PAS 2035 retrofit assessment
Retrofit assessments in Coventry and the Midlands
Before anyone insulates, re-heats or re-ventilates a home, PAS 2035 asks for a proper survey of the whole dwelling. Our Retrofit Assessors record the condition of the building, how it is lived in and how it performs, so that the plan which follows fits the home.
- Standard
- PAS 2035:2023
- The visit
- Typically 1 to 2 hours
- Method
- Non-invasive survey
- Registered with
- TrustMark
- Combine with
- An EPC in the same visit
Reviewed October 2026
What a retrofit assessment is
Retrofit means improving an existing home so that it is warmer, cheaper to run and healthier to live in. Done badly, it causes problems: insulation that traps moisture, new windows with no ventilation, a heating system sized for the house as it used to be.
PAS 2035 is the standard written to stop that happening. It grew out of the government-commissioned Each Home Counts review, and it treats the house as one system. The first step is always the same: a retrofit assessment, carried out by a qualified Retrofit Assessor before any work is specified.
How it differs from an EPC
| EPC | Retrofit assessment | |
|---|---|---|
| Purpose | Rates the home for a sale or letting | Gathers what is needed to plan improvements safely |
| Looks at | Construction, insulation, heating, lighting, glazing | All of that, plus condition, damp and mould, occupancy and ventilation |
| Result | An A to G rating and standard recommendations | A full data set and report for the Retrofit Coordinator |
| Carried out by | Domestic Energy Assessor | Retrofit Assessor, registered with TrustMark |
What we record
- The energy picture. The same measured survey that sits behind an EPC: construction, insulation, heating, hot water, glazing and lighting.
- Condition. Defects that should be put right before improvement work starts, including damp, mould, leaks and structural issues.
- Occupancy. How many people live in the home, how they heat it and anything about the household that the plan should allow for.
- Ventilation. What is already there, from trickle vents to extractor fans, and whether it is working.
- Construction and significance. Whether the building is of traditional construction or has heritage value, which changes what can safely be done to it.
- Plans and photographs. Measured floor plans and a photographic record of every element.
The survey is non-invasive and typically takes 1 to 2 hours. We need access to every room, the loft, and the heating and hot water systems.
When you need one
- Funded schemes. PAS 2035 has to be followed on publicly funded domestic retrofit, including the Warm Homes: Local Grant and the Warm Homes: Social Housing Fund. Every home needs an assessment before measures are designed.
- Landlords planning for band C. When several measures are on the table and £10,000 has to go a long way, a proper assessment stops you paying for work in the wrong order.
- Homeowners improving in stages. If you intend to insulate now and change the heating later, the assessment gives you a plan that still makes sense in ten years.
EPC and retrofit assessment in one visit
The two surveys share a large part of their data, so we can carry out both at once. It is our most requested combination: landlords get the certificate they need now and the information to plan what comes next, without a second appointment for the tenant.
What happens next
The assessment goes to a Retrofit Coordinator, who uses it to produce a medium-term improvement plan. PAS 2035:2023 requires one for every dwelling. It sets out which measures suit the home, in what order, and it can be delivered in stages over many years. Elmhurst Energy describes these plans as often covering 20 to 30 years.
We can hand the assessment to your own coordinator, or coordinate the project ourselves.
For installers and housing providers
We carry out assessments at volume for installers, housing associations and local authorities across the Midlands. You get consistent data, a clear photographic record and assessors who understand what the coordinator and the lodgement process need.
Sources: Elmhurst Energy guidance on PAS 2035 and on retrofitting homes; TrustMark; Elmhurst's summary of PAS 2035:2023 (July 2025), which became mandatory for new projects on 31 March 2025. This page is general guidance.
Where assessment fits
The five stages of a PAS 2035 retrofit.
Assessment
A Retrofit Assessor surveys the home and records its condition, occupancy, ventilation and energy performance.
Improvement plan
The Retrofit Coordinator turns the data into a plan for the whole home, which can be delivered in stages.
Design and quotes
Measures are specified and quotes are obtained from approved installers.
Installation
The work is carried out, with the coordinator checking that each measure goes in correctly.
Completion and checks
The finished work is checked against the standard, handed over and lodged with TrustMark.
Retrofit assessment questions
What to expect, before we arrive.
How is a retrofit assessment different from an EPC?
An EPC produces a rating. A retrofit assessment records much more: the condition of the building, signs of damp or mould, how the home is occupied and heated, and how it is ventilated. It exists so that improvements are planned for the whole house and not one measure at a time.
How long does it take?
Typically 1 to 2 hours for a single home. Allow a little longer if we are producing an EPC in the same visit, or for larger and older properties.
Is the survey invasive?
No. We look, measure, photograph and ask questions. Nothing is drilled or opened up.
When is a retrofit assessment required?
Whenever work is carried out under PAS 2035. That covers publicly funded schemes such as the Warm Homes: Local Grant and the Warm Homes: Social Housing Fund. It is also the sensible first step for privately funded work.
Who can carry one out?
A qualified Retrofit Assessor who is registered with TrustMark through an approved scheme. Ours are.
What do I receive?
The assessment data and report, which a Retrofit Coordinator uses to produce the improvement plan for the home. If we are coordinating your project, that step happens in-house.