If your house needs a roof renovation, that’s the best moment for a solar system. Planning solar panels and the roof renovation together means the scaffolding only goes up once, you avoid removing and refitting the modules later, and you meet the solar obligation that has applied to many roof renovations in Lower Saxony since 2025. Here you’ll learn what the law requires, which funding is available in the Hanover region and how to coordinate both projects sensibly.<\/p>\n
Planning a roof renovation and want to include solar from the start? Request your free, no-obligation quote now<\/a>.<\/p>\n A PV system stays on the roof for 25 years or more. If you install it on a roof that needs renovating in a few years, you’ll have to have the system removed and refitted later, which costs scaffolding, labour and yield. Conversely, it’s frustrating to open up a freshly renovated roof again for installation.<\/p>\n If you plan both together, the scaffolding goes up only once. The roof hooks can be fitted directly while the roof is being covered, and the cable routes are planned in at the same time. Your roofer carries out the roof renovation itself. We plan and install the PV system and coordinate the schedule with the roofer.<\/p>\n Since 1 January 2025, the solar obligation in the Lower Saxony Building Code (Section 32a NBauO) has applied not only to new buildings but also to existing buildings when the roof covering is fundamentally renewed. It applies to residential and non-residential buildings. The key points:<\/p>\n It’s best to clarify the exact exemptions and required evidence early with the building authority or your architect. Importantly, plan the PV system as part of the renovation from the start.<\/p>\n A 100 m\u00b2 gable roof is re-covered and insulated. After deducting 35%, 65 m\u00b2 remains, so the minimum area is 32.5 m\u00b2. If 50 m\u00b2 of modules are installed, 17.5 m\u00b2 are eligible, giving about \u20ac2,600. For insulating 100 m\u00b2, it would be \u20ac5,000, capped at 80% of the PV grant, i.e. about \u20ac2,100. Together, the Region contributes about \u20ac4,700 in this example, above the \u20ac4,000 minimum grant, plus the flat rate for electrical work on residential buildings.<\/p>\n You’ll find an overview of all programmes under solar funding in Hanover<\/a>.<\/p>\n On-roof systems<\/strong> are mounted above the new roof covering. They’re the standard solution: inexpensive, proven and well ventilated. During a renovation, the roof hooks can be fitted while the roof is being covered. We install using the K2 Systems mounting system.<\/p>\n In-roof systems<\/strong> replace part of the roof covering, with the modules sitting flush with the roof. They look more refined and can be an option for older or listed buildings. Which roof pitch and which roof covering are possible is specified by the manufacturer of the in-roof system. In-roof systems generally cost more per kWp than on-roof systems: for the in-roof system, we calculate approx. \u20ac250\u2013400 per kWp. During a renovation, the extra cost is somewhat lower, because the modules replace part of the roof covering. We install both: on-roof systems with the K2 Systems mounting system and in-roof systems with the GSE In-Roof System or the K2 In-Roof System, where the modules replace part of the roof covering. We check whether in-roof suits your roof during the on-site visit and coordinate the work with your roofer. Systems, prices and the installation process are explained in detail in our guide to in-roof solar panels: costs and systems<\/a>. Read more about mounting types under rooftop solar systems<\/a>.<\/p>\n As a guide, the PV system itself costs about \u20ac1,450\u20131,750 per kWp, so a 10 kWp system costs about \u20ac14,500\u201317,500 without a battery. Planning it together with the renovation also saves the cost of separate scaffolding and later removal. If an existing system has to be removed and refitted for a later renovation, providers quote from about \u20ac1,000, and considerably more depending on system size and scaffolding. In the Hanover region, the system produces about 893 kWh per kWp per year. Without a battery, a typical household uses 25\u201335% of the solar power itself, and 55\u201370% with a battery. Every self-consumed kilowatt-hour saves you grid electricity, which is 37 cents at an assumed price of 37 ct\/kWh. You’ll find an honest worked example under is solar worth it?<\/a><\/p>\nSolar Panels and Roof Renovation: Key Points at a Glance<\/h2>\n
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Why Solar Panels and a Roof Renovation Belong Together<\/h2>\n
PV Obligation for Roof Renovations in Lower Saxony<\/h2>\n
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Funding in the Hanover Region<\/h2>\n
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Worked Example: Region Funding for PV and Insulation<\/h3>\n
In-Roof or On-Roof?<\/h2>\n
What Does the Combination Deliver Financially?<\/h2>\n