We've successfully completed SAP calculations (heat loss assessments) for countless highly glazed extensions, navigating various complexities and limitations.
Our 100% Compliance Rate is Your Guarantee
We boast a 100% success rate in achieving compliance with Approved Document L for highly glazed extensions. This means you can be confident your design vision won't be compromised when you choose us for your extension's SAP calculations.
Let us help you achieve your dream extension while ensuring regulatory compliance!
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SAP Calculations for Extensions
(Heat Loss Calculations)
Heat Loss Calculations for Highly Glazed Extensions – Expert Assessment & Advice to Guarantee Compliance
Building a beautiful extension with expansive glazing like an orangery or garden room? SAP calculations can ensure your vision aligns with building regulations (Approved Document L: Volume 1) through the 'Design Flexibility Criterion.'
These calculations, often referred to as "heat loss calculations," assess your extension's energy efficiency, which is particularly important with extensive glazing elements like bi-fold doors, large windows, and rooflights. Building control bodies are increasingly requesting SAP calculations for extensions with high glazing levels due to potential heat loss concerns. Don't worry, we can help! Our expertise can guide you through the SAP calculation process for your glazed extension project, ensuring it meets regulations without sacrificing your design aspirations.
For any inquiries or a free quote on SAP Assessments, contact us at 0123 4567 890 or complete the form below.
Do I need a SAP Calculation for my Extension?
Building regulations (Approved Document L: Volume 1) limit glazing in extensions to 25% of the new floor area (including existing windows removed) to prevent excessive heat loss. Glass typically has lower thermal performance compared to well-insulated walls and roofs.
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Extensions complying with this 25% limit don't require mandatory SAP calculations.
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However, the growing desire for bright, airy spaces often leads to designs exceeding this limit. In such cases, SAP calculations become necessary.
When extension designs surpass the 25% glazing allowance outlined in Approved Document L: Volume 1, building regulations offer a "design flexibility" option. This allows you to proceed with your desired design if you can prove the completed dwelling will be as energy efficient as if a standard extension with less glazing had been built.
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One way to demonstrate compliance through this "design flexibility criterion" is by providing a SAP Calculation to the Building Control Body (BCB). This calculation assesses the entire dwelling's energy efficiency, taking into account the extension's increased glazing. By demonstrating that the overall efficiency meets regulations, you can achieve your dream extension with more glass.
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More on SAP CalculationsThey assess a home's annual energy use for heating, hot water, lighting, and ventilation based on standard occupancy and temperature settings. This allows for fair comparisons between different dwellings using an SAP Rating. SAP Calculations also estimate a property's annual CO2 emissions (Dwelling Emission Rate - DER) and its energy efficiency for the building itself (Dwelling Fabric Energy Efficiency - DFEE) and energy use from renewable sources (Dwelling Primary Energy Rating - DPER) - England only. In new builds, these figures must be lower than set limits (Target Emission Rate - TER, Target Fabric Energy Efficiency - TFEE, Dwelling Primary Energy Rating - DPER) to comply with building regulations (Approved Document L: Volume 1). Finally, SAP calculations are used to generate On-Construction Energy Performance Certificates (EPCs) for all new dwellings.
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Best Time for SAP CalculationsEarly design stage: Once you have internal layouts and a basic building plan, it's ideal to complete your SAP calculations. Benefits of Early Completion: Easier to make adjustments if needed based on the assessor's recommendations. Fulfills most Building Control Body (BCB) requirements for design stage calculations before construction starts. Final Stage: After construction is complete, the initial SAP assessment is updated to reflect the final building ("As Built"). This final calculation is used to generate your On-Construction Energy Performance Certificate (EPC).
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What Affects Your SAP Rating?Your home's SAP Rating considers several aspects that influence its energy use and CO2 emissions: Building Features: Location, orientation, wall construction, window efficiency, air leakage (from air tightness test). Building Systems: Heating and hot water system efficiency (including fuel type), ventilation system type. Energy Use: Internal lighting usage, solar heat gain from windows. Renewables: Presence of renewable energy technologies. A higher SAP Rating indicates better energy performance.
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Who Can Do SAP Calculations?For efficiency and to obtain an On-Construction EPC, a qualified and accredited On-Construction Energy Assessor is best. They're the only ones authorized to issue the final certificate. Our Recommendation: Choose an assessor with experience in all SAP versions and current Building Regulations to avoid costly mistakes during construction.
How can Big Boss help with SAP Calculations?
We would like to establish long-term collaborations with real estate agents and independent contractors by providing exceptional customer service and dependable technical advice.
Our SAP Calculation service includes all necessary guidance and suggestions as part of our commitment to make sure your project complies with the relevant building regulations in a sensible and economical way.
Requirements for compliance shouldn't keep you back! Our accredited assessors and energy consultants have the know-how to identify and address your difficulties on your behalf.
Independent & Cost-Effective
We focus solely on energy compliance services. Free from material sales or commissions, we prioritize providing the most cost-effective solutions to meet your compliance needs.
Competitive Pricing
We offer clear, affordable, all-inclusive fixed fees, with large savings offered for multi-unit constructions.
Expedited Service Available
We are aware of how quickly things are developing. Give us a call if you need energy calculations or pressure testing right away, and we'll do everything we can to assist.
Client Focused
We design our services with you and your unique needs in mind. In our industry, a one-size-fits-all strategy is not appropriate.
One Stop Solution
Our wide range of additional services, which we offer from planning to completion, helps to simplify our clients' compliance requirements.
Ongoing Technical Support
Plans and specifications are subject to change. To avoid any regulatory issues when a development is finished, we are accessible to offer technical support during the entire process.