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Sap Calculations Bristol

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So, What Exactly Are Sap Calculations

If you are reading this, you have probably been requested by someone, typically your building control officer, to provide sap calculations for your building project.

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



Bristol SAP Calcs For Dwelling Change Of Use

  • Reports for Part L1B Compliance
  • Free Advice

Bristol SAP Calcs For Overglazed Extensions

  • Carbon Emissions Reports
  • Heat Loss Calculations
  • Free Advice

Bristol SAP Calcs For New Builds

  • Reports for Part L1A compliance
  • Free Advice

What does SAP mean?

SAP is short for Standard Assessment Procedure and it is the united kingdom government’s method of determining the energy performance of dwellings. These calculations are necessary to prove that a building conforms with specified energy targets set down in the building regulations.

That’s basically it in a brief overview.


When Are SAP Calculations Needed?

Sap calculations usually are required for three main reasons

1. For all newly built dwellings
2. For a dwelling that’s changed its use, such as altering a commercial building to domestic flats.
3. For extensions that have over the permitted amount of glazing

The 2 main areas which the sap calculations will be looking at is that the carbon emissions from the dwelling are within set tolerances and that certain components of the property, for example the windows, floors, roof and walls comply with certain thermal energy targets.

Sap computations are done by a professional and approved On Construction Domestic Energy Assessoror OCDEA for short. There is not any need to visit the property because all the computations are carried out from the building drawings . After the calculations are done, an Energy Performance Certificate or EPC can also be created.

Your Assessor can provide you with additional advice in the event the calculation show that your dwelling isn’t compliant, as well as tell you which will be the best changes to make. It may be costly if you realise at a late stage in the construction that the building isn’t compliant. So it is best to liaise with your Assessor as early on in the project as possible.

Should you need advice on a project you may have in , or require a quotation, contact us or fill in our get a quote form. We’re here to help.


SAP Calculations in Bristol The Ten Most Usual Questions Asked.

So, What Exactly Are Sap Calculations

This is probably 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 provide discounts, for example for multiple dwellings that are the exact same or similar design. For single properties then you would be looking in the range of £120 – £300 depending upon the difficulty of your design and also the measurements. By providing the plans, it will be possible to get yourself a fixed quotation.

What’s The Difference Between Sap and EPC

Before we explain the difference, this is what you will require 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 buildings design that’s created to show the energy effectiveness of a property. An EPC or Energy Performance Certificate is a overview report derived from the Sap calculations that produces a SAP rating from 0 to 100. This rating is expressed on the Energy Performance Certificate as A the highest to G the lowest. It will also list recommendations that would improve the rating of your dwelling.

There are really 2 kinds of EPCs. The first is a SAP EPC that is created from building plans where all the components of the construction are known. This will normally be needed by building control to show that a dwelling meets specified targets essential to the building regulations. Building control would also need to see the SAP calculations which shows in detail whether the many elements going into the property comply with the building regulations.

The second form of EPC is the standard one that will be needed for anyone who is marketing, or renting a property. This particular EPC uses what’s called rdSAP, which means Reduced Data Standard Assessment Procedure, which is used where particular thermal values of, for example, the walls, roof, floors, etc, are not precisely known on an established property. In this instance assumed thermal values are used depending on the age of the property. This type of EPC will be no good to show compliance with any building regulations. Sometimes building control would simply ask you for the EPC, but what they would really need to have are the Sap calculations (which is the data behind the EPC) and the SAP EPC (which is actually summary report from the Sap calculations).

Still perplexed, then simply call us to get more advice.

What Are As Built SAP Calculations

These will be the finished set of SAP calculations generated once the dwelling has actually been completed to hopefully demonstrate that it is compliant with Part L1A of the building regulations. Ahead of the construction starting, it ought to have had a set of “Design Sap” calculations to show that the planned dwelling, on paper at least, will be compliant with Part L1A.



How To Do Sap Calculations

No, this is not something that can be done yourself. Sap calculations have to be done by an On Construction Domestic Energy Assessor or OCDEA, working with approved Government software programs. The Assessor must be certified under one of several certification schemes and is also regularly audited to keep up their accreditation.

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 Sap calculations to demonstrate compliance with Part L1A (Conservation of fuel and power in new dwellings) of the building regulations.


Sap Calculations For Extensions

It’s now quite fashionable to have large bi-folding doors, sky lights and large quantities of glazing on new extensions. But under the existing building regulations the quantity of glazing can be no more than 25percent of the floor area of the new extension. Therefore over compensations on the thermal elements in other areas within the property will have to be made to demonstrate that the CO2 emissions coming from the current house and the planned extension is no worse when compared to the existing house and an extension where the glazing is within the allowed amount judged against Part L1B of the building regulations.

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


Sap Calculations For Conversions

For anyone who is altering the use of a dwelling, you will need Sap calculations. {The new dwelling will have to comply with Part L1B of the building regulations.}


Will 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 checklist is not exhaustive. Phone us, if you are uncertain if you need them.


Our Services

What You Can Expect From Us

Trusted & Experienced

Our Assessors are fully certified and accredited with years experience carrying Sap calculation in Bristol . 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 up to £100,000 to ensure 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