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Will I need solar Photovoltaic panels to pass the New Part L 2021 SAP calculation?

With more and more emphasis being placed on sustainability, it’s a question on the minds of many architects and builders as it’s crucial when designing and constructing buildings that are as efficient as possible.  Unfortunately, the answer, is not a straightforward one. In the past, it has been possible to achieve building regulations compliance by using by using less efficient measures, with Photovoltaic panels (PV) only being required to achieve an EPC rating of A. However under the new regulations this is due to change.


In this blog post, we’ll explore the factors that determine whether or not PV panels are necessary. So read on – you may just learn something new!


What is Standard Assessment Procedure (SAP)?


SAP is a set of procedures used to calculate the carbon emissions (known as the DER) and energy performance of a building. The calculation results in a building regulations compliance report and an Energy Performance Certificate (EPC), which shows how energy efficient a building is and what improvements could be made. Without an EPC, it can be difficult to sell or rent a property or even find a mortgage for your property. So, if you’re planning on building, renovating or designing a property, make sure you understand Standard Assessment Procedure and how it can benefit you!


How photovoltaic panel will help you pass the SAP calculation 


If you’re looking for a way to pass the SAP calculation with flying colours, then you should consider installing PV panels. PV panels have many benefits that make them an ideal choice for those looking to improve their energy efficiency.


For one, PV panels are efficient at converting sunlight into electricity. In fact, they are becoming more efficient all the time with improving performance specifications.


With the increasing cost of electricity tariffs, installing PV will help to reduce your electricity bill.


Additionally, PV panels require little maintenance, making them an extremely low-maintenance option for those who want to save on energy costs.


Finally, the cost of installing PV panels is reducing all the time, making them a good option for reducing energy bills and helping to comply with building regulations.


Factors that determine whether or not PV panels are necessary


The benefits of having a photovoltaic panel are clear. They provide renewable energy, they reduce your carbon footprint, and they can save you money on your energy bill. However, there are a few factors that determine whether or not PV panels are necessary to pass the SAP calculation.


Under the old Part L 2013 regulations, solar PV panels were not required and if a development was built to a good standard of fabric efficiency, then this alone would help to pass the SAP calculation.


However, under the new Part L 2021 and SAP 10, PV is now in the new building regulations for the notional assessment. This means that when assessing a dwelling, it will be compared with having solar PV and therefore, if PV is not installed, it will be very difficult to pass the SAP assessment.



Although, this based on using a gas boiler. If you were to install an electric Air Source Heat Pump or Ground Source Heat Pump, then it will be much easier to pass the SAP assessment and there would be no need to install PV! This is due to the high efficiency of the heat pump system.



Will PV work for me? 


If using gas or standard electric heating, we know it is likely that PV will be needed but there are several design factors to check when reviewing the feasibility of PV.


First is the size of your property. If you have a large property, you may need more PV to meet the requirements.


Second, is the dwellings roof layout. For example, does it have roof lights or dormers? If so, PV may not work as a dwelling’s design needs to consider space for PV.


The third factor is the orientation. Does the dwelling face in the right direction? South facing pitched roofs are the optimum orientation for PV on the roof. Flat roofs can also work too with PV located horizontally or on a slight angle. It is also worth checking if the dwelling will be overshadowed by any neighbouring properties or trees.



How Base Energy can help


Whether you’re just starting out on your building journey or are a little further down the line, our consultants are more than happy to help with any questions or queries you may have.  Base Energy is here to guide you through the process and offer a seamless transition that will help you meet compliance regulations as quickly and easily as possible. Contact us today to get started on your Standard Assessment Procedure calculation- it’s easier than you think!


SAP Calculation



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