Cost to Replace a Flat Roof Per Square Foot

Pricing Guide & Best Roofing Options

Understanding the Cost of Flat Roof Replacement

Replacing a flat roof is a significant investment, but understanding the cost per square foot can help homeowners and businesses make informed decisions. Whether you are dealing with leaks, structural damage, or an aging roof, a replacement ensures safety, energy efficiency, and long-term durability.

The average cost to replace a flat roof varies based on several factors, including:

  • Material selection (EPDM, TPO, Fibreglass, PVC, etc.)
  • Labor costs based on location and complexity
  • Insulation, waterproofing, and additional features
  • Size of the roof and accessibility challenges

This guide provides a detailed breakdown of costs, the best materials, and where to find professional roofers to ensure you get the best value for your investment.

Factors That Influence Flat Roof Replacement Costs

1. Type of Roofing Material

The cost of materials varies significantly. Some materials, like EPDM and torch-on felt, are affordable and widely used, while fibreglass and PVC are premium options with higher price tags.

2. Roof Size & Complexity

Most roofing contractors charge per square foot, with prices ranging from $4 to $16 per square foot depending on materials and labor. Larger roofs require more materials, more labor, and additional reinforcements, increasing the total cost.

3. Labor Costs

Professional roofers typically charge between $3 and $8 per square foot for installation. Costs can be higher in urban areas or for complex roof designs requiring specialized expertise.

Best Flat Roofing Materials & Their Replacement Costs

1. EPDM Rubber Roofing

EPDM (Ethylene Propylene Diene Monomer) is a durable synthetic rubber material commonly used for flat roofs.

  • Cost: $5 – $10 per square foot
  • Benefits:
    • Affordable and long-lasting (20+ years)
    • Resistant to UV damage and extreme weather
    • Easy to install with minimal maintenance
  • Use Case:
    Best suited for residential homes, commercial buildings, and garages looking for a budget-friendly roofing solution.

2. Fibreglass (GRP) Roofing

Fibreglass (GRP) is a highly durable, lightweight roofing material with excellent waterproofing properties.

  • Cost: $8 – $14 per square foot
  • Benefits:
    • Seamless, leak-proof finish
    • Resistant to UV rays and fire
    • Long lifespan of 25+ years
  • Use Case:
    Ideal for modern residential properties and commercial buildings that require a sleek, durable, and waterproof roof.

3. TPO Roofing

TPO (Thermoplastic Polyolefin) is an energy-efficient roofing material used in both residential and commercial settings.

  • Cost: $7 – $12 per square foot
  • Benefits:
    • Reflects sunlight, reducing energy costs
    • Durable and resistant to tears and punctures
    • Eco-friendly with recyclable materials
  • Use Case:
    Perfect for large commercial buildings, energy-efficient homes, and environmentally conscious projects.

4. Torch-On Felt Roofing

Torch-on felt roofing is a traditional and affordable flat roofing material known for its strong waterproofing properties.

  • Cost: $4 – $8 per square foot
  • Benefits:
    • Budget-friendly and widely available
    • Multiple layers for extra protection
    • Suitable for garages, sheds, and extensions
  • Use Case:
    Best for budget-conscious homeowners and low-cost roofing projects.

5. PVC Roofing

PVC (Polyvinyl Chloride) is a premium flat roofing option known for its chemical resistance and durability.

  • Cost: $10 – $16 per square foot
  • Benefits:
    • Highly resistant to chemicals and fire
    • Long lifespan of 30+ years
    • Energy-efficient and recyclable
  • Use Case:
    Ideal for factories, restaurants, and high-end residential projects.

Benefits of Replacing a Flat Roof

1. Increased Energy Efficiency

Modern materials like TPO and PVC reflect heat, reducing cooling costs and improving indoor comfort.

2. Enhanced Waterproofing & Protection

Newer roofing systems provide superior leak protection, preventing costly water damage and structural decay.

3. Higher Property Value

Replacing an old or damaged flat roof increases home value and improves the aesthetic appeal of your property.

Use Cases: When Should You Replace Your Flat Roof?

1. Severe Leaks & Water Damage

If your roof has persistent leaks, replacing it with a high-quality, waterproof system prevents further damage.

2. Aging & Deterioration

Most flat roofs last 20 to 30 years. If your roof is cracking, blistering, or sagging, it’s time for a replacement.

3. Increased Energy Costs

If your energy bills are rising, upgrading to TPO or PVC roofing can improve insulation and reduce costs.

How to Find the Best Roofing Contractor

1. Check Certifications & Reviews

Look for certified roofers with positive customer feedback on platforms like:

  • Checkatrade (UK) – Find Trusted Roofers
  • HomeAdvisor (US) – Hire Local Contractors
  • Angi (Angie’s List) – Compare Roofing Services

2. Request Multiple Quotes

Get at least three quotes to compare pricing and services.

3. Ask About Warranties

Professional roofers should offer 20+ years of warranty on materials and installation.

Where to Buy Flat Roofing Materials & Find Contractors

Buy Roofing Materials

  • EPDM Roofing – Shop EPDM Materials
  • Fibreglass Roofing – Order GRP Roofing
  • TPO Roofing – Get TPO Systems

Hire a Roofing Contractor

  • Checkatrade (UK) – Find Roofers
  • HomeAdvisor (US) – Hire Pros
  • Angi (Angie’s List) – Compare Services

Frequently Asked Questions

1. How much does it cost to replace a flat roof per square foot?

The average cost ranges from $4 to $16 per square foot, depending on the material, labor, and additional features.

2. What is the best material for a flat roof?

For affordability, EPDM is a great choice. For longevity, fibreglass (GRP) and PVC offer premium durability.

3. How long does a flat roof last?

A well-maintained flat roof lasts 20 to 50 years, depending on the material used.

Final Thoughts

Understanding flat roof replacement costs helps you make an informed decision. Compare materials, get quotes, and hire trusted professionals to ensure a high-quality installation. Ready to replace your roof? Find top-rated contractors today!