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DIY SOLAR PANELS | UK GUIDE. DIY solar flat roof

DIY SOLAR PANELS | UK GUIDE. DIY solar flat roof


    We are happy that Renogy’s DIY community continues to grow with more and more members choosing to trust our products as their go-to choice. This article is dedicated to all you DIY-ers, cutting costs and saving the planet with each solar system you install.

    Now, if you are thinking of setting up a DIY home solar system, this article will help you make the best DIY solar decisions and avoid making common mistakes.

    Here, we will answer most of your burning questions about DIY solar panels. including:

    Please note that the DIY solar panels in this article are manufacturer-made panels suitable for DIY installations. Not solar panels built from scratch by individuals.

    Can you install solar panels yourself?

    The cost of designing, buying, and installing solar for the average household in the UK is around £6000. Of that £6000, approximately 10% goes to the cost of hiring a pro-installer. In other words, hiring a professional installer costs at least £600, which is concerning if you’re on a budget.

    As a result, you end up wondering if you can install solar panels yourself.

    And the answer is YES. You can DIY (do-it-yourself) install your own solar panels.All you need to do is invest your time, energy, and a little bit of elbow grease.

    This lowers your cost of going solar by approximately 10% or more. For most homeowners, this is a worthwhile incentive to invest their time and efforts.

    However, before going the DIY solar panels’ route, here’s what you need to know:

    If you’re not as agile or handy as you used to be, we highly recommend hiring an installer, as rooftop solar installations can be dangerous if you are not careful. No amount of money saved is worth risking your well-being.

    Do not buy substandard components because they’re cheap. Instead, buy premium parts that are priced reasonably. Doing so ensures you get the best value for your money. Without question, we recommend buying renogy solar parts directly from our

    For large solar installations, it’s highly recommended to hire a professional installer.

    In areas with strict PV regulations, a professional installer can help you process permits and other necessary paperwork. Some utilities need a certified electrician’s signature as proof your system can be connected to the grid safely. Besides, when you apply for a Smart Export Guarantee (SEG) from your energy provider, they might need an MCS certification and a DNO (district network operator) approval.

    How much does it cost to install solar panels?

    The cost of installing solar panels will vary depending on:

    The size of your system

    Type of your installation

    The installer you choose

    On average, the cost of hiring a professional installer can range anywhere from £600 to a few thousand pounds. According to the EnergySage Solar Marketplace, the average cost of labour when installing a solar system is approximately 10% of the cost of all your components. If you wanner know how much solar panels are in the UK. click the link.

    So if your components cost around £6000, then the cost of installation will be around £600. Please note that this figure is an estimate and may vary, so it’s best to cross-check with an installer near you.

    DIY solar panel installation process

    There are a few stages you need to take care of before you start your DIY solar panel installation process.

    One of the stages is quite obvious, which is buying the equipment you want to install. However, other lesser-known but important stages are:

    Energy Usage Calculation (load or amount of electricity you use each day)

    Solar Panel System Sizing

    How to install a DIY solar panel system at home?

    The installation process for a DIY solar panel system can be broken down into 6 basic steps:

    Step 1: Calculate Your Daily Energy Usage

    If you’re connected to the grid, and want to find out how much you use daily, you need to look at your utility bills. On your utility bill, you will find the amount of Wh (Watt-hours) or kWh (kiloWatt-hours) used that month. For even better results, use the bills for the last 3 months to work out an average monthly usage. Once you have your monthly usage, divide that figure by the number of days in a month to find your daily usage.

    solar, panels, guide, flat, roof

    Alternatively, you can sum up each of your device’s wattage and the number of hours used to find out the total energy you use daily.Our online solar panel calculator can help you here.

    Step 2: Design Your System

    You need to decide if you are going to substitute all or part of your daily energy usage with solar power. You can choose to build a completely offgrid solar system that will power all your devices without any help from the grid.

    Or, you can choose to build an on-grid solar system, also known as a grid-tied system, that only substitutes a fraction of your daily usage with solar power.

    If you are building an off-grid system, you definitely need a solar lithium battery. On the other hand, an ongrid system can do without a battery bank due to the Smart Export Guarantee (SEG). The only drawback of an on-grid solar installation without solar battery storage is that you won’t have any backup power during emergencies.

    Step 3: Size Your Solar Panels

    Once you know how much power you want to generate with solar, you can calculate how many solar panels you need to produce that much power. We will explain how to size your solar panels later in this article.

    Step 4: Purchase Quality Solar Components

    After determining your daily usage and optimal panel output, you can start buying all the parts you will need for your installation, including:

    Step 5: Install Your Railings, Mounts, and Components.

    Once you’ve gathered all your components, you can start preparing the areas where you will install your components. This usually involves:

    Mounting the railing for your panels on the roof

    Creating or clearing a suitable space for your inverter and battery bank,

    After preparing the installation zones, install the components. This involves:

    Lifting solar panels onto the roof and bolting them to the railings;

    Screwing your inverter onto the wall;

    Finding a safe space for your batteries. The area shouldn’t be exposed to direct sunlight nor extreme temperatures (hot/cold);

    Installing the joining cables and connectors.

    Step 6: Connect your solar to your home’s distribution box

    Once you know which circuits you want to power with solar power, you can choose to join or replace the wires with the power supply of your choice. For example, you can choose to power only your lights and a few sockets, or you can choose to power all your circuits.

    How to size solar panels for your home?

    To size solar panels for your home, you need to know two things:

    Your daily energy usage

    Number of peak sun hours in your area.

    Once you have these figures, you can calculate two things:

    The total power output required from your panels each peak hour. How? Dividing your daily usage by the number of peak sun hours. The answer you get is the amount of power your panels should generate during each peak sun hour.

    The number of panels at each wattage you need to buy to meet the demand. How? Divide the above figure (hourly power needed) by your chosen panel’s wattage. For example, if hourly power is 3000Wh and you choose a 300W panel, you will need 10 (ten) 300W solar panels to meet the 3000W hourly demand.

    What are DIY solar panel kits?

    Solar parts come in different sizes (capacities, wattages, etc.) and they can only work well when matched with other parts of a matching size. Think of it this way, when you’re shopping for clothes in a store with different clothing sizes, you need to pick a t-shirt, jeans, and shoes suited for your size and with each other.

    This is also the case when you are shopping for solar parts that come in different sizes. Therefore, you need to pick solar panels, inverters, batteries, and other parts that are compatible with each other and suitable for your needs.

    That’s where DIY solar panel kits come in.

    A DIY solar panel kit is a set of compatible solar parts that are already hand-picked for you, taking the hassle out of searching for the right parts.

    Buying the right solar kit will save you money and reduce the time it takes you to set up a working solar installation. It also helps you avoid rookie mistakes or costly trial-and-error purchases.

    Renogy has many sizes and types of DIY solar kits;examples include:

    Each of these kits is carefully configured to fit a variety of situations. We also have flexible solar kits suitable for RV or Marine use.

    If you think DIY solar kits are just what you need, check out this link to all of Renogy’s solar kits.

    The Pros and Cons of DIY solar panels

    As with most things, there are two things involved when setting up your DIY home solar panels.- the pros and cons.

    It’s up to you to decide if the advantages of DIY solar panels more than offset their disadvantages.

    Pros of DIY solar panels

    Reduces your dependence on the grid supply and gives you more control over your energy.

    Lowers your energy costs as solar is now a cheaper energy source than the grid.

    You get an intimate knowledge of your system during the installation and can troubleshoot most problems.

    Saves money that would otherwise be spent on hiring an installer. You can re-invest this money elsewhere, e.g., buying more components to build an even better system.

    Suitable for most applications, including homes, businesses, RVs, boats, etc.

    Provides an emergency or independent power supply that’s usable even when there’s no grid power.

    Cons of DIY solar panels

    It might reduce your equipment warranties depending on the terms and conditions of your manufacturer.

    Requires investing your time and effort to learn about how to work with electricity and solar equipment.

    DIY installation might be impossible in some regions due to prohibitive local laws.

    It’s more challenging for homeowners outfitting large solar systems. In that case, we recommend hiring a professional installer.

    DIY solar panel building regulations for home

    Regardless if you hire an installer or you carry out a DIY home solar systeminstallation, your solar panel installation needs to follow the standard UK building regulations for your area.

    These regulations typically are:

    Ensure that your roof is strong enough to support your panels

    Mitigating the risk of fire your solar panels pose.

    How to install your solar components correctly to give them improved ventilation.

    Ensuring the entry points of your cables don’t allow moisture into the structure.

    Improving the electrical safety of your installation.

    How to mount your panels and other components securely.

    For more information on the Building regulations for your area, visit the links below:

    Do I need permission for solar panels?

    Sometimes you do and sometimes you don’t. Let me explain why.

    Most of the time, if your panels meet certain criteria and standards, you don’t need to obtain planning permission to install solar panels on your property.

    However in some special cases, which will be listed below, you need to obtain planning permission before installing your panels:

    If your property is a listed building.

    If you live in an area designated as a conservation area.

    If you are going to carry out any major modifications on the building. For example, an increase in size.

    If your solar panels protrude more than 0.2 metres or 20 centimetres from your roof. For example, an installation on a flat roof is typically more than 0,2 metres due to the angled stands.

    If you are carrying out a ground installation with stand-alone panels that is/are:

    c. Located within the grounds of a listed building

    d. Each panel has an area of more than 9m^2

    If any of the above cases apply to you, do not worry. You can still apply for a special planning permission from your local authority.

    To summarize, if the DIY installation of your solar panel system doesn’t involve any major changes to the building – such as changing its size, shape, exterior appearance or other aspects, you likely won’t need special permission from your local authority.

    However, if you want to make some big changes, you might need to get planning permission from your local authority before installation. We highly recommend checking in with your local authority to see if there are any other regulations to follow regarding independent energy generation.

    Monitoring and Maintenance for DIY solar

    A DIY solar system needs regular monitoring and maintenance to ensure that it keeps performing safely and at the highest levels. Fortunately, the level of maintenance your solar system needs is on the low-side. So it won’t take much of your time or effort.

    Examples of monitoring and maintenance activities for DIY solar are:

    Dusting and washing your solar panels when they’re dirty.

    Checking the tightness of all screws, bolts, and connections and tightening any loose items. This should be done regularly.

    Dusting and cleaning the environment of your inverter(s), batteries, etc. at least twice a month.

    Frequently check if the cables and components are operating at their optimal temperatures.

    Failure to follow all maintenance guidelines might damage your solar system, pose health risks to you, or void your warranty.

    We highly recommend you bring any faulty Renogy equipment to us or a licensed professional for repairs. Attempting any DIY repairs is often a recipe for disaster, voiding warranties, or causing further damage.

    Related articles:

    How to Properly Size a PV System

    How Much Are Solar Panels? | 2023 Guide UK

    Average Solar Panel Output Per Day: UK Guide

    Solar Panel Incentives And Rebates In The Uk

    What Are The Most Efficient Solar Panels?

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    DIY Solar Power Installation

    Updated June 22, 2022 Solar

    Solar installation has become easier over the years. With the steady advancement of solar technology, installing solar panels and photovoltaic system equipment will surely get even more simplified in the future.

    However, that does not mean that solar installation is an easy 5 step process or that everybody should try it.

    Solar Installation: What You Should Know Before You Start

    Since solar installation involves working with panels and equipment that produce several hundred volts of electricity in the sunlight, some very serious safety issues must be understood before you consider installing solar panels or PV system components onto your home.

    Often, the work involved in solar installation needs to be done by a professional, permits need to be applied for and specific electrical standards (which often differ from one area to the next) have to be met.

    It is for this reason that there is also often a lot of improvisation involved when installing a solar power system.

    Although we do not in any way encourage you to disobey the standards, rules, requirements, and guidelines set forth by your municipality in regards to how to install solar panels or a solar energy system, we do show you some ways of working around some of the harder aspects of solar installation at the end of this web page. To be sure, check with your local building and safety department for specific requirements.

    Let’s take a look at the basic procedure for installing a grid-tied solar power system in your house.

    Installing Solar Panels Solar Energy Systems

    First you must make sure that your roof or wherever you’re going to be mounting your solar panels is strong enough for solar panel installation and to support the weight. There’s no point in installing solar panels on a roof that is going to cave in and ultimately cost you more money to repair.

    Unless you’re using solar roof tiles, the next thing you must do in the process of solar panel installation is measure the dimensions of your roof and ensure that your solar panels (the entire solar array) can fit in the available space.

    solar, panels, guide, flat, roof

    When installing solar panels, you may also want to consider using an area where there is considerable space for the addition of more panels in the future. For proper solar panel installation, ideally, solar panels should go on a rooftop that faces the direction that the sun comes up from.

    So, if in your area the sun rises in the east, your panels should face east for maximum exposure. Just make sure the roof has no shade on it from other homes, buildings, trees, etc.

    One important thing you must know about solar panel installation is that having just one solar panel in the shade can stop your whole solar array from working properly. Also, when you are installing solar panels, make sure that shade won’t come with the changing of the seasons or with the future development in your neighborhood. Install solar panels no closer than 12 from the edge of the roof and 16 from the eaves.

    Before you install solar panels, you must install brackets on sloped roofs or mount rails on flat roofs. Solar panel mounts can be bought in home improvement or solar stores. Standoffs for the brackets or rails must be secured to the home’s rafters or trusses, not just the sheathing.

    Solar installation brackets are used on roofs that are sloped, but the slope must be positioned in a way that gives the panel good direct exposure to the sun. A mount rail system is used in solar installation to allow you to position the panel at any angle you want. You must keep all the solar panels at the same angle and height (even when the roof slope changes) to keep the voltage production the same.

    Make sure you use roof sealant where you drill the screws into the roof when attaching the brackets or mount rails. so no rainwater can leak through the holes in your roof. Follow the instructions that come with the brackets or rail system you use to ensure that your solar panel installation is done according to manufacturer’s recommendations.

    Then attach your solar panels by hoisting them up to your roof, laying them out onto the brackets or mount rail system, and fastening them onto the bracket or rail system. When installing solar panels make sure they don’t accidentally slide off of very sloped roofs before you get a chance to secure them.

    When solar panel installation is complete and your panels are secure you must connect them according to how you want them to produce power. Make sure all your wires are properly insulated and waterproof (wrapped with black electrical tape). To prevent shock, always connect a ground wire from the mounting hardware to the earth when performing a solar installation.

    Once the panels have been connected and aligned in place, the conduit must be run underneath the panels, to a junction box, down the side of the house, and the first photovoltaic component in your system. usually the DC disconnect.

    For solar power installation, you must use wiring consisting of three wires: negative, positive, and ground wire. None of the wiring should be touching the actual roof.

    Installing conduit over all wires coming out of your panels is essential to protect them from exposure to rain, sunlight, and other elements.

    Now set up all of your photovoltaic components according to the manufacturer’s instructions (but don’t connect them yet). Install your inverter and the other photovoltaic components in a garage or an outbuilding. Make sure that the area is dry, well ventilated, and that the space is not subject to extreme hot or cold temperatures. This is especially important when it comes to your battery bank.

    If there’s going to be any cold weather at all, you should use a battery box around your entire battery bank to protect it from changing environments. A battery box is also necessary to protect children and pets from accidental electrical shock.

    The next step in a typical PV installation would involve running the power from your inverter into your home’s AC breaker panel and other system components. To do this, first, turn off the main breaker and de-energize all AC and DC sources of power.

    Then, connect your inverter to your AC breaker panel. Connect the PV wires to the DC disconnect switch and the other photovoltaic system components up until the main DC disconnect. Then connect the main DC disconnect to the inverter.

    After you do this, (and ensure that your system is safe by getting a professional electrician to test and verify that everything is working properly), you can turn on your breakers and DC/AC disconnect switches and electricity will be distributed from the AC breaker panel to any electrical loads in your home.

    When wiring through walls, use conduit to protect against shock and short circuits. For outdoor wiring, use PV conduit over the wires, with waterproof fittings or duct seal to keep out water.

    Also anytime, you’re going to be sharing solar power with power from your electric company, it’s a good idea to install a second smaller panel box beside your main one for the solar feed, along with a convenient shut-off switch to make cutting the power from the solar panel easy if necessary. A very common and usually required safety procedure in solar installation.

    The breaker that is used for the solar feed must not exceed 20% of the AC breaker panel’s service size. So if your home’s electrical service is 100 amps, this limits your breaker size to 20 amps. If you install solar panels and a PV system that has more amps than that, you may need to increase your home’s electrical service to 200 amp or higher.

    Solar Installation Shortcuts

    Here we list a few alternative ways you can save even more money (and work) by simply working around some of the more expensive and legally complicated aspects of solar energy installation.

    Roof or Yard?

    If solar panel installation is a little too labor-intensive for you and you don’t want to go through all the trouble of mounting and installing solar panels on your roof, you can always place them in your backyard or on your balcony. This will require your panels to have some kind of a stand or adjustable support behind them.

    However, different areas have different rules for this as well. Some areas require that any solar panels not mounted to the roof must be protected from the general public via the use of fencing or a pole mount 8 feet or higher. Do your homework and find out what’s required in your area before proceeding.

    Panel or Plugs?

    If you don’t want to connect directly to your home’s AC breaker panel, you can plug appliances directly into the inverter. Just set up a system where you plug appliances, TVs, toasters, lights, etc, into a convenient box of direct access power outlets (plugs).

    This can be as easy as attaching an extension cord from the power inverter, passing it into the house, and adding a power bar with multiple easy access outlets. Many people choose to implement little solar installation shortcuts like these to work around’ some tough spots.

    With these options to work around some of the more expensive (and complicated) aspects of solar power installation, it gets even easier for you to create a system that can recover more of your initial costs within just months instead of taking years.

    How to Mount Solar Panels

    Solar panel arrays can be mounted in many ways, so it’s important to understand considerations like materials, costs, and orientation before deciding on a mounting system.

    As solar panels for homes and businesses become increasingly popular, more and more people learn about the solar installation process. But even though it’s relatively simple to find information about solar panel reviews, leading manufacturers, and even installers in your area, it can be challenging to locate details about certain highly specific (but necessary) topics – such as how to mount solar panels.

    There are various methods for mounting solar panels, which we will walk you through in this handy guide. You’ll learn:

    • What is solar panel mounting and racking?
    • What are the components of a solar panel mounting system?
    • How do you choose the best solar mounts for roof and ground installation?
    • How much do solar panel mounts cost?
    • Where do you buy solar panel mounts?

    With this resource in hand, you’ll be well-equipped to choose the best solar panel mounts for your project.

    What is Solar Panel Mounting and Racking?

    Solar panel mounts and racks are specialized equipment systems used to install solar panel arrays in a secure, stable position. Solar panel arrays can be mounted in many ways: on building roofs, on poles in the ground, and even with tracking. A mounting system can also help optimize your solar panels’ location and position, maximizing sun exposure and overall performance and efficiency.

    Ultimately, the objective is a solidly mounted solar panel array that will last for many years and withstand extreme weather. Several manufacturers make stationary solar panel mounting structures designed to work with almost any solar panel model. This hardware is intended for multiple applications and different mounting techniques, and considerations like wind and snow loads have been included in their design. Using fixed, stationary mounting hardware is the simplest and often the most cost-effective way to mount solar panels. Customized or sun-tracking array mounting structures can be expensive but could be ideal if you are dealing with a unique scenario.

    No matter what mounting option you choose, it is crucial that all racking and mounting products meet the guidelines for durability and structural integrity. Settling for a flawed system can put you at risk of experiencing damage to your solar system during high winds or weather events – and the last thing you want is to sacrifice your investment – and potentially your source of electricity – just to save a few bucks on the mount.

    Solar Panel Mounting Components

    Three main components make up a solar mounting system:

    Each of these serves an essential role in supporting and stabilizing your panels.

    Roof Attachments

    The roof attachments are specialized fasteners drilled into the roof that allow for the secure attachment of the mounting rails. Your roof type determines your roof attachment options. For example, composite shingle roof attachments must include flashing (plastic or metal) to prevent leaks, while standing metal seam roof attachments utilize a clamp design.

    Mounting Rails

    The mounting rails connect to the drilled-in roof attachments. These rails are what hold and support your solar panels. Solar panel mounting rails come in different thicknesses and lengths. Thicker rails are stronger and can support more weight and distance between roof attachments (known as “spans”). Thin rails like the IronRidge XR10 should not be used in climates where snow can accumulate on your solar panel array due to the added weight, whereas the IronRidge XR1000 can handle heavy snow loads.

    There are options for racking with no rails (most notably mounting your solar panels on poles), but rails are the most common choice simply because they are exceptionally versatile and easy to work with. You can set up solar panels on many different roof angles with mounting rails.

    Module Clamps

    The module clamps fasten the solar panels (solar modules) to the mounting rails. Your module clamp options are determined by your mounting rails, not by your solar panels. Most module clamps available today are adjustable to be compatible with all standard solar panels.

    A Note on Electrical Grounding

    The National Electric Code (NEC) requires that all solar power system equipment be electrically bonded and grounded to the earth. Doing so keeps both the system and people in its vicinity safe should lightning or any other electrical current pass through it unexpectedly. Most solar panel racking and mounting systems have a solution for this by virtue of their required components or materials used. Still, it bears repeating: make sure your system is electrically bonded and grounded.

    Where to Buy Solar Panel Mounts

    You can find solar panel mounting systems for sale through direct distributors, like altE. We partner with manufacturers to give our customers access to industry-leading products, so you can eliminate the extra costs and hassle of buying through a solar installation company.

    Expect to buy the individual components for mounting solar panels because there usually aren’t fully-constructed mounting systems available. This is because it would be challenging for manufacturers to create system designs that suit all possible roof sizes, slopes, and styles, not to mention ones sized for the specific number of solar panels in your system’s array(s). That said, roof mounting kits from Tamarack Solar are available for smaller arrays of 4 or 8 panels. These kits include all mounting and racking components needed except for flashing, which you can easily purchase separately.

    How Much Does it Cost to Mount Solar Panels?

    The price of a solar mounting system varies based on factors such as:

    • The type of racking
    • How much equipment you need
    • Installation method (labor costs for professional vs. DIY)

    A good rule of thumb is to plan to spend about 10% of the total cost of the solar energy system on mounting. For example, if your new solar energy system costs about 10,000, your mounting system would equate to about 1,000 of that total.

    Selecting the Best Solar Mounts for Your Project

    When shopping around for solar mounts for sale online, it’s easy to be overwhelmed by all the available options. But with an organized approach, you can make an informed choice that serves your needs.

    Your budget, location, and other factors can significantly impact which mounting material is suitable for you. Let’s consider the characteristics of various mounting materials:

    • Aluminum – lightweight, strong, and resistant to corrosion. Aluminum angle is easy to work with, you can drill holes into it with commonly available tools, and the material is compatible with most solar panel frames. Aluminum is not easy to weld.
    • Angle Iron – easy to work with but corrodes rapidly. Galvanizing will slow corrosion, but mounting brackets and bolts will still rust, particularly in a wet environment. The material is readily available, and brackets can be welded easily.
    • Stainless Steel – Expensive and difficult to work with but will last for decades. This may be a good investment in salt spray environments.
    • Wood – Inexpensive, available, and easy to work with but may not withstand the weather for many years – even if treated with preservatives. Attaching modules to a wooden frame requires battens or clips to hold them.

    Roof-Mounted Solar Panels vs. Ground-Mounted Solar Panels

    There’s no question that roof-mounted solar panels are the most common in most areas. Because setting up solar panels on a roof often allows maximum sunlight exposure and doesn’t take up extra space on the property, many home and business owners prefer this method.

    However, roof mounting solar panels is generally more complex than either ground mounting or pole mounting. Roof mounts are more challenging to install, mainly if the roof orientation and/or angle are not good for solar (for instance, north-facing or flat roofs).

    Home and business owners that choose ground-mounted solar panels typically do so for one of four key reasons:

    • They don’t have enough roof space for a roof-mounted system
    • Their roof is north-facing or is shaded by trees or nearby structures, which is not ideal for solar panel output
    • The ground allows for better optimization of the system
    • They are using bi-facial solar panels

    Roof mounting should also be avoided when the roof is nearing the end of its expected life (typically 20 years for a composite shingle roof). Disconnecting and removing the solar panels, racking, and mounting to get the roof replaced adds a lot of cost and complexity to the job – as does reinstalling all the solar equipment after the roof has been replaced. Keep in mind that roof-mounted solar panels extend the roof’s life beneath them by protecting them from the elements – so you don’t need a new roof if you want to roof-mount your solar panels, but you shouldn’t have an old one either.

    Ground-mounted solar systems can be secured directly into the ground or attached to ballasted mounts. Ballasted solar mounts are freestanding, held down by the weight of the panels (and sometimes additional weight as well) but not secured in the ground. Since there isn’t any drilling required for ballasted solar mounts, this type is popular for ground-mounted systems.

    There isn’t necessarily a right or wrong answer in the debate of roof vs. ground solar installation – it all comes down to the approach that works best for your project needs and goals.

    Tips for Professional and DIY Solar Mount Installation

    Depending on your skill and comfort level with home improvement projects and the specifics of your project, you might be weighing your options between professional or DIY solar installation. Whether you opt to hire a professional or install your mounting system yourself, here are a few tips to keep in mind:

    • The foundation for the array should be designed to meet the wind and snow load requirements of the region. Wind load depends on the size of the array and the tilt angle. Ask a local contractor how to anchor your array to withstand the wind and snow expected in your area.
    • Regardless of whether you buy or build the mounting structure, make sure it is anchored, and the modules are restrained.
    • If roof mounting, allow a clear airflow path up the roof under the array. The array will operate cooler and produce more energy if it stands at least 3 inches off the roof.
    • Penetrating the roof seal is inevitable – use flashing properly to avoid leaks.
    • It is essential to secure your roof attachments firmly. Attaching them to the rafters will provide the best foundation, but this may be difficult because module size and rafter spacing are usually not perfectly compatible. If there is access to the underside of the roof, insert 2 x 6-inch blocks between the rafters and the attachment made to the blocks.
    • Attaching the array to the roof’s plywood sheathing may result in roof damage, particularly if high winds are likely.

    Shop Solar Mounting Parts for Sale Online Now

    Are you interested in saving money and completing a solar project that meets your expectations? When you shop with altE, you can get all of the equipment you need to tackle a DIY solar installation – or you can buy the components and then hire a professional installer. Whichever option you choose, the cost is typically far less than what you would pay to hire a solar company to complete the process.

    altE carries solar mounts and other equipment from the industry’s best, most innovative brands, selecting and stocking only the highest-quality items. Our customers know that they are investing in products and equipment that will last, making the most of their solar solution in the short and long term.

    If you still have questions about which solar mounting system to buy, the altE team is happy to help. Contact us for more information or start shopping now!

    Installing Solar Panels on a Flat Roof (3 Tips to Optimize Output)

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    Written by Dan Simms

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    The optimal angle for solar panels in North America is between 20 and 45 degrees toward true south, usually depending on your latitude. However, solar panels can still be a worthwhile investment even if you have a totally flat roof.

    solar, panels, guide, flat, roof

    In this article, we’ll discuss how efficient panels can be on flat roofs, the cost of a flat roof solar panel system and more. We’ll also offer four tips for saving money upfront and over time on your flat roof solar array.

    Can You Install Solar Panels on a Flat Roof?

    Yes, you can usually install photovoltaic (PV) panels on a flat roof, although the installation does come with some challenges that might make it impractical.

    Most importantly, solar panels generate the most electricity for your home when they receive direct sunlight. The more direct the sunlight is when it hits the face of the panel, the more power it will generate in all conditions. Of course, a higher level of production translates to greater energy savings over time.

    solar, panels, guide, flat, roof

    It’s not entirely clear what kind of power production differential you’ll see between flat and angled panels, although most estimates suggest between 30% and 50% less energy from flat panels.

    Even considering the reduced energy production of flat panels, installing a solar energy system on a flat roof can still be beneficial and, in some cases, save you even more money than going solar with a standard angled roof. We’ll discuss how in greater depth later on.

    For now, the table below should illustrate how much of a difference you might see in solar production based on the angle at which your panels are installed. Since the optimal panel angle is based on your latitude, the table assumes you’re located at around 40 degrees N, which is about the center of the United States.

    Panel Angle Expected Power Loss Compared to Optimal Angle
    45 degrees 26.25%
    40 degrees (about optimal at 40 degrees N latitude) 0% (optimal)
    35 degrees 26.25%
    20 degrees 15%
    0 degrees (flat) 30%
    -40 degrees (North-facing panels) ~50-80%

    Blue Raven Solar

    Benefits of Installing Your Solar Panel System on a Flat Roof

    As mentioned above, there are some benefits to installing panels on a flat roof as opposed to one that’s angled. You could pay less for a flat-roof system, and you could run into fewer restrictions with respect to the orientation of your panels. We’ll explain each of the benefits of a flat-roof installation below.

    • Potentially lower installation cost: Flat-roof systems can sometimes cost less than angled-roof systems, depending on the type of racking equipment used for the installation. Ballasted racks—which we’ll discuss in greater depth later—can sometimes be more affordable than a typical mounting system. Plus, the installation on flat roofs is inherently safer and could end up being cheaper due to a faster installation time and no need for safety equipment.
    • Potential for larger system: With an angled roof, you lose about 50% of your roof space if your home faces north or south, as one half is angled away from the sun and typically isn’t viable for solar panel placement. With a flat roof, you don’t run into this issue, so you could potentially be able to fit a much larger system on your roof. This could mean greater savings for your home or place of work, especially if you have an energy consumption rate that is above average.
    • Potential for longer system life: Solar panels on slanted roofs have quite a long lifespan in most cases, with equipment warranties averaging around 25 years and some panels lasting upwards of 30 years. Continuous changes in temperatures—especially at the extremes—can put added wear on the electronics inside your PV panels. Flat panels receive less direct sunlight, thereby seeing less drastic temperature changes and potentially lasting even longer than those installed at angles that are ideal for maximizing production.
    • Panels won’t get as hot: As mentioned above, flat panels won’t typically get as hot as those installed at an angle toward the sun. This could increase their lifespan, but it also minimizes the reduction in efficiency from the inopportune angle. High temperatures can reduce efficiency by up to 25%. While the intensity of sunlight hitting flat panels will be lower, efficiency loss to heat will also be reduced, meaning flat panels are only slightly less efficient in some cases than those installed at an angle.
    • Installation can be done without roof penetrations: Traditional angled roofs require roof shingle penetrations to install the racking system, and this naturally increases the risk of roof leaks. Flat-roof PV systems can be installed using penetrations as well, but they can also use a ballasted mounting system, which uses weights to keep the system in place. This keeps the risk of roof leaks low, which is great since flat roofs are naturally more prone to leaking.
    • No concern for property orientation: Finally, if you have a pitched roof, you’ll be limited in the direction your panels can face. If your roof slopes are angled to the east and/or west, your production is naturally going to be lower than if your roof slope faces south. If you only have a slope facing to the north, you’re in an even less beneficial position. With a flat roof, it doesn’t matter which direction your home faces because you can always install angled mounts to direct the panels to the south.

    Challenges of Installing Your Solar Panel System on a Flat Roof

    Of course, there are some challenges that will need to be considered when it comes to a flat-roof solar installation. We’ll discuss each of the potential complications of installing solar on a flat roof below.

    • Production will be lower: First, as mentioned above, flat panels don’t get the same sunlight intensity, which means production is lower. This could be an issue if you’re looking to keep installation costs down but still maximize power production.
    • Panels naturally get dirtier, reducing efficiency: Angled panels are considered “self cleaning” because they naturally get washed every time it rains. The angle allows the water to flow off of them, clearing off dirt, pollen and other debris. Flat panels see a much higher concentration of debris because they don’t get washed naturally. Over time, that build-up will reduce production and, in turn, your energy savings. You’ll either have to wash the panels yourself or pay for ongoing panel maintenance to maintain the highest level of efficiency possible.
    • Flat panels are more prone to water damage: If your panels are mounted parallel to your flat roof, water will naturally pool on top of them, and they’ll more easily collect and hold snow in the winter. This leaves them more prone to water damage, which can reduce panel lifespan in some cases. In fact, many manufacturers will waive the 25-year equipment warranty they normally provide if panels are installed flat.
    • Fewer solar contractors available: Finally, while most homeowners have access to tons of solar installers that can install panels on an angled roof, there are far fewer solar installation companies that specialize in flat roof applications. We recommend going with a company that has experience installing on flat roofs, especially given the nuances and potential downsides we’ve mentioned above. In some areas, you may not be able to find any providers that can or are willing to install a flat-roof solar array.
    • Higher chance of shading: While any roof can be shaded from sunlight from trees or nearby buildings, flat roofs come with some additional obstacles that can cast shade. These include parapet walls, roof vents, HVAC equipment and more. Panels should be installed away from parapet walls and other protrusions to prevent shading during sunlight hours.

    Will You Need Special Equipment for a Flat Roof Solar Panel Installation?

    Solar installations on flat roofs can be done using three different racking systems: a traditional rack that gets mounted to the roof using penetrations, an angled rack that uses the same method and a ballasted rack that gets held in place using weights.

    The mounted rack that holds your panels parallel to your roof won’t provide the greatest efficiency due to the angle of your panels with respect to the sun, but it is the most affordable option. The cost is typically a little less than a traditional installation on an angled roof because the roof is more accessible, and the installation crew often won’t need to maneuver safety equipment around, which can speed up the work.

    The angled rack is also similar to what an installer would use on a sloped roof, but it includes additional braces to hold your panels up at an angle. This solar panel mounting system design isn’t unlike what you’d see on a ground-mounted solar array. It’s just as easy to install, but it’s a little more expensive, as the materials cost more.

    The ballasted mounting system holds your panels at an angle as well and relies on gravity to keep the array in place. This option may not be realistic in areas that see extreme winds—like during hurricanes or tropical storms—and may require seismic anchors in areas where earthquakes could put the system at risk of shifting off the roof. Ballasted mounting systems are the most expensive of the flat roof mounting options.

    The table below includes a quick breakdown of all of the equipment you need or could opt for in flat and sloped roof applications.

    Equipment Flat Roof Sloped Roof
    Solar Panels Required Required
    Angled Roof Mount Optional (recommended for maximizing solar production) N/A
    Backup battery storage Optional (recommended in areas with frequent blackouts or no access to net metering) Optional (recommended in areas with frequent blackouts or no access to net metering)
    Inverter Required Required
    Wiring Required Required
    Squirrel Bird Guards Optional (strongly recommended for flat-mounted panels close to the roof) Optional (strongly recommended)

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