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Energy and SAP Ratings Explained

Oct 24, 2022
Energy and SAP Ratings Explained

There are different types of SAP ratings and energy available for residential buildings. These ratings differ from energy efficiency ratings in that they are based on fuel costs. The latter is based on environmental impact. Performance indicators are based upon the estimated annual energy consumption and encompass space heating and domestic water, lighting and ventilation, appliances and lighting. Other outputs include cooling load and the potential for overheating in the summer.

Predicted Energy Assessment (PEA).

A Predicted Energy Assessment is a calculation that is based on the SAP (Sustainable Assessment Protocol) and the Environmental Impact Rating (EIR) of the building. A PEA is essential when a construction project is planned. Predicted Energy Assessments should be carried out during the design phase to ensure that any possible issues can be resolved prior to the building is completed. The PEA is generally prepared by On Construction Energy Assessors, who are certified by an approved scheme of the Government.

People who are building a home need to obtain an PEA. They provide information on the energy performance of a building, and can be used to ensure the building regulations are in compliance. sap calculation are not as comprehensive as an EPC however they can still be useful to make sure that a building is meeting energy efficiency targets.

Air pressure test

Air pressure testing is an essential component of the Energy Performance Certificate process, which is required under Part L1A of the Building Regulations. The test is conducted by increasing the air pressure inside the house and determining how quickly it returns to normal. It is conducted by inserting large fans into the entrance doorway. The quantity of units being developed and the assumptions made by the SAP assessor will determine the number of tests that are required.

It is likely to fail the SAP Energy Rating if air permeability isn’t assessed for all areas of the building. This will need remedial work. The best method to avoid this is to perform an air permeability test before the building is completed, rather than waiting until the very last minute.

CO2 emissions

The UK government released a revised version of the Standard Assessment Procedure (SAP) that reduces by half the CO2 emissions factors used for electricity. The new SAP 10 assumes that there is an average of 233 grams CO2 per Kilowatt (as instead of 519 grams in the old SAP). This new factor has been created to reflect the increasing the renewable energy use and the grid for energy.

The SAP rating estimates a building’s energy costs which includes the cost of heating, lighting, and renewable technologies. The rating is based on an index ranging from 1 to 100. Higher numbers indicate lower costs and lower CO2 emissions. It also measures a dwelling’s CO2 emissions from the dwelling, which shows if it is in conformity with Building Regulations.

Target Emission Rate (TER)

The Target Emission Rat (TER) is an instrument for quantifying carbon emissions from buildings. It has been in use since 1993 and forms the basis of many Government initiatives in the energy and environment sector. The most current version of SAP is SAP2012 and has been upgraded several times since then. It’s still a reliable method for assessing the carbon and energy efficiency of buildings. It allows for like-for-like comparisons of different properties. It is not without fault and will be replaced by end 2021 by new building regulations.

The SAP model is based on the building’s location and aspect and fabric construction materials and thermal junctions. This information can be used for measuring the loss of heat and gain for each room. Oftentimes, people are surprised to learn how much energy a building needs. The TER rating isn’t the only factor to be considered. The SAP rating will also take into account the energy costs associated with space lighting, heating, ventilation and other associated costs. This information is then adjusted to reflect the floor space of the building.