Your Energy Questions, Answered
Whether you are a homeowner exploring solar for the first time, a developer navigating compliance requirements or an architect looking for a reliable installation partner, we have put together straightforward answers to the questions we get asked most. Browse by audience below or scroll through to find what you need.
FAQs For Property Developers
What is a SAP calculation and do I need one for a new build?
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SAP stands for Standard Assessment Procedure. It is the UK government's method for assessing the energy performance of new homes. A SAP calculation is required for all new residential buildings to demonstrate compliance with Part L of the Building Regulations, which sets minimum standards for energy efficiency. You will need a SAP calculation at design stage to support your planning application and again at completion to produce the as-built EPC. Flint Energy provides SAP calculations for new build developments of all sizes.
What EPC rating do new build homes need to achieve?
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New build homes are currently required to achieve a minimum EPC rating of B under Part L of the Building Regulations. In practice, many developers aim for an A rating, particularly on schemes where sustainability credentials are a selling point or where planning authorities have set higher targets. Flint Energy works with developers from early design stage to ensure the right systems are specified to hit the target rating first time.
What does Part L compliance mean for residential developments?
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Part L of the Building Regulations sets the standards for the energy efficiency of new and existing buildings in England. For new residential developments, Part L (Conservation of Fuel and Power) requires developers to demonstrate that the building meets minimum fabric energy efficiency standards and that primary energy use and carbon emissions are within set limits. Meeting Part L requires accurate SAP calculations, correctly specified systems and proper commissioning and testing at completion.
How early should I appoint an energy consultant on a new development?
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As early as possible — ideally at concept or pre-planning stage. Appointing an energy consultant early means your energy strategy is built into the design from the outset, rather than being retrofitted to meet compliance requirements at the end. Early involvement reduces the risk of costly redesigns, helps inform planning submissions and ensures the right technologies are specified correctly. Flint Energy engages with developers at all stages, but early appointment delivers the best outcomes.
Can solar PV help my development meet planning requirements?
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Yes. Solar PV is one of the most effective technologies for meeting the energy efficiency and carbon reduction requirements that planning authorities increasingly attach to new residential and commercial developments. In many cases, solar PV combined with battery storage or heat pumps is the most cost-effective route to achieving the required EPC ratings and carbon targets. Flint Energy provides energy modelling to demonstrate compliance at planning stage.
What is the difference between a predicted and an as-built EPC?
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A predicted EPC is produced at design stage, based on the specifications of the building as planned. It is used to support planning applications and demonstrate compliance with Part L. An as-built EPC is produced after construction is complete, based on the building as it has actually been built and the systems as they have been installed and commissioned. Both are required for new build residential developments. Flint Energy produces both as part of our end-to-end compliance service.
Meeting Net Zero on a residential development typically requires a combination of high fabric performance (insulation, air tightness), low-carbon heating (heat pumps), renewable energy generation (solar PV) and energy storage (battery). The right combination depends on the building type, location and target EPC rating. Flint Energy provides Net Zero planning support from early feasibility through to installation and certification.
How do I meet Net Zero requirements on a residential development?
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FAQs For Architects & Consultants
How do I integrate solar PV into a building design without affecting aesthetics?
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Solar PV technology has developed significantly in recent years and there are now options to suit almost any architectural brief. Building-integrated photovoltaics (BIPV) can replace conventional roofing or cladding materials entirely. In-roof systems sit flush with the roof surface rather than sitting on top of it. For flat roofs, panels can be positioned at low angles or set back from the parapet to minimise visual impact. Flint Energy works with architects from early design stage to find solutions that meet both technical and aesthetic requirements.
What is Part O and how does it affect residential design?
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Part O of the Building Regulations, introduced in 2022, sets requirements for limiting unwanted solar gains in residential buildings to reduce the risk of overheating. It applies to new residential buildings in England and requires designers to demonstrate that the building will not overheat in summer conditions. Part O assessments need to be carried out at design stage and can influence decisions about window sizing, orientation, shading and glazing specification. Flint Energy provides Part O compliance assessments as part of our design-stage consultancy.
Who is responsible for SAP calculations on a new build project?
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SAP calculations are typically commissioned by the developer or main contractor, but the responsibility for ensuring they are carried out correctly sits with the project team as a whole. Architects and consultants play a key role in providing accurate design information for the SAP assessor to work from. Where Flint Energy is engaged as the energy consultant, we work directly with the design team to ensure the information we need is available at the right time and that the SAP calculations accurately reflect the design intent.
Can solar panels be specified on any roof type or orientation?
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Solar panels can be installed on most roof types, including pitched, flat, mono-pitch and mansard roofs. South-facing roofs at a pitch of around 30 to 40 degrees deliver the best performance, but east and west-facing installations are increasingly common and can still deliver strong returns. North-facing roofs are generally not suitable. Shading from nearby buildings, trees or roof features should be assessed at design stage to avoid performance losses. Flint Energy carries out shading analysis and production modelling as part of our system design process.
What accreditations should an energy installer hold?
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For solar PV and battery storage, look for MCS (Microgeneration Certification Scheme) accreditation, which is required for installations to qualify for government incentives including the Smart Export Guarantee. For heat pumps, MCS accreditation is also required for Boiler Upgrade Scheme eligibility. NAPIT and NICEIC are recognised electrical accreditation bodies. RECC (Renewable Energy Consumer Code) provides additional consumer protection standards. Flint Energy holds accreditations across all relevant schemes including MCS, NAPIT, RECC and TrustMark.
FAQs For Homeowners & Landlords
How much do solar panels cost and how long is the payback period?
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The cost of a domestic solar PV system in the UK typically ranges from £5,000 to £13,000 depending on the size of the system and the property. Most households see a payback period of between 8 and 12 years, though this varies depending on energy usage, tariff rates, the amount of solar generation exported to the grid and whether battery storage is included. With energy prices remaining high, many homeowners are seeing payback periods at the shorter end of that range. Flint Energy provides detailed savings projections as part of our free home energy assessment.
What is the Smart Export Guarantee and how does it work?
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The Smart Export Guarantee (SEG) is a UK government scheme that requires licensed energy suppliers to pay households for surplus electricity they generate through renewable sources and export back to the national grid. If your solar panels generate more electricity than you use, the excess is exported and you are paid a rate per kilowatt hour by your energy supplier. SEG rates vary between suppliers, so it is worth comparing tariffs. To qualify, your installation must be MCS certified. Flint Energy installs to MCS standards as standard
What is the Boiler Upgrade Scheme and am I eligible?
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The Boiler Upgrade Scheme (BUS) is a UK government grant that provides £7,500 towards the cost of installing an air source heat pump, and £7,500 towards a ground source heat pump, for homeowners in England and Wales replacing an existing fossil fuel heating system. To be eligible, your property must have a valid EPC with no outstanding recommendations for loft or cavity wall insulation. The grant is paid directly to the installer and deducted from the cost you pay. Flint Energy is an accredited heat pump installer and can advise on eligibility and the application process.
Can I get a grant for a heat pump in the UK?
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Yes. The main grant available is the Boiler Upgrade Scheme, which provides £7,500 towards the cost of an air source or ground source heat pump for eligible homeowners in England and Wales. The Governments’s ECO4 scheme may also provide funding for heat pumps in properties occupied by low-income households or those on certain benefits. Flint Energy can assess your eligibility for available funding as part of a free home energy assessment.
What EPC rating do I need to rent out my property?
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Rental properties in England and Wales currently require a minimum EPC rating of E to be legally let. The government has proposed raising this minimum to C for new tenancies, though the timeline for this change has not yet been confirmed. Landlords who act now to improve their properties to EPC C or above will be better positioned for future regulation changes and are likely to see lower void periods as tenants increasingly prioritise energy-efficient homes. Flint Energy provides EPC assessments and improvement planning for landlords.
Can solar panels be installed on a flat roof?
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Yes. Flat roof solar installations use angled mounting frames to tilt the panels to the optimum angle for solar generation, typically between 10 and 30 degrees. Flat roof installations are common on commercial and residential buildings and can deliver strong performance. The structural loading of the roof needs to be assessed before installation. Flint Energy carries out site surveys and structural assessments as part of the design process.
A solar battery stores the electricity your solar panels generate during the day so you can use it in the evening, when your panels are no longer generating. Without a battery, surplus solar generation is exported to the grid, often at a lower rate than you pay to import electricity. With a battery, you can use more of the energy you generate yourself, reducing your bills further. Whether a battery is worth it depends on your energy usage patterns and the size of your solar system. Flint Energy models the projected savings with and without battery storage as part of our system design process.
What is battery storage and is it worth it with solar panels?
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A standard domestic solar panel installation typically takes one to two days. Larger or more complex installations may take longer. The process involves mounting the panels on the roof, installing the inverter and wiring inside the property, connecting to the consumer unit and completing the necessary safety checks and certification. Flint Energy manages the full process including any applications to your network operator and MCS certification..
How long does solar panel installation take?
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In most cases, no. Solar panels on domestic properties in England are covered by permitted development rights, meaning planning permission is not required as long as the installation meets certain conditions — for example, panels should not protrude more than 200mm from the roof surface and should not be installed on a wall facing a highway. Properties in conservation areas, national parks or Areas of Outstanding Natural Beauty, and listed buildings, may have additional restrictions. Flint Energy can advise on whether planning permission is required for your property before any work begins.
Do I need planning permission for solar panels?
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ECO4 is a UK government scheme that funds energy efficiency improvements for low-income households in properties with poor EPC ratings, delivered through energy suppliers. It can cover insulation, heat pumps, solar panels and other energy efficiency measures at no cost to eligible households. Eligibility is based on household income, benefit status and the property's current EPC rating.
The current ECO4 scheme runs to March 2026, after which the government is expected to reassess funding arrangements. If you think you may be eligible, it is worth acting sooner rather than later. Flint Energy can assess whether your property qualifies as part of an initial survey.