Rayleigh Top Sap Assessors

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So, What Exactly Are Sap Calculations?

Have building control, or even your architect asked you to get sap calculations. Why do you need them and what are sap calculations anyhow? Then continue reading.

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



Rayleigh SAP Calcs For Dwelling Change Of Use

  • Reports for Part L1B Compliance
  • Free Advice

Rayleigh SAP Calcs For Overglazed Extensions

  • Carbon Emissions Reports
  • Heat Loss Calculations
  • Free Advice

Rayleigh SAP Calcs For New Builds

  • Reports for Part L1A compliance
  • Free Advice

What does SAP mean?

SAP stands for Standard Assessment Procedure and its the UK government’s method of determining the energy efficiency of properties. These calculations are necessary to prove that a building conforms with certain energy targets laid down in the building regs.

That’s basically it in a brief summary.


When Are SAP Calculations Needed?

Sap calculations tend to be required for 3 reasons
1. For all newly built homes
2. For a dwelling change of use, such as altering a single family home to flats.
3. For overglazed extensions

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

A good set of building plans will need to be given to the Assessor, since all the calculations are done from the building plans ,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 calculations are completed.

If your sap calculations show that your property isn’t compliant, the Assessor will give you recommendations on improvements that can be made to make it so. It may be costly if you find out at a late stage in the construction that the building is not compliant. So it is wise to liaise with the 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 Rayleigh , or simply require a quotation, contact us or fill in our get a quote form.


Sap Calculations Queries, Check If We Have The Answer Below.

So, What Exactly Are Sap Calculations?

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

What Is The Cost Of Sap Calculations

If there are various properties with similar types of constructions, then special discounts may apply. But typically for a single property the price would be in the area of £120 – £300. By providing the plans, it will be possible to get yourself a fixed price quotation.

What’s The Difference Between Sap and EPC

Before we get to the differences, this is what you will require 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 calculations of pre defined data set of a properties design that’s put together to demonstrate the energy efficiency of a dwelling. EPC means Energy Performance Certificate and it’s a summary report of the SAP calculations in an simple to grasp document, that can also be used to market or rent out a property.

There are actually two kinds of EPCs. The first is a SAP EPC that is created from building plans where all of the components of the building are known. This would normally be required by building control to demonstrate that a property complies with certain targets essential to the building regulations. Building control would must also see the SAP calculations which illustrates in greater detail whether all the components going into the property comply with the building regulations.

The 2nd variety of EPC is the regular one that will be needed when you are selling, or renting out a property. This sort of EPC uses what’s called rdSAP, which means Reduced Data Standard Assessment Procedure, which is used where certain thermal values of, such as, the walls, roof, floors, etc, are not precisely known on an existing property. In this case assumed thermal values are used according to the age of the property. This kind of EPC would be no use to demonstrate compliance with any building regulations. Sometimes building control would simply ask you for the EPC, however what they would really need are the Sap calculations (which is the data behind the EPC) and the SAP EPC (which is actually summary report of the Sap calculations).

Still confused, after that contact us to get more information.

What Are As Built SAP Calculations

These will be the finished set of SAP calculations generated when the building has actually been completed to confirm that it is compliant with Part L1A of the building regulations. Prior to the building starting, it ought to have had some “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 yourself. Sap calculations need to be done by an On Construction Domestic Energy Assessor or OCDEA, by using approved Government software programs. The Assessor must be certified under one of the certification schemes and is also regularly audited to maintain their qualification.

What Info 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 property need 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 fashionable 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 can 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 need to be made to show the CO2 emissions coming from the current house and the proposed extension is not any worse when compared to the existing house and an extension whose glazing is within the permitted amount judged against Part L1B of the building regulations.

You should have SAP calculations to find solutions and demonstrate 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 is not an exhaustive checklist. Give us a call, if you are unsure if you need them.


Our Services

What You Can Expect From Us

Trusted & Experienced

Our Assessors are fully qualified and accredited with years experience carrying Sap calculation in Rayleigh . We also cover the whole of the UK and can assist 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 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% customer satisfaction and look forward to working with you.


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