Standard Assessment Procedures, or SAPs, are used to compile data for Energy Performance Certificates (EPCs), which are required for any new residential property.

Specifically, SAP calculations help define the design process of these developments, and they must pass certain criteria in order for Building Control to sign off on the development of any new residential property. Required by law since 1995, if a development fails to pass an SAP calculation, then it’s likely not able to be legally rented or sold.

In this post, we’ll take a closer look at Standard Assessment Procedures, what they aim to do and why they’re important. We’ll also cover why it’s important to engage an SAP assessor early in a property’s development so you ensure it will be able to pass an SAP calculation and comply with all of the necessary regulations. Here’s a closer look:

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SAP Calculations Explained

What are SAP calculations? SAP calculations are mandatory assessments for any and all new residential property developments. They may also be required for property conversions, and additions or extensions. Essentially, an SAP calculation is used to measure the energy efficiency of a property for the purpose of detailing an Energy Performance Certificate, or EPC. Based on the data in the EPC, Building Control will either approve or deny the property. In order to sell or rent a property, an EPC must be presented by law.

Why SAP Calculations Are Important

Simply put, SAP calculations are important for helping to define the energy efficiency and carbon footprint of a residential property. They’re designed to help improve the long-term sustainability of a property, reduce carbon output and contribute to the local and national goals that have been set for slowing the impact of climate change.

So, to answer the question: Why are SAP calculations important? They’re important for defining the energy performance of a new residential property and staying in check with sustainability goals. They’re also important to comply with set building regulations and to help inform the overall design process.

Who Needs SAP Calculations?

Any new residential development, any converted residential property, or any current residential property that’s being added on to or extended will require an SAP calculation.

The only exception with an extension or addition largely depends on how much glazing is incorporated. If it’s in excess of 25 percent of the area of the new extension, an SAP calculation is required. If it’s not, then you won’t need one.

The SAP Calculation Process

When Should an SAP be Performed?

Ideally, SAP calculations should be considered during the initial design stage of the development process and emphasised throughout to ensure the required regulations are met or exceeded.

For example, during the design phase of development, the SAP calculation will help dictate what materials should be used to meet requirements. However to answer the question of, “When should a SAP calculation be carried out?” The answer is before construction starts.

In fact, we suggest making sure your SAP calculations occur prior to the design state to eliminate the need for rework should alterations be made further along in the process.

After the property is constructed, you’ll need to carry out an as-built SAP calculation to craft the final EPC required by Building Control. The bottom line is that SAP assessments must be done multiple times throughout the development process for the purpose of both assessing and then verifying, but the earlier you can start, the better off your project is likely to be.

What Information is Necessary to Carry Out An SAP Assessment?

An SAP assessment involves three stages: the as-designed stage, the build stage and the as-built stage. As you might imagine, the information necessary to carry out an SAP calculation varies based on the stage that you’re in. Here’s a closer look at each stage and some of the information that is required and what each stage entails:

  • As-designed: This stage is early in the development process, typically around the time a project is designed and drawings are finalised. The data you’ll need to put into the SAP calculation software based off assessor-determined performance includes total floor space of both the dwelling and living area, external window and door dimensions, areas of heat loss, roofs, openings, ventilation, primary and secondary space heating, and renewable or energy-efficient technologies, among others. After the appropriate data is entered into the software, a determination will be made as to whether or not it complies with defined building regulations. If it doesn’t, you’ll likely have to go back to the drawing board and make adjustments and changes so that it can pass, and then you can move on to construction on the project. If it does pass, the SAP assessor will submit a Predicted Energy Assessment to the Building Control department.
  • Build: Technically, you don’t need to carry out another SAP calculation during the build stage. Usually, just performing one during the as-designed stage and then again at the as-built stage is enough. However, if you make any changes to the development as it is being constructed for one reason or another, it’s always wise to carry out another SAP calculation to make sure that you’re staying in line with your initial targets. Remember, you’ll still need to meet Building Regulations requirements at the end of any project – and the development will have to prove that it does when it undergoes the SAP calculation at the end of construction in the as-built stage. It behooves you to work with an SAP assessor to make sure that any changes won’t jeopardize approval.
  • As-built: Fitting to the name, these calculations are carried out after the property has been built and help determine the building’s final EPC. What does the SAP calculation process look like in the as-built stage? Simply put, it will double check that it still meets the requirements that it checked off when the SAP calculation was performed in the as-designed stage. If you made any changes since the as-designed calculation was performed, they’ll be indicated here. If you do make changes to the development, we caution you to be certain that whatever you did won’t jeopardize the regulations you have to meet with your property. And if you cannot meet the set regulations, then it won’t be able to receive its final approval, thereby meaning you won’t be able to sell it or rent it out.

Top Tips for Passing an SAP Calculation

Start Early

Like we’ve noted throughout this post, the sooner you begin considering the SAP calculation process, the better your results are likely to be in the long run. Starting early doesn’t just set up a development well in terms of complying with regulations, but it can also save time in redesigning or re-work that may need to be performed if the property does not meet current building regulations. The last thing you want is to turn an in-progress development upside down because it won’t be able to pass an SAP calculation.

Conduct an Air Pressure Test

Heat loss during the winter and cool air loss during the summer primarily occurs via air loss. Noting this, the more airtight a property is, the better it will fare when it comes to meeting energy efficiency and sustainability goals. On this note, consider administering an air pressure test to assess the development’s current status and see if any improvements can be made.

Focus on the Fabric

Fabric is another major source of heat loss. However, a manageable way to improve this is by increasing the insulation in a property. This, in turn, will enhance the property’s thermal performance.

Incorporate Other Sustainable Features

There are a bevy of sustainable features that you should be considering with any new development, and they range from windows to lighting to how the property is heated.

We urge you to pay attention to all of the little sustainable features that make up a property. After all, when it comes to meeting or succeeding energy efficiency goals, it’s often not one big thing that can make it happen, but many smaller things that can make a big difference when they’re all added together. Noting this, here’s a look at some of the sustainable features you may want to emphasize with any new residential development:

  • Heat controls and temperature control zones.
  • Renewable energy sources, such as solar panels, wind turbines or even hydroelectric power.
  • Insulation.
  • Windows that offer high levels of thermal performance.
  • Energy efficient lighting

How Sustain Quality Can Help

Now that you know a bit more about SAP calculations, why they’re important and when to begin the process, we strongly encourage you not to leave this important aspect of the development process to chance.

That’s where we at Sustain Quality can help, as we’ll partner with you on SAP calculation services and to help you make more informed decisions about how to design and what to include in the development.

We can also assist with any current developments and help them to improve their carbon footprint over time by mapping out concise and practical strategies. Contact us today for more information and to get started with a successful SAP calculation.

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We are a friendly team of Engineers delivering Sustainability and Building Compliance Solutions for developments in the Commercial and Residential sectors, which include Energy Statements, Noise Impact and Vibration Assessments, BREEAM Assessments, and Air Quality Assessments in the Environmental, Social and Governance sectors.

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Sustain Quality Ltd

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01372 438039