How Do We Secure Solar Panels to Your Roof?

Solar panels are a fantastic way to gain energy independence, reduce your carbon footprint, and potentially save significantly on your energy bills. At 21 Degrees, we're passionate about helping homeowners and businesses make this transition smooth, creating energy-efficient environments. 

But questions we often hear are: "How exactly do you attach those panels to my roof? Is it safe? Will it cause leaks?" These are of course valid concerns because your roof is one of the most critical parts of your property. 

Rest assured, installing solar panels is a well-established process, and when done correctly by experts like us, it's incredibly safe and secure. This guide will walk you through how we secure solar panels, protecting the long-term integrity of your roof. 

Know Your Roof Type: the Foundation of a Solid Installation

Before any installation begins, the most crucial step is assessing your roof. Not all roofs are created equal, and understanding its condition and structure is fundamental to a safe and effective solar panel installation. 

• Safety: The system needs to be securely anchored to withstand wind, rain, and snow for decades. 
• Integrity: We need to ensure the roof can comfortably handle the additional weight of the panels and mounting system without compromising its structure. 
• Longevity: Installing panels on a roof nearing the end of its life isn't wise. It's best to address any necessary roof repairs or replacements before installing solar panels to avoid complications later. 

What Makes a Roof Suitable?

Our team conducts a thorough assessment, looking at several key factors: 

• Structural Integrity: We inspect the roof structure (rafters, trusses, sheathing) to confirm it's sound and can support the added load. This often involves a structural engineer's assessment, especially for larger systems or older properties. They calculate the roof's load-bearing capacity against the weight of the panels, mounting, and potential snow load. 
• Roof Condition & Material: Is the roofing material itself (tiles, slate, metal, asphalt) in good condition? While installations are possible on most common UK roof types like tile, slate, and metal, some materials might require specialised techniques or may be unsuitable (like thatch). The roof should ideally have a significant lifespan remaining. 
• Roof Size and Space: We measure the available roof area to determine how many panels can fit. A typical 3-5kW UK home system might need around 10-16 panels, requiring roughly 20 m² of suitable space. 
• Orientation and Pitch: South-facing roofs offer the best energy production in the UK. However, east and west-facing roofs are also highly effective. The ideal pitch (angle) is typically between 30-40 degrees, but systems can be adapted for flatter or steeper roofs. On flat roofs, mounting frames are used to achieve the optimal tilt. 
• Shading: We assess potential shading from trees, chimneys, neighbouring buildings, or other obstructions, as significant shading can reduce the system's output. Sometimes, optimisers or micro-inverters can help mitigate the effects of partial shading. 

 Only once we're confident your roof is suitable will we proceed with a tailored system design. 

The Anatomy of a Secure Solar Mounting System

So, what holds the panels in place? A specialised mounting system (also called racking) is used. Think of it as the skeleton that supports your solar array. 

Key components typically include: 

• Roof Attachments (Hooks/Brackets): These are strong, corrosion-resistant fixings (usually stainless steel or aluminium) that are securely bolted directly into the roof rafters or trusses – the strong structural beams beneath your roof covering. This ensures the load is transferred to the strongest part of your roof. 
• Flashing: Where the roof attachments penetrate the roof covering (e.g., where tiles are lifted to access rafters), flashing is installed. This is a weatherproof seal (often metal or specialised rubber/plastic) designed to integrate seamlessly with your existing roofing material and prevent any water ingress. Effective waterproofing is paramount. 
• Mounting Rails: These are long sections (usually aluminium) that attach to the roof hooks/brackets. They create a level and secure platform running across the roof upon which the solar panels will sit. 
• Module Clamps: These specialised clamps hold the solar panels securely onto the rails. There are usually 'mid-clamps' (between panels) and 'end-clamps' (at the ends of rows). 

This entire system is designed and engineered to be incredibly robust, resisting wind uplift and weather forces for the lifetime of the system (often 25 years or more). 

How Do Solar Panels Work?

Before we dive into the fixing process, let's quickly refresh how panels generate electricity. It's quite amazing science, made simple: 

• Sunlight Hits: Solar panels are made up of photovoltaic (PV) cells, usually made from silicon. When sunlight (photons) hits these cells, it excites electrons within the silicon atoms, causing them to move. 
• DC Electricity Created: This movement of electrons creates a direct current (DC) electricity. 
• Inverter Magic: Your home appliances run on alternating current (AC) electricity. So, the DC electricity flows from the panels through wiring to a crucial component called an inverter. The inverter converts the DC electricity into usable AC electricity. 
• Powering Your Home: This AC electricity then flows to your consumer unit (fuse box) and powers your home. 
• Excess Energy: If the system generates more electricity than you're using, it can be stored in a battery (if you have one) for later use or exported to the national grid. 

How We Secure Solar Panels to Your Roof

While every project is tailored, here's a typical step-by-step overview of how our expert, in-house teams install your “On-Roof” system safely and securely: 

• Safety First - Scaffolding: Before any roof work begins, appropriate scaffolding is erected around the work area. This ensures the safety of our installation team and allows safe access to your roof. This can sometimes take a significant portion of the first day. 
• Roof Preparation & Marking: We carefully lift specific roof tiles or slates in the precise locations where the roof anchors need to be fixed. The layout for the panels and mounting system, determined during the design phase, is marked out accurately on the roof. 
• Installing Roof Attachments & Flashing: The roof hooks or brackets are securely bolted directly into the roof rafters. This is a critical step ensuring the entire system's weight is supported by the roof's main structure. Depending on the type of tile or slate coving the roof sometimes weatherproof flashings are installed around each anchor point, completing the watertight seal. We take waterproofing extremely seriously, especially given the UK climate. 
• Mounting Rail Installation: The aluminium mounting rails are attached to the installed roof anchors. We ensure they are perfectly level and aligned according to the design plan, creating the secure framework for the panels. 
• Panel Placement & Securing: The solar panels are carefully lifted onto the roof (often using specialised equipment) and placed onto the mounting rails. They are then secured tightly using the mid and end clamps. We double-check every connection to ensure the panels are firmly fixed and aligned for optimal sun exposure and can withstand high winds. 
• Wiring the Panels: The panels are wired together (usually using specific connectors like MC4) according to the system design (either in series or parallel). This wiring is then routed safely and neatly (often through the loft space or external conduit) down to the location chosen for the inverter. 
• Inverter & Electrical Connections: The inverter is installed (often in a loft, garage, or utility room – a cool, ventilated spot is best). Our qualified electricians then connect the wiring from the panels to the inverter and connect the inverter's AC output to your home's consumer unit (fuse box). A generation meter is also installed to track your system's production. If you're having a battery installed, it's connected at this stage too. All electrical work complies with UK wiring regulations (BS 7671). 
• System Testing & Commissioning: Once everything is connected, we perform thorough electrical tests and safety checks. The system is switched on, and we verify that everything is operating correctly, panels are generating power, and the inverter is functioning as expected. 
• Handover & Documentation: We'll walk you through the system, explain how it works, and provide you with all the necessary documentation, including warranties and certifications (like your MCS certificate, which you'll need for SEG export tariffs). 

Depending on the system size and complexity, the roof work and electrical connections usually take 1-3 days after scaffolding is up. 

We can also install Solar PV Panels “In-Roof”. This is usually done when a property is newly built or requires re-roofing. In this scenario the tiles are completely removed and either a slim tray or even the panels themselves become the weatherproof covering. The roof tiles are then installed around them along with lead or aluminium flashings completing the fully waterproof finish.  

Weatherproofing and Maintenance

A key concern is preventing leaks. As mentioned, proper installation of flashing around roof anchor points is critical. Our experienced installers use high-quality materials and proven techniques to ensure a watertight seal that lasts. The mounting systems themselves are designed to withstand decades of UK weather, using corrosion-resistant materials like stainless steel and aluminium. 

What About Maintenance? 

Solar panels are remarkably low maintenance. 

• Cleaning: In the UK, regular rainfall is often sufficient to keep panels clean. However, in particularly dusty areas or if significant bird droppings accumulate, performance might slightly decrease. If needed, cleaning is straightforward – usually involving water and a soft brush. We can advise if cleaning is necessary for your specific situation. Many homeowners find they rarely, if ever, need to clean their panels. 
• Inspections: While the systems are designed for longevity, periodic visual inspections are a good idea. We also offer monitoring systems that can help detect any potential issues early on. 

Frequently Asked Questions

Here are answers to some common questions: 

• Will the panels damage my roof? When installed correctly by qualified professionals like 21 Degrees, solar panels do not damage your roof. The mounting system is designed to distribute weight evenly and attach to the strong rafters, and meticulous waterproofing prevents leaks. Improper installation by unqualified individuals could cause damage, which is why choosing a reputable installer is vital. 
• What if I need to replace my roof later? This is why assessing roof condition before installation is crucial. If your roof needs replacing soon, it's best done first. If replacement becomes necessary years down the line, the solar panels and mounting system would need to be temporarily removed and then reinstalled. 
• How do you ensure no leaks? Through careful installation techniques, using high-quality roof hooks/brackets with integrated flashing, and applying additional appropriate sealants where necessary. Our experienced teams understand how different types of roofs work and ensure every penetration is properly sealed. 
• Can panels be moved or expanded later? Moving panels is possible but involves reinstalling the mounting system. Expanding the system is often feasible, provided you have suitable roof space and the inverter capacity can handle additional panels. We can discuss future expansion possibilities during the initial design phase. 
• How many solar panels do I need? This depends on your energy consumption, available roof space, roof orientation/pitch, and budget. Our team performs a detailed assessment to recommend the optimal system size for your specific needs. 
• How long does it take to install solar panels? Including scaffolding setup, the entire process typically takes around 2-3 days for a standard residential installation. The actual time spent installing panels and electrics on the roof is often just one day. 

Smart Solar That Works With Your Home

At 21 Degrees, we deliver tailored energy solutions designed for optimal efficiency, health, and comfort. We understand that investing in solar is a significant decision, and we're committed to being your trusted partner throughout the process. 

Our full-circle approach means we handle everything – from initial assessment and bespoke system design to sourcing superior-quality products and executing flawless installations with our own expert teams. We pride ourselves on straightforward communication, honesty, and ensuring every recommendation is genuinely in your best interest. 

We believe in empowering you with the knowledge to make informed decisions, creating systems that not only save you money and reduce environmental impact but also enhance your property's long-term value and wellbeing. 

Ready to explore how solar energy can transform your home or business? 

Let's start the conversation. Get in touch for a no-obligation consultation or request a quote today and let us design a smart solar solution that works perfectly for you.