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Sap Calculations Wolverhampton

Do you need Sap calculations for either Part L1A, or Part L1B, we’re here to assist. Give us a call for a quote for your job.

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Sap Calculations, Exactly What Are They?

For anyone who is reading this, you have probably been recently asked by another person, normally your building control representative, to supply sap calculations for your building project. But you probably haven’t been told what sap calculation actually are and why you need them.

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



Wolverhampton SAP Calcs For Dwelling Change Of Use

  • Reports for Part L1B Compliance
  • Free Advice

Wolverhampton SAP Calcs For Overglazed Extensions

  • Carbon Emissions Reports
  • Heat Loss Calculations
  • Free Advice

Wolverhampton SAP Calcs For New Builds

  • Reports for Part L1A compliance
  • Free Advice

What does SAP mean?

SAP is short for Standard Assessment Procedure and its the UK government’s method of determining the energy performance of dwellings. Sap calculations are necessary to show that your building complies with specific energy targets laid down within the building regulations.

As a quick summary, that’s pretty much it.


When Are SAP Calculations Needed?

Here are most of the reasons you may well be asked for sap calculations

1. For all newly built properties
2. For a dwelling that’s changed its use, such as altering a single family home to residential flats.
3. For extensions that have more than 25% glazing

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 will need to be given 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. An EPC or Energy Performance Certificate can be produced once the computations are completed.

Your Assessor can give you further guidance in the event the calculation show your dwelling isn’t compliant, as well as inform you which is the most effective improvements to make. It could be costly if you realise at a late phase in the construction that the building isn’t compliant. So it is wise to liaise with your Assessor as early on in the project as possible, ideally before any building commences.

Should you require guidance on a project you may have in or around , or simply require a quote, give us a call or fill in our get a quote form. We’re here to help.


Rather than trawl through a entire website to get the answers you’re trying to find, we’ve provided answers to the ten most common questions asked about SAP in Wolverhampton.

Sap Calculations, Exactly What Are They?

This is certainly quite possibly 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

If there are a number of properties with similar types of constructions, then reductions may apply. For single properties you would then be looking in the range of £120 – £300 depending on the intricacy of your design along with the dimensions. By providing the plans, you will be able to get a fixed price quote.

What Is The Difference Between Sap and EPC

Before we explain the difference, this is what you will need depending on your job.

For a new build property you’ll need – SAP calculations and an EPC.

For dwelling change of use or conversion you’ll need – Sap Calculations and an EPC.

For overglazing on an existing dwelling you’ll – Sap calculations only.

SAP or Standard Assessment Procedure are the computations of pre defined data set of a properties design that’s created to display the energy performance of a dwelling. An EPC or Energy Performance Certificate is a summary report produced by the Sap calculations which produces a SAP rating from 0 to 100. This rating is shown on the EPC as A the highest to G the lowest. It will also list recommendations that would improve the rating of your property.

There are actually 2 types of EPCs. The first is a SAP EPC which is created from building plans where all the elements of the construction are known. This will normally be required by building control to show that a dwelling satisfies specific targets essential to the building regulations. Building control would also need to see the SAP calculations which shows in detail whether all of the components going into the property conform to the building regulations.

The second form of EPC is the typical one that would be required when you are selling, or renting a property. This sort of EPC uses what’s called rdSAP, which stands for Reduced Data Standard Assessment Procedure, and is used where particular thermal values of, for instance, the walls, roof, floors, etc, are not precisely known on an existing property. In this instance assumed thermal values are used according to the age of the property. This particular EPC would be no good to show compliance with any building regulations. Sometimes building control would simply ask you to get an EPC, but what they would really need are the Sap calculations (which is the data behind the EPC) and the SAP EPC (which is a summary report from the Sap calculations).

If you are still perplexed, then simply phone us for further information.

What Are As Built SAP Calculations

These are the final set of SAP calculations generated after the building has been completed to hopefully demonstrate that it is compliant with Part L1A of the building regulations. Prior to the construction starting, it should have had some “Design Sap” calculations to show that the proposed construction, on paper at least, would be compliant with Part L1A.



How To Do Sap Calculations

No, this is not something that can be done yourself. The calculations have to be done by an On Construction Domestic Energy Assessor or OCDEA, by using approved Government program. The Assessor has to be approved under one of several accreditation schemes and is also regularly audited to maintain their accreditation.

What Information is Required 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 require Sap calculations to prove compliance with Part L1A (Conservation of fuel and power in new dwellings) of the building regulations.


Sap Calculations For Extensions

It’s now popular to get large bi-folding doors, sky lights and large quantities of glazing on new extensions. However with the existing building regulations the quantity of glazing must be no more than 25% of the floor area of the new extension. So over compensations on the thermal elements in other areas of the property will have to be made to show that the CO2 emissions coming from the current house along with the proposed extension is no worse when compared to the existing house and an extension where the glazing is within the permitted amount judged against Part L1B of the building regulations.

You will need SAP calculations to find solutions and illustrate compliance.


Sap Calculations For Conversions

When you are modifying the use of a building, you will need Sap calculations. {The new dwelling will have to comply with Part L1B of the building regulations.}


Do I Need to have Sap Calculations

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 is not an exhaustive checklist. Give us a call, if you are not certain if you require them.


Our Services

What You Can Expect From Us

Trusted & Experienced

Our Assessors are fully qualified and accredited with many years practical experience carrying Sap calculation in Wolverhampton . We also cover the whole of the UK and can help on any job nationwide.

Reliable & Fully Insured

You will be allocated a dedicated Assessor who is also covered by full professional indemnity insurance of 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 seek to provide 100% satisfaction and look forward to working with you.


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