edge to edge into one continuous covering, or a heavy liquid-applied system over large decks. Every overlap is heat-welded, every parapet, drain, vent and pipe penetration is sealed, and the roof is graded to shed water fast — giving wide-span roofs a single, seamless, monsoon-rated barrier that keeps production areas and stored goods dry below.

Torch-applied APP / liquid membrane Lap-welded continuous skin Large industrial & commercial roofs Monsoon-rated drainage
02
THE POLYZEN SYSTEM

How the System Is Built

A large roof is graded, then covered with a welded membrane skin sealed at every penetration. Tap any layer to see its role.

⟶ Tap a layer
05

Protective / Reflective Surface

UV & Heat Shield

A mineral-faced, reflective or protective top surface shields the membrane from UV and heat across a wide exposed roof, reducing thermal stress and extending service life. System values: Per TDS.

03
POLYZEN APPLIED SYSTEM

Engineered & Installed by POLYZEN

Roof waterproofing is delivered as a POLYZEN Applied System — surveyed, designed and installed turnkey by POLYZEN's trained applicators, with membrane type, detailing and surfacing specified to your roof's span, structure and exposure.

04
WHY IT WORKS

Built for Big Roofs & Heavy Rain

A large industrial roof has long water runs, dozens of penetrations and brutal sun and monsoon exposure. A welded membrane skin handles the scale — continuous, seamless and fixed down — while correct grading sheds water fast so it never sits and finds a way in. Performance is confirmed on the project specification.

Mechanism
Lap-welded membrane / heavy liquid skin
Scale
Large-span industrial & commercial roofs
Detailing
Sealed parapets, drains, vents & penetrations
POLYZEN Values
Per Project Specification

Membrane type, surfacing and detailing are specified per roof span, structure, slope and exposure. POLYZEN confirms finished values on the project specification and does not publish fabricated figures.

05
FROM SURVEY TO WATERTIGHT

The Application Process

01

Inspect & Assess

Survey the deck, slopes, drains and penetrations; identify ponding and the membrane system best suited.

02

Prepare & Grade

Strip failed coverings, repair the deck, correct falls to outlets, then prime the surface.

03

Membrane & Weld

Torch-apply and lap-weld the membrane, detail all penetrations and upstands, then surface it.

04

Test & Handover

Water / ponding test, final inspection of all seams and details, and written warranty.

06
TECHNICAL SUMMARY

System Specifications

PropertyDetail
System TypeRoof Waterproofing (Large Industrial / Commercial)
DeliveryPOLYZEN Applied System (turnkey)
Membrane TypeTorch-applied APP bituminous / heavy liquid
JointingHeat lap-welded continuous skin
DetailingParapets, drains, vents & penetrations sealed
Build-UpPrimer + Membrane + Detailing + Protective Surface
ScaleWide-span sheds, warehouses, plant roofs
Thickness / GradePer Project Specification
07
WHERE IT IS USED

Ideal Applications

Factories & Sheds
Warehouses & Logistics
Plant & Utility Roofs
Malls & Commercial
Institutional Blocks
RCC & Flat Roofs
08
09
ASSURANCE

Applied & Warranted

Every POLYZEN roof waterproofing system is installed by trained applicators and handed over after a water/ponding test, a seam-and-detail inspection and a written system warranty. Warranty terms are confirmed per project scope, roof structure and exposure.

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FAQ

Frequently Asked Questions

What is roof waterproofing?
It is the large-area membrane system used to protect industrial and commercial roofs — factory sheds, warehouses and plant rooms. Torch-applied bituminous (APP) sheets or a heavy liquid system are laid and lap-welded into one continuous skin, with every parapet, drain and penetration sealed and the roof graded to shed heavy rain.
How is roof waterproofing different from terrace waterproofing?
Terrace waterproofing usually uses a seamless liquid-applied membrane on smaller, walkable residential roofs. Roof waterproofing covers large industrial and commercial spans, where torch-applied lap-welded membrane sheets or heavy liquid systems and robust penetration detailing suit the scale and monsoon load. POLYZEN selects the right system for each roof during survey.
What is an APP / torch-applied membrane?
It is a polymer-modified bituminous membrane supplied in rolls. The underside is heated with a torch so it bonds to the primed deck, and adjacent rolls are overlapped and heat-welded so the seams fuse into one continuous waterproof skin — well suited to large, exposed industrial roofs.
Can an old leaking industrial roof be re-waterproofed?
Yes. Failed coverings are stripped, the deck is repaired, slopes and ponding corrected and penetrations re-detailed before a new membrane is applied. POLYZEN surveys the roof, identifies the leak and ponding points and recommends the most durable system rather than patching over old failures.
Is this a POLYZEN product?
Roof waterproofing is delivered as a POLYZEN Applied System — surveyed, designed and installed turnkey by POLYZEN. Membrane type, detailing and surfacing are specified to your roof span, structure and exposure during survey.
Does POLYZEN provide a warranty?
Yes. Every installation is water/ponding tested and handed over with a seam-and-detail inspection and a written system warranty, with terms confirmed per project scope, roof structure and exposure.
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Seal the Whole Roof. One Skin.

Get a roof survey, membrane recommendation and quote for your industrial or commercial roof.