What Are the Best Materials for Flat Roofs?

Choosing the right material for a flat roof is crucial to ensuring durability, cost-effectiveness, and suitability for specific needs. From traditional options like roofing felt to more modern solutions like EPDM membranes and green roofs, this guide offers an in-depth look at the best materials for flat roofs. Ultimately, the best material for your flat roof depends on a variety of factors including budget, climate, intended use, and aesthetic preferences.

To help you make an informed choice, we will run through some of the top flat roof materials available. We’ll examine the pros, cons, and ideal applications for each material, helping you make an informed decision for your property.

Roofing Felt

Roofing felt, a traditional material, is made from a blend of natural and synthetic fibres coated in bitumen. It is commonly used as an underlayer for other roofing materials but can also serve as a standalone covering for flat roofs.

Pros

Economical option, offering a cost-effective solution for roofing projects.

Readily available in many stores, making it convenient to purchase.

Relatively simple to repair, allowing for quick fixes of minor damage.

Cons

Generally has a shorter lifespan than more modern materials, requiring more frequent replacements.

Susceptible to damage from UV rays and extreme weather, including heavy rain and high winds.

Suitable for:

Temporary structures or areas with less exposure to severe weather.

Budget-conscious projects where cost is a significant consideration.

 

Shed Felt

Shed felt is a specific type of roofing felt designed for outdoor buildings such as sheds and garages. It’s lighter and more flexible than standard roofing felt, making it easier to work with on smaller structures.

Pros

Tailored for outdoor buildings, offering appropriate protection for sheds and similar structures.
More affordable than many other roofing materials, making it ideal for small projects.
Installation is straightforward, making it a good choice for DIY enthusiasts.

Cons

Not designed for high traffic areas or residential spaces, limiting its use to outbuildings.
Prone to wear and tear, necessitating regular checks and maintenance to ensure longevity.

Suitable for:

Sheds, garages, and other outbuildings that do not require the highest level of durability.

 

Torch-on Felt

Torch-on felt roofing involves layers of modified bitumen melted together with a torch to create a watertight seal. This method offers enhanced durability and waterproofing capabilities over traditional felt roofing.

Pros

Offers enhanced durability and a waterproof seal, making it suitable for more demanding environments.
Provides excellent resistance to tearing and punctures, helping to ensure a long-lasting roofing solution.
With proper maintenance, it can have a lifespan that rivals more expensive materials.

Cons

The installation process involves open flames, requiring skilled professionals to ensure safety and effectiveness.
The initial installation cost is higher than that of traditional roofing felt, reflecting its superior performance.

Suitable for:

Residential and commercial buildings that need a durable and reliable flat roofing solution.

 

Self-Adhesive Felt

Self-adhesive felt roofing is a modern alternative to traditional torch-on methods, featuring a sticky underside that bonds to the roof surface without the need for heat. It’s particularly favoured for its ease of installation and safety.

Pros

Installation is safe and straightforward, eliminating the need for hot work and specialised tools.
Offers good waterproofing capabilities, providing reliable protection against the elements.
Particularly suited for small repairs or DIY projects due to its ease of use.

Cons

In cold climates, the adhesive may not perform well, potentially compromising the roof’s integrity.
Generally considered less durable than torch-on options, which may limit its suitability for certain projects.

Suitable for:

Quick repairs and small DIY projects where ease of installation is a priority.

 

EPDM Membranes

Ethylene Propylene Diene Monomer (EPDM) is a synthetic rubber roofing membrane known for its outstanding durability, flexibility, and resistance to extreme weather conditions. It’s a popular choice for environmentally conscious projects.

Pros

Highly durable, with a life expectancy of up to 50 years under optimal conditions.
Resistant to extreme weather, including UV light, heat, cold, and rain, making it ideal for a wide range of climates.
Environmentally friendly, both in production and disposal, with recyclable properties.

Cons

Installation typically requires professional expertise to ensure optimal performance, adding to project costs.
The material cost is higher than some traditional options, although this is offset by its longevity and low maintenance needs.

Suitable for:

Both residential and commercial projects where long-term durability and environmental impact are key considerations.

 

GRP Fibreglass Roofing

Glass Reinforced Plastic (GRP) fibreglass roofing is a strong, waterproof material made from polyester resin reinforced with glass fibres. It’s known for its durability and versatility in finishing options.

Pros

Exceptionally long-lasting and waterproof, providing a robust solution for flat roofs.
Virtually maintenance-free once installed, saving time and money over the roof’s lifespan.
Aesthetically versatile, available in various colours and finishes to match the building’s design.

Cons

The cost of materials and installation is on the higher end, reflecting its premium quality and performance.
Requires skilled installation to ensure the integrity of the waterproof seal and overall durability.

Suitable for:

High-end residential projects and commercial buildings where durability and aesthetic appearance are paramount.

 

PVC

Polyvinyl Chloride (PVC) roofing is a single-ply roofing solution made from a flexible, thermoplastic material. It’s known for its strength, durability, and resistance to chemicals and fire.

Pros

Offers excellent strength and durability, with a resistance to chemical exposure and fire.
Lightweight, reducing the structural load on buildings and making it suitable for a variety of projects.
Known for its long service life, providing a cost-effective solution over its lifespan.

Cons

Performance can be affected by low temperatures, potentially leading to brittleness and cracks.
The initial cost may be higher than some materials, although this is balanced by its longevity and low maintenance.

Suitable for:

Commercial and industrial buildings, especially those requiring chemical resistance or have significant equipment on the roof.

 

Green Roofs

Green roofs are covered with vegetation and soil, or a growing medium, planted over a waterproofing membrane. They offer excellent insulation, reduce stormwater runoff, and provide habitats for wildlife.

Pros

Provides excellent thermal insulation, reducing energy costs for heating and cooling.
Supports local ecosystems by creating habitats for wildlife and helping to improve air quality.
Absorbs rainwater, reducing runoff and the risk of flooding in urban areas.

Cons

Requires a significant upfront investment for installation and the setup of the waterproof membrane and drainage systems.
Maintenance needs are higher than traditional roofs, including watering, weeding, and ensuring the health of the plants.

Suitable for:

Urban and eco-conscious buildings looking to improve sustainability and reduce their environmental footprint.

 

Built-Up Roofs (BUR)

Built-up roofs (BUR) consist of multiple layers of bitumen and reinforcing fabrics that create a finished membrane. They’re known for their durability and are commonly used on low-slope roofs.

Pros

Offers a proven track record of reliability and durability, with some roofs lasting over 20 years.
Excellent at waterproofing, thanks to multiple layers of bitumen and reinforcing fabric.
Can be made to accommodate thermal movement, reducing the risk of cracks and leaks.

Cons

The installation process is labour-intensive and time-consuming, potentially increasing the cost.
The system’s weight requires adequate structural support, which may not be suitable for all buildings.

Suitable for:

Larger commercial or industrial buildings that can support the weight and benefit from the durability of BUR systems.

 

Flat Roof Decks

Flat roof decks are designed to provide usable outdoor living space on top of flat roofs. These can be made from various materials, including wood, composite, or even green roofing systems.

Pros

Enhances the usability of flat roofs, providing space for recreation or green spaces.
Can add significant value to a property by increasing the usable outdoor area.
Offers design flexibility, with materials and finishes that can complement the building’s appearance.

Cons

Design and construction must carefully address water drainage to prevent pooling and leaks.
Regular maintenance is required to ensure the deck surface remains waterproof and the structure remains sound.

Suitable for:

Properties looking to maximise their space with additional outdoor living areas, including residential and commercial buildings.

 

So, which is right for me?

Choosing the best material for your flat roof depends on a variety of factors including budget, climate, intended use, and aesthetic preferences. For durability and eco-friendliness, EPDM membranes and green roofs are excellent choices. Whereas, if you’re looking for cost-effectiveness for smaller structures like sheds, sheds might be ideal. For those prioritising aesthetics and longevity, GRP Fibreglass Roofing and PVC are a great option. It’s crucial to weigh the pros and cons of each material against your specific needs to make the best decision.

 

FAQs

How long does a flat roof last?

The lifespan of a flat roof depends on the material used. Materials like EPDM can last up to 50 years, while traditional felt options may need replacing after 10 to 15 years.

 

Are green roofs more expensive than traditional roofing materials?

Yes, green roofs typically have a higher initial cost due to the materials, installation, and maintenance required. However, they can offer long-term savings through improved insulation and reduced stormwater runoff fees in some areas.

 

What is the most eco-friendly roofing material?

EPDM membranes and green roofs are among the most eco-friendly options. EPDM is recyclable and has a long lifespan, reducing waste. Green roofs provide habitat for wildlife and help to lower urban air temperatures.

 

What is the strongest flat roof material?

When it comes to strength and durability, EPDM (Ethylene Propylene Diene Monomer) rubber roofing is one of the strongest materials available for flat roofs. This synthetic rubber material is known for its resistance to extreme weather conditions. EPDM roofs can last up to 50 years or more with proper installation and maintenance, making them an excellent long-term investment for ensuring the structural integrity of a flat roof. Additionally, PVC and TPO (Thermoplastic Polyolefin) roofing membranes are also known for their strength and durability, offering similar benefits in terms of longevity and resistance to environmental factors.

 

What is the most cost-effective flat roofing material?

Traditional roofing felt, also known as bitumen felt, is often considered the most cost-effective flat roofing material. Roofing felt is relatively inexpensive to purchase and install, making it a popular choice for budget-conscious property owners. While it may not offer the same longevity or resistance to environmental factors as some of the more modern materials like EPDM or PVC, roofing felt can still provide a satisfactory level of protection and durability for several years. Shed felt, a variant of roofing felt designed specifically for sheds and outbuildings, offers a similar level of cost-effectiveness for non-residential applications.

AES Roofing – Flat Roofing Specialists

If you’ve found yourself here while exploring options for the best materials for your flat roof, you might be wondering how AES Roofing can assist you further. As specialists in flat roof repairs, AES Roofing has the expertise and range of options to address your specific needs.

At AES Roofing, we understand that choosing the right material for your flat roof is a significant decision that impacts both the longevity and performance of your roofing system. That’s why we offer a diverse selection of roof coverings, from the traditional felt to modern rubber and durable GRP. Each option provides a different balance of price and longevity.

Furthermore, we’re proud to offer warranties ranging from 6 to 20 years on our various flat roof covering options, with life expectancies stretching from 16 to over 50 years. This gives you peace of mind, knowing that your investment is protected for the long term. Additionally, our flat roofing systems come with a separate insurance underwritten warranty for up to ten years, offering an extra layer of security.

Whether you’re in the initial stages of planning or urgently need assistance with your flat roof, AES Roofing is here to help. Our team of specialists is equipped with the knowledge and experience to guide you through selecting the best material for your flat roof, ensuring that your property is protected, functional, and aesthetically pleasing. Don’t hesitate to reach out to us; a member of our team will be happy to assist you. Contact AES Roofing today on 01905 333697 or complete our online contact form and we will be in touch as soon as possible.