IDEA Ltd offer a range of services and advice that cover the different sectors of energy assessment and certification. See the details below of the services we offer and when they are required.
Domestic EPCs
Domestic Energy Performance Certificates (EPCs) are the type of certificate that most people are familiar with. These were introduced in 2007 to give an indication of the energy efficiency of a house or flat. The domestic EPC is sometimes referred to as an RDSAP EPC, this indicates that it is a Reduced Data Standard Assessment Procedure analysis, in other words a simplified version of the process used on new build houses.
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An EPC is required by law whenever a house or flat is marketed or sold. If the property is being rented, the EPC is required when there is a change of tenant. The EPC rating must be displayed on any marketing material for a property.
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An EPC will also be required if a property is being assessed with a view to a PV installation so that the Feed In Tariff can be calculated.
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Currently EPCs are valid for a period of ten years, however if improvements are made to the property the owner may wish to commission a revised EPC before the end of this period to reflect the improved rating.
Commercial EPCs
Commercial (or non-domestic) Energy Performance Certificates (EPCs) are produced for the same reasons as domestic EPCs. A commercial EPC assessment is notably more detailed than a domestic EPC.
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These were introduced in 2008 so as to give an indication of the energy efficiency of a commercial building (offices, warehouses, shops, factories etc).
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An EPC is required by law whenever a building is marketed or sold. If the property is being rented, the EPC is required when there is a change of tenant. The EPC rating must be displayed on any marketing material for a property. An EPC will also be required if a property is being assessed with a view to a PV installation so that the Feed In Tariff can be calculated.
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Currently EPCs are valid for a period of ten years, however if improvements are made to the building the owner may wish to commission a revised EPC before the end of this period to reflect the improved rating.
On Construction EPCs
(SAP calculations)
Building Regulations (Part L) states that SAP calculations have to be carried out when new dwellings are built, whilst conversions, renovations and extensions require L1b compliance.
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Our extensive experience has enabled us to carry out these assessments and also to advise how compliance may be achieved if it is not achieved initially. we are experienced in working with all versions of SAP since 2005, the latest being the basis of the 2021 Building Regulations.
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We are fully accredited to issue Predictive Energy Assessments (PEAs) and On construction Energy Performance Certificates (OC EPCs). All calculations are carried out using Elmhurst Energy Systems Design SAP software. All assessments are accompanied by a client letter along with the required documentation.
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The assessment is carried out from plans and building specifications supplied by clients.
DECs – Display Energy Certificates
All public buildings over 250 square metres require a Display Energy Certificate (DEC). This needs to be displayed in a prominent position. In addition to this an Advisory Report is required in the first year, which lists cost-effective measures to improve the energy rating of the building.
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The DEC is an operational rating and reflects the energy usage per square metre, unlike a Commercial EPC which is an Asset Rating and reflects the inherent energy properties of the building.
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For buildings 250-999 metres square DECs and Advisory Reports are required to be renewed every 10 years. For buildings over 1000 metre square DECs and Advisory Reports are required to be renewed annually.
Part O - Overheating mitigation
From 15 June 2022 all new residential buildings must demonstrate compliance with Part O of the Building Regulations.
Part O states that reasonable provision must be made in respect
of a dwelling to (a) limit unwanted solar gains in summer; (b) provide
an adequate means to remove heat from the indoor environment.
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We can provide documentation to demonstrate Part O compliance using the 'Simplified method' as outlined in Approved Document Part O.
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We do not carry out Dynamic Thermal Modelling. If your property is located in London, has extensive glazing facing south or west, and/or
a single glazed façade with no cross ventilation (eg. Apartments) then you will likely need to demonstrate Part O compliance through the Dynamic Thermal Modelling method.
U-value calculations
A U-Value Calculation measures the thermal transmittance (transfer of heat) of each material used within a structure/ building. The lower the total U-value is, the slower the heat is transmitted in and out of the building.
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As qualified SAP assessors we can carry out U-value calculations. A U-Value calculation is a computer-based assessment that measures the total thermal resistance of a structure. The unit of measurement for U-Values is given as W/m2K (Watts per square metre degree Kelvin); these are calculated through an approved U-Value Calculator which takes into account the material thickness and conductivity (K-Value).
Floor plans
We can provide professional 2D floor plans for marketing particulars.
Please advise if a floor plan is required prior to us carrying out an EPC survey and we will make note of any additional information required for producing a floor plan.