A home featuring an EPC score surrounded by plants and money, representing the benefits of a good RdSAP score

What is RdSAP?

RdSAP stands for Reduced Data Standard Assessment Procedure. It is a simplified version of the SAP (Standard Assessment Procedure) used in the UK to assess and compare the energy performance of residential dwellings.

RdSAP is used to produce Energy Performance Certificates (EPCs) for existing homes. These certificates are required when a property is sold, rented, or built.

A man surveying a house for rdsap

Why "Reduced"?

The full SAP method is detailed and requires comprehensive building data, which is typically only available for new builds. For existing buildings, it’s often impractical to gather this level of detail.

A ‘Reduced’ version of SAP (RdSAP) allows assessors to carry out assessments faster and with less invasive surveying.

 

What does RdSAP assess?

RdSAP assesses many aspects of your home. Some of which include:

  • Heating system type and controls
  • Insulation (loft, walls, floors)
  • Windows (double/single-glazed)
  • Construction type
  • Lighting
  • Renewable energy systems (solar panels, etc.)

How it can affect you?

If You're a Homeowner

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Considering selling your home? You’re legally required to have an EPC based on an RdSAP assessment. Without it, you can’t sell the property.

The EPC also gives recommendations (from RdSAP) on how to make your home more energy-efficient – e.g. adding insulation, upgrading heating and water systems, etc. These improvements can lower your energy bills, increase your property’s value, and even make your home more attractive to potential buyers.

If You're a Landlord

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Since April 2020, in England and Wales, most rented properties must have a minimum EPC rating of E. Properties rated F or G are not legally rentable (with few exceptions).

Renting a property without a compliant EPC could result in fines of anywhere between £5,000 and £30,000 (depending on the region and circumstances).

Furthermore, if your property is below E, you may be required to carry out work (e.g. insulation, boiler upgrades) suggested by the RdSAP based EPC.

If You're a Tenant

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The EPC tells you how energy-efficient your home is. A low rating (E, F, or G) often means higher heating bills and a potential for damp or cold living conditions.

If you find your rental home is below an E rating, you may have a right to request energy efficiency improvements – and in some cases, landlords are obligated to comply.

RDSAP recognised water and energy efficient sustainable eco showers

Future legislation - What Does it Mean For Me?

EPC requirements may tighten. Already there are proposed schemes of a C rating minimum for rentals by 2028, so knowing your RdSAP rating now can help you plan ahead.

 

Kelda and RdSAP

Kelda eco showers are the first and only showers to be recognised within RdSAP through Appendix Q.

This means that the Government Department for Energy Security and Net Zero recognise that our eco showers reduce water use and waste less energy overall, supporting the UK’s transition to net-zero housing.

Kelda eco-showers are currently one of the best ways to reduce your water use per household – meaning our showers are a quick win when it comes to improving your EPC score!

RDSAP recognised water and energy efficient sustainable eco showers

Can Kelda help to improve your EPC rating?

Yes!

Kelda are the inventor of our patented high-efficiency Air-Powered™ shower technology.

This means that, unlike other low-flow showers that often compromise shower experience, Kelda’s technology delivers a high-quality shower, using air to deliver a full, high-pressure experience whilst cutting water, energy and carbon use by up to 55%.

Our eco-showers do this by using air to distribute the water droplets, causing the droplets to be 2.5x larger than the average shower with 15x more impact.

Our showers can also be used in tandem with a waste water heat recovery system, meaning that shower water waste is used to preheat the mains cold water – lowering carbon emissions, improving RdSAP scores and reducing household energy bills.

All of this whilst only using 4.5 litres of water per minute (unlike regular showers that use a shocking 8-15 lpm).

In Summary:

  • RdSAP (Reduced Data Standard Assessment Procedure) is the key to understanding and improving your home’s energy performance
  • EPCs (Energy Performance Certificates) are legally required and impact property value, compliance, and comfort
  • Minimum EPC rating for rentals may rise to C by 2028 – knowing your RdSAP rating now means you can plan ahead accordingly, futureproofing your home
  • Kelda showers are the only showers recognised by the government to be an effective way to boost EPC score and cut energy bills

Eager to find out more on how Kelda can help you improve your EPC?

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