SAP Calculations – Myth Busters


Find out the FACTS from the FICTION...


"I don’t need a SAP calculation"

SAP calculations come in two forms - L1A SAP Calculations (new builds) & L1B SAP Calculations (extensions and conversions). A SAP Calculation has two main purposes - to demonstrate Part L Building Regulation compliance & also to produce an EPC. A SAP Calculation is required by law for building control sign off & an EPC is required by law when building, selling or letting a property.


"Aren’t SAP calculations and an EPC the same thing?"

Although they are closely related, a SAP calculation and EPC are not the same. This is because a SAP calculation is the methodology behind the EPC. Both documents are therefore required.


"Once a SAP calculation has been started, no design changes can be made"

We provide both Design Stage SAP Calculations and As Built SAP calculations. A Design Stage SAP calculation allows you to check the desired specification of the property meets Part L compliance.

As Built SAP calculations give results based on the specification once it is built, including the Air Tightness Test (or Air Permeability Test) result.

However, your Design Stage SAP Calculation can be updated still throughout the project. UK Building Compliance offers specification changes as part of our inclusive fee.


"The only way to achieve SAP compliance is by using renewables"

Whilst renewable technologies can certainly help properties fly through baseline Part L requirements, they are not a strict requirement under current Building Regulations. Ensuring that a property has low u-values and efficient heating will usually be enough to achieve compliance.

This however, is set to change once Part L standards are uplifted in June 2022. You can read more about this on our blog here.


"Isn’t electricity now better than gas?"

The current SAP 2012 methodology is outdated. The fuel factor for electricity is twice as carbon intensive as natural gas – because the National Grid figures are a decade old. However, a methodology update is expected next year which will demonstrate that electricity is now less carbon intensive than gas, thanks to a dramatic change in the makeup of the National Grid since 2010.


"So electric boilers/radiators are the future then?"

This is a very common misconception, not helped by recent misleading media headlines! Although standard electric heating is a more sustainable option, its running costs mean that it is not a viable option for the future. When updated in 2022, the SAP software will take the running costs of these systems into account. This means that electric boilers are not likely to meet compliance.

The regulations set out in the Future Homes Standard indicates that air source heat pumps should be adopted. Alternatively, gas boilers accompanied by renewable technologies will also meet regulations.


"Are heat pumps not the same as other forms of electric heating?"

The reason air source heat pumps will pass future Part L standards is because they run at efficiencies of up to 350%! This is almost 4 times as efficient as a gas boiler – which largely makes up for the price difference per unit between electricity and gas. This compares with electric boilers/radiators which, whilst often being almost 100% efficient, are still 3 or 4 times more expensive to run.

UKBC offers Stroma Certified SAP Calculations for new builds, extensions and conversions.  You need these calculations to make sure your building complies with Part L (England & Wales), Section 6 (Scotland) or Part F1 (Northern Ireland) of the most recent version of The Building Regulations.

Start Using UK Building Compliance Today

You may also like

January 25, 2024

July 12, 2022

June 27, 2022

June 23, 2022

May 17, 2022

May 12, 2022

Start Using UK Building Compliance Today