Felt roofing remains one of the most popular and affordable flat roofing systems in the UK – but how long does it actually last? Whether installed on a home extension, garage, or commercial building, the lifespan of a felt roof depends on several key factors including materials, installation quality, and ongoing maintenance.
At Astral Roofing, we’ve installed and maintained hundreds of built-up felt roofs (BUFR) across Hertfordshire and surrounding areas. Here’s everything you need to know about how long your felt roof should last and how to extend its life.
Average Lifespan of a Felt Roof
A well-installed, high-quality built-up felt roof can last between 20 and 30 years, and in some cases even longer with regular maintenance.
However, the actual lifespan can vary based on:
- Material type: Modern polyester-reinforced bitumen felts last significantly longer than older tar-based felts.
- Number of layers: A traditional three-layer system (base, underlay, and cap sheet) offers the best protection and durability.
- Installation quality: Professionally installed roofs are more resilient to weathering, leaks, and thermal movement.
- Exposure: Roofs exposed to constant sunlight or extreme temperature changes may deteriorate faster.
- Maintenance: Routine inspections and minor repairs help prevent premature ageing and water ingress.
Factors That Shorten Felt Roof Lifespan
While modern BUFR systems are durable, certain issues can reduce longevity if not addressed promptly:
- Poor drainage: Standing water (ponding) can weaken the felt over time and cause cracking.
- UV damage: Prolonged exposure to sunlight can dry out bitumen and lead to brittleness.
- Temperature fluctuations: Expansion and contraction cycles may cause surface blisters or splits.
- Improper installation: Poor adhesion, uneven layering, or unsealed joints increase the risk of leaks.
- Neglect: Skipping annual maintenance checks often leads to unnoticed wear and larger repairs later on.
Signs Your Felt Roof Needs Attention
Knowing when your felt roof requires repair or replacement can save you money and prevent water damage. Look out for these common warning signs:
- Cracks, splits, or lifting edges
- Blistering or bubbling on the surface
- Ponding water that remains after rainfall
- Damp spots or leaks inside the property
- Moss or plant growth
- Discolouration or patches of exposed underlay
If you notice any of the above, it’s best to book a professional roof inspection before the problem worsens.
How to Extend the Life of Your Felt Roof
The good news is that a felt roof’s lifespan can be significantly increased through proper care and maintenance.
Here are a few essential tips from Astral Roofing’s flat roofing specialists:
- Schedule annual roof inspections. Detect early signs of wear before they lead to leaks.
- Keep gutters and outlets clear. Blocked drainage increases standing water and stress on the roof.
- Address minor cracks promptly. Small patch repairs can prevent costly replacements.
- Remove moss and debris. Organic build-up traps moisture and accelerates deterioration.
- Consider a protective coating. Reflective coatings can reduce UV damage and extend service life.
Our team offers planned roof maintenance programmes designed specifically for flat roofing systems, including built-up felt, GRP, and EPDM.
When to Replace a Felt Roof
Even with good maintenance, every roof eventually reaches the end of its lifespan. You may need a felt roof replacement if:
- Repairs are becoming frequent or costly
- Water damage is visible inside the building
- The roof feels soft or unstable underfoot
- Large sections show blistering or delamination
- The roof is over 25 years old
A professional roof survey from Astral Roofing can determine whether your roof can be repaired or if replacement is the most cost-effective option.
Expert Felt Roof Services
If you’re unsure about the condition of your felt roof, Astral Roofing can help. We provide expert installation, repair, and maintenance of built-up felt roofing for residential and commercial properties throughout London, Hertfordshire and neighbouring counties.
Our experienced roofers use only high-performance materials to ensure your roof remains durable, watertight, and built to last.
Contact Astral Roofing today to book your flat roof inspection or request a free, no-obligation quote.
