How Long Does a Flat Roof Last?

flat roof is a popular choice for many property owners due to its modern aesthetic and efficient use of space. However, the longevity of a flat roof tends to be a common concern. To help address this question, we’ll explore the factors influencing the lifespan of a flat roof, as well as tips for prolonging it.

The lifespan of a flat roof can vary considerably, with some materials tending to last around 10-15 years, while others such as EPDM rubber are known to last over 50 years. The average lifespan for a flat roof is between 25 and 30 years, but this can be influenced by the material used, the quality of installation, and climatic conditions. Proper maintenance and regular inspections are essential for maximizing the lifespan of a flat roof.

Taking these factors into account, it’s clear that the longevity of a flat roof is largely dependent on the choices made during its construction and the ongoing care provided. By staying informed about the lifespan of different materials and following best practices for installation and maintenance, property owners can significantly influence the longevity of their flat roof.

flat roofing garden

Lifespan Factors for Flat Roofs

Flat roofs have a varied lifespan, with some lasting 10-15 years and others holding up for 30-50 years. Several factors contribute to the longevity of a flat roof. In this section, we will discuss the impact of materials and installation, weather and environmental effects, and the importance of maintenance and repair.

Impact of Materials and Installation

The choice of material has a significant effect on the lifespan of a flat roof. Traditional materials might lead to a shorter lifespan, whereas modern options like EPDM rubber can extend the roof’s durability up to 50 years. Quality installation also plays a major role, as poor workmanship may result in the need for frequent repairs or even replacement.

Weather and Environmental Effects

Weather conditions and the general environment can greatly impact the lifespan of a flat roof. Factors to consider include:

  • Sun exposure: Ultraviolet (UV) rays from the sun can cause materials to deteriorate over time.
  • Moisture and water pooling: Without proper slope or drainage, water might accumulate on the roof, potentially causing decay.
  • Wind and rain: Strong winds and heavy rain can stress materials or cause watertight seals to deteriorate.
  • Temperature fluctuations: Swings in temperature can cause materials to expand and contract, leading to potential damage.
  • Trees and location: Falling branches or debris from nearby trees can damage the roof surface, and the general location can affect the roof’s exposure to weather conditions.

Maintenance and Repair Importance

Undoubtedly, maintenance and repair are key factors in ensuring a flat roof’s longevity. Regular maintenance, including inspections and routine upkeep, helps identify potential problems before they become major issues. A lack of maintenance can lead to:

  • Accumulation of dirt and debris, hindering proper drainage and increasing the risk of pooling water
  • Deterioration of flashing, leading to leaks and water damage
  • Poor ventilation, resulting in trapped moisture and potential rot or decay

Additionally, addressing repairs promptly and correctly can greatly extend the lifespan of a flat roof. By keeping up with routine maintenance and addressing any issues early on, property owners could potentially extend their flat roof’s life beyond the average lifespan.

poor ventilation

Types of Flat Roofing Materials and Their Longevity

EPDM Rubber Roofs

EPDM (ethylene propylene diene monomer) rubber roofs are a popular choice for flat roofs due to their durability and cost-effectiveness. They are resistant to weather-related issues such as cracking and leaks, and can last up to 30 years with proper maintenance. EPDM rubber roofs have the advantage of being low-maintenance and easy to repair, making them a practical choice for many building owners.

TPO and PVC Membranes

TPO (thermoplastic olefin) and PVC (polyvinyl chloride) membranes are other synthetic options, known for their durability and flexibility in varying weather conditions. These materials have a lifespan of around 25 to 30 years. Both materials are energy-efficient, reflecting sunlight to help reduce energy costs. TPO and PVC membranes are also eco-friendly – TPO can even be recycled at the end of its lifespan, making it an excellent choice for green roofs.

Modified Bitumen and Tarmac

Modified bitumen is a blend of bitumen (tarmac) and polymers that create a durable and flexible roofing material. It is commonly applied in a torch-on or hot mop method, which requires professional installation. The lifespan of modified bitumen roofs is around 20-30 years. Tarmac, on the other hand, is a widely-used, affordable option. The expected lifespan of a tarmax-based flat roof is approximately 15-25 years, depending on the quality of materials and installation.

Concrete and Metal Roofs

Concrete and metal roofs are known for their extreme durability and longevity, often outlasting other materials. Concrete roofs can last up to 50 years with proper maintenance, and they provide excellent insulation. Metal roofs, such as those made from aluminium, steel or copper, can last anywhere from 30-50 years, depending on the specific material and installation quality.

Here’s a brief comparison of the types of flat roofing materials:

FeatureEPDM RubberFelt RoofingGRP (Fibreglass)Single Ply (PVC/TPO)
Lifespan40-50 years10-15 years20-30 years20-30 years
Installation ComplexityLowModerateHighModerate
DurabilityGoodModerateVery GoodGood
Energy EfficiencyModerateLowModerate-HighHigh
Weather ResistanceExcellentModerateExcellentGood
Repair EaseEasyDifficultModerateModerate


Bedfordshire Property Services proudly utilizes ClassicBond EPDM, ClassicBond Pro™, and RESITRIX® membranes for our roofing solutions, all of which boast an impressive life expectancy of up to 50 years.

To further enhance the value offered to our clients, we have participated in specialised training courses, enabling us to provide an exclusive 20-year guarantee on the EPDM installations. This guarantee underscores our commitment to delivering high-quality roofing that customers can rely on for decades.

By choosing Bedfordshire Property Services, property owners benefit from the combination of top-tier materials and expert installation, ensuring a durable and reliable roof that stands the test of time.

rubber roof with skylight

Signs and Causes of Flat Roof Deterioration

Identifying Common Damages

When it comes to flat roofs, some common signs of damage and deterioration include leakscrackingpoolingblistering, and sagging. It’s important to address these issues promptly. Regular maintenance can help you spot potential problems and prevent extensive damage.

  • Leaks: Moisture intrusion can occur around seams, holes, or punctures in the roofing material. This can lead to damage to insulation and metal components, which can cause rust and weakening of the structure.
  • Cracking: As flat roofs experience exposure to the elements, the felt or tarmac may develop cracks. These can allow moisture to penetrate the roof, leading to further wear and potential leaks.
  • Pooling: Poor drainage or debris build-up can cause water to accumulate on a flat roof, leading to a range of issues such as moss growth and damage to the waterproofing materials.
  • Blistering: Heat build-up may cause blistering in the roof surface, indicating trapped moisture and potentially weakening the material.
  • Sagging: Insufficient supports or waterlogged insulation can cause roof sections to sag, which may lead to pooling and other damage.

Contributing Factors to Flat Roof Wear

Various factors can contribute to the deterioration of a flat roof. Being aware of these factors is crucial for extending the roof’s lifespan and minimizing the need for repairs:

  1. Age: Over time, materials like felt and tarmac lose their durability, making the roof more prone to damage.
  2. Maintenance: Regular maintenance helps identify and address issues before they escalate. This includes inspecting seams, clearing debris from gutters, and ensuring proper drainage.
  3. Improper installation: Incorrect installation can lead to poor performance, reduced durability, and a higher likelihood of repairs.
  4. Weather conditions: Exposure to harsh weather, like strong winds, heavy rain, and extreme heat or cold, can speed up the deterioration process.
  5. Moss and algae: The build-up of moss or algae on the roof surface can cause damage to the underlying materials, leading to potential leaks and water damage.
flat roofing repair

Replacing or Repairing Your Flat Roof

When to Repair vs. Replace

To determine whether a repair or replacement is necessary, consider these factors:

  • Age of the roof: Older roofs are likely nearing the end of their life expectancy, so replacing them might be a more cost-effective option in the long run.
  • Extent of damage: Smaller, isolated issues can usually be resolved with repairs, whereas widespread or severe damage may warrant a full roof replacement.
  • Energy costs: Older roofs may contribute to higher energy costs due to poor insulation, making replacement a smart choice for reducing future expenses.
  • Foot traffic: Some flat roofs experience regular foot traffic, which can accelerate wear and tear. In these cases, more frequent repairs or a durable replacement may be necessary.

Choosing the Right Professional and Materials

Selecting a reputable roofing company and quality materials will ensure your flat roof’s longevity and durability. When comparing companies, consider the following:

  • Experience with flat roofs: Look for a company who has a proven track record of working with flat roofing materials and systems.
  • Building regulation compliance: The company should be familiar with local building regulations and ensure that the installation or repair complies with these guidelines.
  • References: Ask for references or testimonials from previous clients to verify their expertise.

Furthermore, there are various roofing materials available for flat roofs:

  1. Metal roofs: These roofs, like standing seam metal roofing, offer durability and long lifespans, often spanning 30-50 years.
  2. PVC and TPO membranes: Both PVC and TPO membranes are lightweight, versatile, and UV-resistant, lasting around 20-30 years.
  3. Concrete: Concrete roofs can offer excellent longevity, with some lasting upwards of 50 years. However, they require reinforced structures to support their weight.
  4. Roofing tiles: Tiles, such as slate or clay, can also provide long-lasting flat roofing solutions, with lifespans often exceeding 50 years.