PVC Roofing: Know Everything Before Installing

Written By Adam Paul - Waterproofing Expert

PVC roofing is a single-ply thermoplastic roofing system made from Polyvinyl Chloride. It consists of two layers: the top is UV-resistant ply, and the bottom ply is loaded with plasticizers for flexibility. PVC roofing is a heat-welded roofing membrane at the seams. PVC roofing is mainly of three types such as Standard PVC Membrane, PVC KEE Membrane, and Fleece-Backed PVC Membrane. PVC roofings consist of important properties such as exceptional waterproofing capability, flexibility, can last 25-35 years, excellent UV resistance, super chemical resistance, excellent heat resistance, and seam strength.

PVC roofings have both pros and cons. But they are used as roofing due to higher water-tight integrity, energy efficiency, low maintenance, adaptability, and sustainability. PVC roofing is highly recommended in hot, sunny, humid, and chemically exposed environments due to its reflective surface and chemical resistance.

PVC roofing systems can be installed mainly in 3 methods, such as mechanically attached, fully adhered, and ballasted methods, on the building’s structure. We highly recommend that you hire an expert to install PVC roofing to minimize the laying problems. In order to enhance the durability of PVC roofing, it should be inspected properly, cleaned the surface regularly, limit the foot traffic, keep drains and gutters clean, trim nearby trees, and use compatible materials for repairs and maintenance. If you do not address the possible problems on time, PVC roofing can be damaged.

So As waterproofing experts, we highly recommend you to inspect and address the PVC roofing problems on time to minimize possible problems and erros.

What Is PVC Roofing?

PVC roofing is a single-ply thermoplastic roofing system made from Polyvinyl Chloride, a durable synthetic plastic. PVC roofing system consists of two layers of PVC: a top UV-resistant ply and a bottom ply often loaded with plasticizers for flexibility. 

These two PVC layers have sandwiched in between is a polyester scrim for added tensile strength and dimensional stability. PVC roofing is a heat-welded roofing membrane at the seams. It forms a continuous monolithic barrier that prevents leaks and withstands chemical exposure, fire, and heavy foot traffic on the roof.

Read More: What You Should Know About PVC Waterproofing?

What Are Two Types Of PVC Roofing?

PVC roofing comes in three types such as Standard PVC Membrane, PVC KEE Membrane, and Fleece-Backed PVC Membrane. Each has specific applications and benefits, depending on the building design, environment, and performance expectations.

Standard PVC Membrane: This is the most commonly used PVC roofing type. It has excellent UV resistance and reflects up to 90% of sunlight. Membranes like Versico’s 60-mil polyester-reinforced PVC offer a service life exceeding 30 years. We recommend this for office complexes and warehouses with moderate foot traffic areas.

PVC KEE Membrane: Infused with Ketone Ethylene Ester, KEE-enhanced PVC roofing has higher molecular weight and retains flexibility over decades. KEE (e.g., Elvaloy®-based) resists plasticizer migration, which prevents embrittlement and shrinkage. We used this on a coastal food-processing plant where chemical exposure and high winds demanded superior durability.

Fleece-Backed PVC Membrane: This type features a polyester fleece underside, boosting puncture resistance and improving adhesion on irregular substrates. With added wind uplift resistance, it’s ideal for re-roofing over existing assemblies. We’ve installed this on airport terminals where membrane movement needed to be minimized under thermal expansion.

Read More: What You Should Know About Roof Waterproofing?

What Are The Properties of PVC Roofing?

These are the key properties of PVC roofing

1. PVC roofing has an exceptional waterproofing capability
2. PVC roofing has exceptional flexibility
3. PVC roofing system can last 25 to 35 years if maintained properly
4. PVC roofing offers industry-leading UV resistance
5. PVC roofing provides superior chemical resistance
6. PVC roofing has excellent heat resistance
7. PVC roofing offers industry-leading seam strength

Water Resistance Of PVC Roofing

PVC roofing is engineered to provide exceptional waterproofing capability, making it one of the most leak-resistant systems we install at Aqviz. The membrane’s heat-welded seams create a continuous, monolithic surface, eliminating the risk of adhesive breakdown or seam separation, which is common in EPDM or asphaltic systems.

PVC roofing maintains seam integrity with welds that penetrate up to 1,100°F (593°C), unlike TPO, which may require seam taping or re-welding due to expansion cycles. We observed that PVC roofs outlast bitumen, shingles, and rubber membranes by resisting ponding water, capillary action, and freeze-thaw splitting. Hence, PVC roofing is ideal for buildings with complex drainage or HVAC units on the roof, where pooling is a constant concern.

Flexibility Of PVC Roofing

PVC roofing membranes are engineered for exceptional flexibility, even in extreme weather conditions. PVC’s flexibility makes detailing around vents, skylights, and curbs smoother and safer. For example, on a rooftop with dozens of mechanical penetrations, PVC roofing allowed our crew to complete flashing with fewer seams and lower leak risk.

Durability Of PVC Roofing

A properly installed and maintained PVC roofing system can last 25 to 35 years, depending on membrane thickness, exposure, and installation quality. Premium-grade PVC systems like KEE-modified membranes (e.g., Elvaloy®-based) can extend lifespan to 40+ years, especially in chemically exposed or high-UV environments. PVC consistently outperforms when longevity is a top priority for the building envelope, compared to TPO (20-25 years) or EPDM (20-30 years).

UV Resistance Of PVC Roofing

PVC roofing offers industry-leading UV resistance, a critical feature for roofs in high-sun exposure areas. Many white PVC membranes achieve Solar Reflectance Index (SRI) ratings of 108. It means PVC roofing reflects more solar energy and absorbs less heat. This reduces thermal stress and cooling loads, particularly on large commercial buildings. PVC holds its color and elasticity longer when compared to EPDM (which is black and absorbs heat) and TPO (which can degrade under prolonged UV unless properly stabilized). 

Chemical Resistance Of PVC Roofing

PVC roofing provides superior chemical resistance, making it the go-to membrane for facilities exposed to oils, fats, solvents, or industrial discharge. PVC roofing remains chemically stable, unlike TPO membranes, which can degrade or discolor when exposed to fats or fuels. For example, in ASTM D543 immersion testing, PVC showed minimal mass change after 7 days in Jet Fuel A or animal fats, whereas TPO and EPDM exhibited visible swelling or surface distortion. Hence you can install PVC over TPO for rooftops near commercial kitchens or petrochemical environments.

Fire And Heat Resistance Of PVC Roofing

PVC roofing excels in fire and heat resistance, offering Class A fire ratings in most assemblies and being inherently self-extinguishing. Hence PVC systems can be used on schools, hospitals, and commercial buildings where fire safety codes are stringent. Its flame spread rating under ASTM E108 confirms its ability to prevent fire propagation, even when exposed to a direct ignition source.

Seam Strength Of PVC Roofing

PVC roofing offers industry-leading seam strength, thanks to its heat-welded seams that thermoplastically bond one sheet to another. In ASTM D1876 peel tests, PVC seam strength often exceeds 25 lbf/in PVC roofing seams are fused at temperatures over 1,100°F (593°C). The heat weladable rate of the PVC roof seam is 8’-10’ per minute. It helps to create single continuous membrane that’s often stronger than the field sheet itself. 

PVC roofing offers greater consistency and lower failure rates compared to EPDM, which relies on adhesives or tape seams, and TPO, which requires very precise welding conditions. We always recommend PVC for long-term seam integrity on complex roofs with multiple penetrations.

What are the 5 Benefits of PVC Roofing?

These are the 5 benefits of PVC roofing

1. Heat-welded seams: PVC roofing seams are hot-air welded. It creates watertight joints stronger than glued or taped seams found in EPDM and TPO.
2. Superior chemical resistance: PVC withstands oils, greases, and acidic contaminants, unlike TPO or asphalt-based systems.
3. UV and heat reflectivity: White PVC membranes have an SRI rating up to 108, reducing roof temperatures and HVAC loads better than dark EPDM.
4. Fire resistance: PVC roofing is self-extinguishing and meets UL Class A standards, unlike EPDM which may continue to burn when ignited.
5. Proven longevity: With over 50 years of field performance, PVC roofing offers unmatched track records for durability and return on investment.

What Are The Disadvantages Of PVC Roofing?

While PVC roofing performs exceptionally well, it does have a few limitations to consider based on project type and environment. At Aqviz, we always help clients weigh these drawbacks during system selection.

1. Higher initial cost: PVC roofing systems typically cost more than EPDM or modified bitumen, especially with thicker membranes or fleece backing.
2. Brittleness in cold installation: PVC roofing sheets can crack if unrolled or handled improperly below -5°C (23°F) although flexible after installation.
3. Incompatibility with TPO: PVC and TPO are chemically incompatible, so transitioning between the two systems requires careful detailing.
4. Membrane shrinkage: Poor-quality or unreinforced PVC roofing can shrink over time. It can cause stress, flashings and cause seams pull if not reinforced properly.
5. Plasticizer migration: Standard PVC (non-KEE) roofing may lose flexibility over time as plasticizers migrate, leading to cracking or chalking without regular maintenance.

Read More About: EPDM Roofing: Know Everything Before Installing

Why PVC Roofing Is Good For Roof?

PVC roofing is good for roof due to these 5 reasons such as,

1. Higher watertight integrity: Heat-welded PVC roofing seams form a monolithic surface that prevents leaks better than glued seams found in EPDM or TPO systems.
2. Energy efficiency: High reflectivity of PVC roofing reduces rooftop temperatures by up to 40%, cutting cooling costs in sun-exposed areas.
3. Requires low maintenance: Unlike asphalt roofs, PVC roofing systems resist algae, grease, and UV damage, minimizing upkeep over the years.
4. Adaptable to complex roofs: PVC roofing membranes are highly flexible. Hence they are ideal for detailed work around HVAC, vents, and rooftop units.
5. Sustainability roofing option: PVC roofing can be recycled up to 7 times without losing strength, making it a smart choice for eco-conscious buildings aiming for LEED credits.

In Which Climate Is PVC Roofing Recommended?

PVC roofing is highly recommended in hot, sunny, humid, and chemically exposed environments due to its reflective surface and chemical resistance. At Aqviz, we frequently install PVC membranes in southern U.S. states like Florida, Texas, and California, where solar radiation and heavy rainfall demand durable, energy-efficient roofing.

Its high solar reflectivity (SRI up to 108) makes it ideal for regions with intense heat, significantly reducing rooftop temperatures and cooling loads. Additionally, the flexibility of PVC roofing allows installation in colder regions like the Midwest and Northeast, especially when fleece-backed or adhered systems are used. This adaptability makes it a truly all-climate membrane for low-slope roofs.

What Are The Installation Methods Of PVC Roofing?

PVC roofing systems can be installed mainly in 3 methods such as mechanically attached, fully adhered, and ballasted methods, on the building’s structure. Each method impacts cost, performance, and wind uplift resistance.

Mechanically attached systems: This method secures the PVC roofing membrane using plates and fasteners along the seams. Heat welding creates watertight overlaps over the fasteners. Mechanically attached PVC roofing is a faster and more cost-effective installation. It is Ideal for large, open commercial roofs and buildings with structural decks like steel or wood.

Fully Adhered Systems: The PVC roofing membrane is bonded directly to the substrate with adhesives over insulation or cover boards. Fully adhered PVC roofing offers strong wind uplift resistance and smooth aesthetics. Fully adhered PVC roofing is suited for irregular-shaped roofs or high-wind coastal regions where full adhesion reduces membrane flutter.

Ballasted Systems: Ballasted PVC roofing membranes are loose-laid over the deck and held down by stone or paver ballast. A ballasted PVC roofing system provides thermal mass and excellent UV shielding. Ballasted PVC roofing systems are recommended for flat roofs in snowy or high-sun zones where added weight helps resist wind uplift and improves energy efficiency.

How To Install PVC Roofing?

At Aqviz, we follow a precise 6-step process to ensure every PVC roofing system delivers maximum waterproofing, durability, and seam integrity. 

1. Roof deck preparation: Clean and inspect the roof surface to ensure it’s dry, smooth, and structurally sound. Any damaged decking or insulation must be replaced.
2. Install insulation: Apply polyiso or EPS insulation boards on the roof. Attach them using mechanical fasteners or adhesive. But it depends on the roofing system.
3. Lay out the PVC membrane: Unroll the PVC roofing sheets across the roof, aligning them properly with minimal overlaps to reduce waste.
4. Secure the membrane: Attach the PVC roofing sheets mechanically, fully adhere with bonding adhesive, or loose-lay if using a ballasted system.
5. Heat-Weld the seams: Weld overlapping the PVC roofing sheets using a hot-air welder at approximately 1,100°F (593°C) to ensure watertight seams.
6. Seal flashings and penetrations: Flash all roof corners, pipes, curbs, and edges with preformed PVC roofing accessories or custom-welded patches on the roof.
   

Can You Install PVC Roofing DIY?

No, you can’t install PVC roofing DIY because PVC  roofing requires specialized equipment like hot-air welders, rollers, and seam probes. So you have to spend a lot of money on this equipment for a single use.

As well as certified installers, follow manufacturer specifications (e.g., Carlisle, Firestone, Sika) and local building codes that you can’t find and learn quickly. So we highly recommend that you hire an expert for the PVC roofing. It helps to prevent poor seam welds, insufficient fastening, or improper flashing, all of which can cause premature leaks.

How to Enhance PVC Roofing?

Protecting your PVC roofing system is essential to ensure its full service life and to prevent avoidable issues like seam failure or membrane puncture. At Aqviz, we apply these six practical methods to help our clients get the most from their PVC roof investment.

1. Schedule Bi-Annual inspections: Inspect the PVC roof every spring and fall, and after major storms. Look for seam separations, ponding water, or surface debris that could damage the membrane.
2. Clean the surface regularly: Wash the PVC roof at least once a year with non-abrasive cleaners to remove dirt, grease, and airborne pollutants. This preservative reflects and prevents membrane discoloration.
3. Limit foot traffic: Install designated walkway pads in high-traffic PVC roofing areas, especially around HVAC units and vents, to reduce wear and tear from foot traffic.
4. Keep drains and gutters clear: Ensure all roof drainage components are free of leaves, sediment, and obstructions to prevent ponding water, which accelerates membrane aging.
5. Trim nearby trees: Overhanging branches can drop sharp debris or sap that may compromise the PVC roofing surface. Keep vegetation at least 3 feet away from the roof edge.
6. Use compatible materials for repairs: If patching is needed, always use PVC-compatible materials and heat-weld patches. Avoid using tar, asphalt, or incompatible sealants that can chemically degrade the membrane.

What Are The 6 Ways Of PVC Roofing Damages?

Here are six common causes of PVC roofing damage we’ve encountered on the field

1. Improper PVC roofing seam welding
2. Punctures from sharp objects on PVC roofing
3. UV Degradation in aged membranes
4. Plasticizer migration
5. Poor drainage and ponding water on the PVC roofing
6. Chemical Exposure on the PVC roofing