Increase your knowledge or check your processes for best practice when gathering documentation.

Stay compliant with data protection

In July 2020, the BER Code of Practice was updated to outline the roles and responsibilities of BER/DEC assessors in relation to GDPR, data protection and the processing of personal data.

To keep yourself and your business compliant with the relevant data protection regulations you should be familiar with:

  • the updates in the Code of Practice
  • your obligations under the data protection regulations within your business

Code of practice and GDPR

Use the Code of Practice as a guide when publishing and processing BER assessments and assessment data. This will help you to understand and comply with your obligations under GDPR.

All information obtained for a BER assessment should be processed, maintained, used, shared and stored in a secure manner. This is set out in Section 10 of the Code of Practice.

Further information

For information about your obligations under the data protection regulations, visit the Data Protection Commission.


Documentary evidence

Supporting documentary evidence forms part of the BER data file. It's collected to complete and support BER assessments. Documentary evidence has the potential to contain personal data.

Personal data

BER Assessors must avoid collecting unnecessary personal data or sensitive information when gathering and uploading documentary evidence.

Personal data is data that relates to or can identify an individual. This can be either by itself or together with other available information. Examples include a person’s name, contact details, bank details or other information that may be used to identify an individual.

Further information

For more information refer to Section 4.3 of the DEAP Survey Guide.

How to avoid collecting personal data

Reduce the risk of a data breach by eliminating the collection of personal data. This guidance shows you how. If you cannot avoid collecting personal data, you must remove the information before uploading it to DEAP.

Evidence Potential unnecessary personal dataGuidance
Declaration of Works Form
Utility bills
Receipts and invoices
Homeowners name
Bank account numbers
Utility account numbers
Cover any personal information before taking photos or copies of documents.
Photographs Occupants
Family photos and certificates
Religious symbols
Vehicle registrations
Before taking a photo check and remove any personal data in the frame.

Quality of documentary evidence

The documentary evidence you collect and upload should always be legible. If you are taking a photograph of a document, please check that the image is in focus and legible.

Key evidence

Key evidence is documentation that supports the age of the dwelling and any extensions as well as non-default values. It must be uploaded to DEAP before publication of the BER.

Dwelling and extension age

The age of dwellings and extensions are key evidence, as they are the basis for many default values used in DEAP. You'll find guidance on evidence to support the age of dwellings and extensions in Section 5 of the DEAP Survey Guide. 

Non-default values

This key evidence includes documentation and photos to support all non-default values entered in the DEAP assessment. The typical evidence requirements for non-default entries in DEAP are as follows.

AreaMinimum evidence to support non-default entries in DEAP
Building Fabric U-values for floors, roofs, walls 
  U-values for windows and doors 
  Thermal bridging factors (<0.15) 
Ventilation  Air-permeability test result 
  Performance data for mechanical ventilation systems including photos of make/model where available 

Insulated ducting outside thermal envelope

Space Heating  Space heating efficiency (e.g. photos, manual of appliance including make/model and/or certificates of performance) for primary and secondary heating 

Central heating pump 


Designer/Installer sign-off form


Flow temperatures for heat pumps 

Water Heating 

Water heating efficiency  

  Shower flow rates including presence of flow restrictors 

Waste-water heat recovery performance  


Manufacturer’s declared loss 


Low water usage (less than 125 l/p/d) 


Insulated pipework


Solar water heating inputs

Lighting  Supporting information where ‘is lighting design known’ is selected.
Renewables  Renewable inputs, for example PV performance certificates and photographs 

About this list

  • This list gives the minimum requirements in relation to documentary evidence upload. You should upload any evidence you believe will be of use to future BERs.
  • This list does not represent the total evidence an assessor must retain to substantiate a published BER in accordance with Section 8 of the Code of Practice. Refer to the DEAP Survey Guide for guidance on documentary evidence that must be retained, and which will need to be produced for an audit. 

Documentary Evidence - Overview

13th January 2021

This webinar is designed to support BER Assessors in understanding the documentary evidence required to support a BER assessment. 

Overview webinar

Documentary Evidence - Certification

12th October 2021

This webinar covers the various sources of certified data, the information required on a certificate and how to establish if a certificate is acceptable for use in a DEAP assessment.

Certification webinar

Documentary Evidence - Thermal Bridging

8th December 2021

This webinar explains thermal bridging, the information required for a default thermal bridging factor of 0.08, a non-default thermal bridging factor with default psi values from Part L and certified psi values as an acceptable form of evidence to use in a DEAP assessment.

Thermal Bridging webinar

BER Helpdesk

Call: 01 808 2029