Sap Calculation Company London

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Sap Calculations Questions, See Whether We Have An Answer Here.

Just what Are Sap Calculations?

This is by far the most common query asked. Check out Andrea’s video explanation above, or read the full explanation here on the right.

Sap Calculations, How Do They Cost
We will be pleased to offer you discounts, for example for multiple dwellings that are of the same or similar design. For single dwellings then you would be looking in the region of £120 – £300 dependant upon the difficulty of your design along with the dimensions. By supplying the plans, you will be able to get a fixed price quotation.
What Are As Built SAP Calculations

These will be the final set of SAP calculations produced when the building has actually been completed to show that it is compliant with Part L1A of the building regulations. Prior to the project starting, it should have had a set of “Design Sap” calculations to demonstrate that the proposed dwelling, on paper at least, would be compliant with Part L1A.



How To Do Sap Calculations

Unfortunately this is not something you could do by yourself. Sap calculations need to be carried out by an On Construction Domestic Energy Assessor or OCDEA, by using approved Government software. The Assessor needs to be approved under one of the certification schemes and is also regularly audited to keep up their certification.

What Info is Needed For Sap Calculations

Your Assessor would advise you of exactly what is needed. Typically you would need the following:

  • Floor Plans to include sections and elevations
  • Orientation of the property
  • Construction specification of walls, roof and floors
  • Specification for all doors and windows
  • Primary and secondary heating
  • Provision for providing  hot water
  • Any renewable technology (if any)


Sap Calculations For New Build
All new dwelling need to have Sap calculations to prove compliance with Part L1A (Conservation of fuel and power in new dwellings) of the building regs.
Sap Calculations For Extensions
It’s now quite trendy to have large bi-folding doors, sky lights and large quantities of glazing on new extensions. However under the existing building regulations the quantity of glazing can be a maximum of 25% of the floor area of the new extension. So over compensations in the thermal elements in other places of the property will have to be made to show that the CO2 emissions coming from the current house and the proposed extension is no worse than the existing house and an extension where the glazing is within the allowed amount judged against Part L1B of the building regulations.

You need SAP calculations to find solutions and show compliance.


Sap Calculations For Conversions
When you are altering the use of a building, you will require Sap calculations. {The new dwelling will have to comply with Part L1B of the building regulations.}


Do I Need Sap Calculations
p>You will need Sap calculations for any of the following: 

  • Building a new property
  • Changing the use of an existing property (e.g, a barn conversion, commercial building to residential)
  • Extensions with more than 25% glazing
  • Opening up the main house to an existing conservatory
  • Extension where the extension is more than 50% of the original property wall area
  • Garage conversions
  • If requested by building control

This list is not exhaustive. Phone us, if you are unsure if you require them.


Just what Are Sap Calculations?

If you are reading this, you’ve more than likely recently been asked by somebody, typically your building control officer, to provide sap calculations for your building project.

You can click on the video clip on this page, where Andreas will shed some light on this, or continue reading.

SAP is short for Standard Assessment Procedure and it is the united kingdom government’s way of determining the energy performance of buildings. The calculations are necessary to illustrate that your building complies with certain energy targets set down within the building regs.

That’s basically it in a brief summary.

Sap calculations tend to be needed for 3 reasons

1. For all newly built homes
2. For a dwelling change of use, for example altering a commercial building to residential flats.
3. For overglazed extensions

There are two main targets that the sap calculations are required to demonstrate. Firstly that the dwelling emission rate (DER) and the dwelling fabric energy efficiency (DFEE) comply with certain targets.

A good set of building drawings must be provided to the Assessor, as all the calculations are done from the building drawings ,so there is no need to visit the property. Your Assessor will advise you of precisely what is needed. When the calculations are done, an Energy Performance Certificate or EPC can also be created.

Your Assessor can provide further advice in the event the calculations show that your building isn’t compliant, as well as let you know which is the best changes to make. It’s very important to liaise with your Assessor as early on in the project as possible because once the building is finished any non-compliances could possibly be quite costly to rectify.

If you require advice on a project you may have in or around London, or require a quotation, give us a call or fill in our get a quotation form.


Our Services


SAP For Dwelling Change Of Use

  • Reports for Part L1B Compliance
  • Free Advice

SAP For Overglazed Extensions

  • Carbon Emissions Reports
  • Heat Loss Calculations
  • Free Advice

SAP For New Builds

  • Reports for Part L1A compliance
  • Free Advice

What You Can Expect From Us

Trusted & Experienced

Our Assessors are fully qualified and accredited with years practical experience carrying Sap calculation in London . We also cover the whole of the UK and can assist on any project nationally.

Reliable & Fully Insured

You will be allocated a dedicated Assessor who is also covered by full professional indemnity insurance up to £100,000 so you know you’re in save hands.

Prompt Service

We’ll respond to your enquiry within 24 hours. We’ll also help you to deliver your project within your timescale.

Satisfaction Guaranteed

We aim to provide 100% satisfaction and look forward to working with you.


Get A Quote, Or Call Us For Advice