2035 Assessments
Based in Higham, Bury St Edmunds, Suffolk · Covers East of England and throughout the UK Accreditation stated by provider: TrustMark, Elmhurst, ECMK, RICS, CIOB, CIAT, MCSOwn websiteUK-wide
03 · Existing buildings & works · PAS 2035
Retrofit assessment
A retrofit assessment is the survey that starts any energy-efficiency project run under PAS 2035, the standard behind government-funded schemes and TrustMark-registered work. It records the home, its condition and how it is used, so the right measures can be planned safely.
DWGuide by Dan Wallis · Updated 27 September 2026
This guide covers the rules in England. See Wales, Scotland and Northern Ireland.
Who needs oneHomeowners and landlords improving energy efficiency under PAS 2035, including most funded schemes
Who can do itA qualified Retrofit Assessor working under a TrustMark-registered scheme
WhenAt the start, before measures are designed
64 retrofit assessors listed across the UK
Featured (paid) listings first, then A–Z · How we check listings
Find retrofit assessors by region
London (20) South East (12) East of England (8) South West (6) West Midlands (8) East Midlands (10) Yorkshire and the Humber (5) North West (12) Wales (4)
National providers (20)
AES Sustainability Consultants
Based in Tiverton, Devon · Covers England, Scotland and Wales Accreditation stated by provider: ATTMA, SITMA, Elmhurst, ECMK, TrustMark, BREEAM, PassivhausOwn websiteUK-wide
Base Energy
Based in Staines-upon-Thames, Surrey and Bootle, Merseyside · Covers UK-wide, including London Accreditation stated by provider: Elmhurst, CIBSE, TrustMark, BREEAMOwn websiteUK-wide
Building Energy Experts
Based in Bristol · Covers Nationwide Accreditation stated by provider: Elmhurst, ATTMA, TrustMark, Retrofit Academy (Corporate Member), Retrofit Academy Corporate Member, AECBOwn websiteUK-wide
Coactivation
Based in Derby · Covers Midlands locally, UK-wide for larger schemes Accreditation stated by provider: TrustMark, ElmhurstOwn websiteUK-wide
Compliant Retrofits Ltd
Based in Manchester · Covers UK-wide, including London Accreditation stated by provider: TrustMarkOwn websiteUK-wide
Crawford & Co Surveyors
Based in Beeston, Nottinghamshire · Covers Nationwide, across the UK Accreditation stated by provider: RICS, CIOB, Elmhurst, TrustMarkOwn websiteUK-wide
Energy Counsel
Based in Manchester, Greater Manchester · Covers Manchester, the North West and nationwide Accreditation stated by provider: CIBSE, BPEC, iATS, SITMA, BREEAM, AECB, ConstructionlineOwn websiteUK-wide
EnergyWise Services
Based in Belfast, Northern Ireland · Covers UK-wide (remote delivery available) Accreditation not yet checkedOwn websiteUK-wide
EPC Assess Ltd
Based in Midlands · Covers Birmingham, Wolverhampton, Coventry and UK-wide Accreditation not yet checkedOwn websiteUK-wide
kW Energy Consultants Ltd
Based in Ruddington, Nottingham · Covers East Midlands and nationwide Accreditation not yet checkedOwn websiteUK-wide
Litegreen
Based in Wrexham · Covers North Wales and the whole UK Accreditation stated by provider: TrustMark, Stroma, ECMKOwn websiteUK-wide
MES Building Solutions
Based in Newark, Nottinghamshire · Covers Throughout the UK (offices in Newark, London and Birmingham) Accreditation stated by provider: ATTMA, Elmhurst, AECB, TrustMarkOwn websiteUK-wide
Midland EPC
Based in Coventry · Covers Coventry and the Midlands, plus UK-wide Accreditation not yet checkedOwn websiteUK-wide
Purple Energy Solutions
Based in UK (several offices) · Covers Nationwide Accreditation stated by provider: ATTMA, UKASOwn websiteUK-wide
SEES
Based in Durley, Southampton, Hampshire · Covers UK-wide Accreditation stated by provider: Elmhurst, ATTMA, BREEAM licensed assessor company, Stroma certifiedOwn websiteUK-wide
StepSoft Coordination Services
Based in Oldham, Greater Manchester · Covers All ten Greater Manchester boroughs; also works across the UK Accreditation stated by provider: TrustMark, Elmhurst, ECMK, PAS 2035:2023Own websiteUK-wide
UK Building Compliance
Based in Hinckley, Leicestershire · Covers UK-wide (England, Wales, Scotland and Northern Ireland) Accreditation stated by provider: ATTMA, Elmhurst, SITMA, BPEC, UKASOwn websiteUK-wide
UK Energy Assessors
Based in Midlands · Covers East and West Midlands (nationwide network) Accreditation not yet checkedOwn websiteUK-wide
WRAP Retrofit
Based in Teddington, London · Covers UK-wide Accreditation stated by provider: RIBAOwn websiteUK-wide
Regional providers (check they cover your area) (1)
Ryan Hunter EPCs
Based in Newcastle upon Tyne · Covers North East, Northumberland, Newcastle, Gateshead and Durham Accreditation not yet checkedOwn website
What the assessment includes
- An energy assessment of the home (RdSAP)
- A condition report covering damp, ventilation and defects
- An occupancy assessment of how the household uses the home
- Significance and heritage checks where relevant
Where it fits in a retrofit project
The Retrofit Coordinator uses the assessment to build a medium-term improvement plan, a designer specifies the measures, and TrustMark-registered installers carry them out. The whole process is recorded and lodged so the work can be checked afterwards.
In Wales, Scotland and Northern Ireland
This guide describes the rules in England. Building regulations are devolved, so here is how retrofit assessment works in the rest of the UK.
Wales
Welsh Government schemes, including Warm Homes Nest, the Optimised Retrofit Programme and Green Homes Wales loans, use the PAS 2035 process. ECO4 also covers Wales until 31 December 2026.
Scotland
ECO4 uses PAS 2035 and covers Scotland until 31 December 2026. Home Energy Scotland grants and loans have their own rules, such as TrustMark or MCS installers and EPCs before and after the work, so check what your scheme asks for.
Northern Ireland
ECO doesn’t cover Northern Ireland, and current schemes such as NISEP and Affordable Warmth don’t require a PAS 2035 assessment. Some firms still offer one for privately funded projects.
Common questions
Do I need one if I pay for insulation myself?
Not always, but it is good practice and some lenders and installers ask for it. Funded schemes normally require it.
Is a retrofit assessment the same as an EPC?
No. It includes an energy assessment but also looks at the condition of the home and how it is used, which an EPC does not.
What does the assessment include?
An energy assessment of the home (RdSAP), a condition report covering damp, ventilation and defects, an occupancy assessment of how the household uses the home, and significance and heritage checks where relevant.
What happens after the assessment?
The Retrofit Coordinator uses it to build a medium-term improvement plan, a designer specifies the measures, and TrustMark-registered installers carry them out. The whole process is recorded and lodged so the work can be checked afterwards.
New to the jargon? See our glossary of terms, from air permeability to TrustMark.