L1B – SAP calculations for conversions

L1B – SAP calculations for conversions

If you alter a building such that there is a material change of use, then we can provide SAP calculations to demonstrate compliance with Approved Document L1B.

A material change of use is defined to be where, after the change:

  • the building is used as a dwelling, where previously it was not;

  • the building contains a flat, where previously it did not; or

  • the building, which contains at least one dwelling, contains a greater or lesser number of dwellings than it did previously.

Compliance is achieved provided the calculated CO2 emission rate for all the dwellings within the proposed building is no greater than if each dwelling had been built to the minimum standards of Approved Document L1B.

The CO2 emission rate for each dwelling is calculated using SAP, the Government’s approved methodology for calculating the energy performance of dwellings.

Our experienced assessors can guide you smoothly through the process, offering the greatest level of design flexibility along the way.

How Energytest can help

Fast and accurate SAP calculations at a competitive price.

Comprehensive advice and support to ensure you arrive at the most economic and feasible solution to achieve compliance.

One fully-inclusive fee covering:

  • All the consultancy required to ensure every dwelling achieves a pass.
  • Design-stage and as-built SAP calculations.
  • U-value calculations.
  • Energy Performance Certificates.

Single-source-solution for Building Regulation compliance. As well as your SAP calculations and EPCs we can also provide Part G water calculations and Part F extract fan testing.

Newly restored residential stone barn with a slate roof in rural countryside against a blue sky with clouds.

We shall assess the dwellings based on the design-specification provided. The vast majority of projects we assess achieve a pass first time. If a pass is not achieved we shall put forward cost effective options to achieve a pass. For example, improvements to the heating system, increase in insulation or better performance glazing.

Once a satisfactory specification has been agreed we shall issue a copy of the SAP reports for submission to Building Control.

Upon completion of the construction works we shall update the SAP calculations to incorporate any changes to the design and issue a copy of the Energy Performance Certificate.

  • Floor plans, elevation drawings, section drawings and a site plan;

  • Construction specification;

  • Mechanical and electrical specification; and

  • Details of any renewable technology, such as solar hot water or photovoltaics.

What our clients say:

We have been using the services of Energytest Limited for over 10 years to provide us with SAP calculations, EPC’s, and Air leakage testing and have always found Jonathan and his team to be extremely helpful and professional at all times.

We would not hesitate in recommending Energytest.

L Watson – Challinor Hall Ltd