Sap Calculations Redbridge

Easy and quick Sap computations from local professional Surveyors. Call us to get a quotation on your project.

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Sap Calculations, What are They?

For anyone who is reading this, you’ve probably been requested by someone, usually 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 either click the video recording on this page, where Andreas will shed some light on this, or continue reading.



Redbridge SAP Calcs For Dwelling Change Of Use

  • Reports for Part L1B Compliance
  • Free Advice

Redbridge SAP Calcs For Overglazed Extensions

  • Carbon Emissions Reports
  • Heat Loss Calculations
  • Free Advice

Redbridge 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 UK government’s method of calculating the energy efficiency of dwellings. These calculations are necessary to demonstrate that a building conforms with certain energy targets set down in the building regulations.

That’s more or less it in a simple overview.


When Are SAP Calculations Needed?

Sap calculations usually are required for three main reasons

1. For all new properties
2. For a dwelling that’s changed its use, e.g altering a single family home to residential flats.
3. For a planned extension having in excess of 25 % glazing

The two main areas that the sap calculations will be looking at is that the carbon emissions from your property are within set tolerances and that particular elements of the property, such as the windows, roof, floors and walls comply with specified thermal targets.

A good set of building plans must be given to the Assessor, as all the calculations are done from the building plans . Your Assessor will advise you of precisely what is needed. Once the calculations are done, an Energy Performance Certificate or EPC can also be created.

If your sap calculations show that your property isn’t compliant, the Assessor will give you advice on upgrades that can be made to make it so. It can be expensive if you realise at a late stage in the construction that the building isn’t compliant. So it’s best to liaise with your Assessor as early on in the project as possible, ideally before any building commences.

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


Sap Calculations Questions, Check If We Have The Answer Here.

Sap Calculations, What are They?

This really is quite possibly the most frequent question 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, in particular for multiple dwellings that are of the same or very similar construction. For single dwellings you would then be looking in the region of £120 – £300 dependant upon the complexity of the building and the measurements. By providing the plans, it will be possible to get yourself a fixed price quotation.

What Is The Difference Between Sap and EPC

Before we get to the differences, this is what you will need depending on your project.

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 demonstrate the energy effectiveness of a property. EPC is short for Energy Performance Certificate and it’s a summary statement from the SAP calculations in an easy to understand document, that could also be used to market or rent a property.

There are actually 2 types of EPCs. First is a SAP EPC which is produced from building plans where all of the elements of the building are known. This would normally be needed by building control to show that a property satisfies certain targets required by the building regulations. Building control would must also see the SAP calculations which illustrates in detail whether all of the elements going into the property comply with the building regulations.

The second sort of EPC is the common one that will be required when you are selling, or renting a property. This sort of EPC uses what’s called rdSAP, which is short for Reduced Data Standard Assessment Procedure, which is used where specified thermal values of, such as, the walls, roof, floors, etc, usually are not precisely known on an existing property. In this instance assumed thermal values are used depending on the age of the property. This kind of 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 require are the Sap calculations (which is the data behind the EPC) and the SAP EPC (which is actually summary report from the Sap calculations).

If you are still confused, then phone us for additional assistance.

What Are As Built SAP Calculations

These are the final set of SAP calculations generated when the building has been completed to show that it is compliant with Part L1A of the building regulations. Ahead of the project starting, it ought to have had a set of “Design Sap” calculations to show that the proposed building, in theory at least, would be compliant with Part L1A.



Can I Do The Sap Calculation Myself

No, this is not some thing you can do by yourself. The calculations have to be done by an On Construction Domestic Energy Assessor or OCDEA, using approved Government program. The Assessor must be approved under one of several accreditation schemes and is 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

Every new property 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 trendy to have large bi-folding doors, sky lights and large amounts of glazing on new extensions. But under the present building regulations the amount of glazing must be a maximum of 25% of the floor area of the new extension. Therefore over compensations on the thermal elements in other places within the property will have to be made to demonstrate that the CO2 emissions from the existing house along with the proposed extension is no worse than 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 show compliance.


Sap Calculations For Conversions

If you are changing 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

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. If you’re not certain whether you need them, then simply give us a call.


Our Services

What You Can Expect From Us

Trusted & Experienced

Our Assessors are fully certified and accredited with several years practical experience carrying Sap calculation in Redbridge . We also cover the whole of the UK and can help on any project nationwide.

Reliable & Fully Insured

You will be assigned a dedicated Assessor who is also covered by full professional indemnity insurance of up to £100,000 which means 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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