Flat Roof

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Stay Safe & Don't Worry About Exact Numbers! There is no need to climb your roof. Simply estimate the dimensions to your best knowledge. I will personally take precise measurements during a free site visit, and the final price will be calculated using the exact same transparent formula.

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15 Yrs System Warranty 25 Yrs Expected Lifespan
The highly recommended choice for long-term peace of mind. I will install a heavy-duty underlay followed by a premium charcoal mineral top sheet. Welding these two layers together creates a thick, impenetrable shield against the harsh British weather. This system is designed to last at least 15 years, keeping your garage bone-dry and secure.
Tecnatorch SBS Torch-On Mineral Felt Charcoal
Tecnatorch SBS Torch-On Mineral Felt Charcoal

Included in Price

Tecnatorch SBS Torch-On Plain Capsheet Sanded
Tecnatorch SBS Torch-On Plain Capsheet Sanded
Tecnatorch SBS

This SBS-modified sanded felt is the core component that upgrades your roof to a high-performance dual-layer system. It provides a robust, elasticated base that perfectly bonds with the final charcoal cap sheet for maximum strength. This foundation layer allows the roof to expand and contract safely during UK weather extremes, preventing cracks and leaks. Choosing this system ensures the highest level of durability and long-term peace of mind.

Included
Felt drip edge (4 sides Hardboard)
Felt drip edge (4 sides Hardboard)

Installing a hardboard trim around the entire roof perimeter to create sharp, rigid drip edges for the new felt. This solid backing allows the felt to be formed into a neat overhang, rather than a weak curve. It effectively directs rainwater away from the fascia boards and stops water from tracking back underneath the roof. This ensures a clean, professional finish and full perimeter protection.

Included
Bitumen Primer: Material Application
Bitumen Primer: Material Application
Cromar

Applying a bitumen primer is a crucial preparation step before installing the new waterproofing system. This liquid coating seals the existing substrate and locks in any remaining dust. Its main purpose is to create the perfect conditions for the first layer of felt to adhere flawlessly. This guarantees a strong, permanent bond between the treated surface and the felt.

Included
Ladder Access Work (Scaffolding Not Included)
Ladder Access Work (Scaffolding Not Included)

This service includes access using standard ladders or a hook ladder. Many repairs can be carried out efficiently without the need for scaffolding, saving both time and cost. However, safety is always our priority. If site conditions do not allow safe ladder use (e.g. limited space or difficult access), scaffolding may be required and is not included in this price.

Included
Felt drip edge (4 sides Hardboard)
Felt drip edge (4 sides Hardboard)

Installing a hardboard trim around the entire roof perimeter to create sharp, rigid drip edges for the new felt. This solid backing allows the felt to be formed into a neat overhang, rather than a weak curve. It effectively directs rainwater away from the fascia boards and stops water from tracking back underneath the roof. This ensures a clean, professional finish and full perimeter protection.

Included
Bitumen Primer: Material Application
Bitumen Primer: Material Application
Cromar

Applying a bitumen primer is a crucial preparation step before installing the new waterproofing system. This liquid coating seals the existing substrate and locks in any remaining dust. Its main purpose is to create the perfect conditions for the first layer of felt to adhere flawlessly. This guarantees a strong, permanent bond between the treated surface and the felt.

Included
Ladder Access Work (Scaffolding Not Included)
Ladder Access Work (Scaffolding Not Included)

This service includes access using standard ladders or a hook ladder. Many repairs can be carried out efficiently without the need for scaffolding, saving both time and cost. However, safety is always our priority. If site conditions do not allow safe ladder use (e.g. limited space or difficult access), scaffolding may be required and is not included in this price.

Included

Optional Add-ons

This service involves a complete restoration of the existing lead flashing. First, the surface is mechanically cleaned using a wire brush to remove oxidation and debris. We then apply Lead Patination Oil, which protects the metal from weathering and prevents white carbonate staining on your roof. Finally, the brickwork joint is cleaned and resealed using a high-quality specialist lead sealant (silicone) to ensure a long-lasting, watertight finish.

Installation of new Code 4 lead flashing (150mm) to create a secure, watertight seal where the roof meets the brickwork. We professionally fit the lead into the masonry joints and apply Lead Patination Oil to the surface. This protective coating prevents natural oxidation and stops white carbonate streaks from staining your new roof. The joints are finished with high-quality specialist lead sealant, which stays flexible and handles temperature changes better than standard silicone. This method ensures a long-lasting lifespan and reliable protection against the weather.

A surcharge for removing old protective stone chippings from the existing roofing felt. Years of weather exposure cause these stones to melt and bond into a solid crust with the underlying bitumen. Removing them requires intensive physical labour to chip and scrape the surface clean. This crucial step ensures the new roof adheres properly.

Replace weakened or failing garage roof joists to ensure the entire structure remains stable and secure. This is necessary when existing timbers are soft from rot, bowing under weight, or compromised by pests. We provide and install new, high-quality timber joists up to 4 metres long. Simply specify the number of joists required; the price is calculated per unit for a complete installation.

Essential when your roof deck is rotten or sagging. We strip all old felt and timber boards back to the bare joists, creating a clean base for reconstruction. Price includes all labour, professional skip hire delivered to your site, and licensed waste disposal fees. No hidden costs for rubbish clearance. Note: This covers removal only; please also add "New OSB Deck Installation" to your estimate to include the new structural boards.

We create a rock-solid foundation using premium 18mm OSB3 moisture-resistant boards, specifically engineered for structural use in the British climate (BS EN 300 standard). These high-performance boards offer superior strength and durability compared to standard chipboard, ensuring a perfectly flat and stable base for your new roof. Each sheet is precision-fitted and securely fastened to the joists to prevent future movement. Note: This service covers new material and installation only.

15 Yrs Warranty 25 Yrs Lifespan

Preparation and Vapour Barrier: A functional vapour barrier is the most critical step. It stops warm, moist indoor air from rising into the insulation, where it would otherwise condense on the colder upper layers of the roof and cause hidden moisture or rot. In many cases, your existing roofing felt can serve as a reliable vapour barrier if it is in good condition. Insulation Laying and Fixing: We install the 100mm insulation boards onto the prepared base. To maintain the integrity of the vapour barrier underneath, we secure the boards using specialized expanding roofing foam. Mechanical fixings are only used in extreme conditions, such as on very tall buildings or highly exposed coastal sites. Edge Reinforcement (Included in Price): Adding insulation raises the overall roof height by 100mm. Therefore, we install new structural timber rafters of the same thickness around the entire perimeter to reinforce the edges. These timbers and their installation are fully included in the price of this item. Fascia Board Adjustment (Not Included): Please note that because the roof profile is raised, new and deeper uPVC fascia boards are almost always required to aesthetically and functionally cover the new height. These boards are not included in this specific item and are quoted separately. Final Waterproofing: Once the insulation is secured, a new protective system is torch-applied directly on top. This consists of a heavy-duty underlay and a final mineral cap sheet that protects the roof from UV radiation.

A surcharge for removing old protective stone chippings from the existing roofing felt. Years of weather exposure cause these stones to melt and bond into a solid crust with the underlying bitumen. Removing them requires intensive physical labour to chip and scrape the surface clean. This crucial step ensures the new roof adheres properly.

Installation of new Code 4 lead flashing (150mm) to create a secure, watertight seal where the roof meets the brickwork. We professionally fit the lead into the masonry joints and apply Lead Patination Oil to the surface. This protective coating prevents natural oxidation and stops white carbonate streaks from staining your new roof. The joints are finished with high-quality specialist lead sealant, which stays flexible and handles temperature changes better than standard silicone. This method ensures a long-lasting lifespan and reliable protection against the weather.

This service involves a complete restoration of the existing lead flashing. First, the surface is mechanically cleaned using a wire brush to remove oxidation and debris. We then apply Lead Patination Oil, which protects the metal from weathering and prevents white carbonate staining on your roof. Finally, the brickwork joint is cleaned and resealed using a high-quality specialist lead sealant (silicone) to ensure a long-lasting, watertight finish.

Estimate Summary

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Your New Flat Roof in Sussex: Get an Accurate Price in 60 Seconds

Why guess the cost of your flat roof repair or wait endlessly for callbacks? My instant online calculator provides a fully itemised, transparent estimate in just a minute. As an independent roofing specialist dedicated to serving homeowners across Sussex, including Brighton, Hove, and Worthing, I personally guarantee the quality of every installation. The price you see is exactly what it takes to get the job done right.

Smart Insulation: Year-Round Comfort & Energy Efficiency

When replacing your roof, it is the perfect time to consider a 100mm thermal insulation upgrade. This modern solution significantly changes your living experience: it keeps your rooms cool in the summer and prevents massive heat loss in the winter, lowering your energy bills.

My insulation method focuses on long-term durability and structural health:

  • Condensation Prevention: I install a precise vapour barrier to stop warm, moist indoor air from rising into the insulation. This prevents condensation from forming on colder layers, which eliminates the risk of hidden rot and mould.
  • Structural Edge Reinforcement: Adding 100mm of insulation raises the roof profile. To ensure a solid finish, the cost of this upgrade includes new structural perimeter timbers (rafters) to reinforce the edges.
  • uPVC Fascia Adjustment: Please note that because the roof height increases, new and deeper uPVC fascia boards are almost always required to cover the new gap. These are available as a separate add-on in the calculator.

Welcome to Your Personal Project Hub

Choosing my services means you are investing in total peace of mind. Every flat roof project comes with access to a modern, secure Client Portal. It’s your personal command centre designed to keep you informed every step of the way:

  • Live Project Tracking: Follow our progress on a visual timeline. You will always know exactly what stage your flat roof installation is at.
  • Real-Time Photo Log: I upload “before, during, and after” photos directly from your roof, giving you visual proof of the high-quality materials and workmanship.
  • Direct & Instant Chat: Have a quick question? Message me directly through the portal to keep all communication organised in one place.
  • Organised Digital Paperwork: Access your quotes, deposit receipts, warranties, and final invoices anytime you need them.

Why Choose Our Flat Roofing Systems?

Flat roofs in the UK face heavy rain, wind, and harsh UV rays. That is why I focus on heavy-duty, long-lasting solutions like premium SBS Torch-On mineral felt systems. Built to expand and contract safely with the British weather without cracking, these systems guarantee a 100% watertight finish for decades.

Ready to start? Simply enter your roof dimensions and select your preferred setup in the calculator above. Add insulation or other optional extras, and watch your customized estimate update instantly.