
At JosTec, we have a team of experienced in-house SAP assessors who are dedicated to providing accurate and reliable SAP calculations.
SAP Calculations are required by Building Regulations and Planning for all new builds, conversions and certain extensions. They assess how energy-efficient a property is, and help ensure it meets Part L1a of the Building Regulations.
If your project involves a new build, a conversion, or an extension with glazing over 25%, you’ll likely need a SAP.
Full SAP calculation
Government approved method to assess efficiency
Expert recommendations
Advice to help you achieve a pass
Document-ready reporting
Meets Part L1a of the Building Regulations
Assessments for all project types
We help with new builds, conversions & more
Clear submission requirements
We’ll tell you exactly what to send
Quick Turnaround
Fast-track available when you need it quickly

To carry out your SAP calculation and help secure Building Control approval, we’ll need a few key details from you:
Floor plans
Elevations and cross-sections
Site plans
Wall, floor and roof construction details
Heating system information
Details of any renewable technologies
Window specifications
At JosTec, we have a team of experienced in-house SAP assessors who are dedicated to providing accurate and reliable SAP calculations. Our service comes with a pass guarantee based on our expert recommendations, giving you peace of mind that your project will meet all necessary regulatory requirements.
Experienced in-house SAP assessors
Expert guidance to help you pass first time
Pass guarantee based on our recommendations
Quick turnaround service available
Fully compliant with Building Regs (Part L1a)
Friendly, helpful support at every stage
It’s a government-approved assessment that measures the energy efficiency of a residential dwelling, resulting in a rating from 1 (inefficient) to 100+ (highly efficient or energy-exporting).
You’ll need one for all new-build dwellings, conversions, material changes of use, and extensions with glazing over 25% of the floor area.
It indicates how energy-efficient a property is, based on estimated energy use and fuel costs.
We’ll need your architectural drawings (plans, elevations, sections), construction build-ups, window specs, and any renewable system details.

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