Aipedia: Energy assessors and retrofit coordinators

AI in PAS 2035 retrofit assessments

Aipedia, by the Apex broking team · Last reviewed 2026-10-30

AI can draft PAS 2035 condition, occupancy and ventilation assessments, but the findings must come from the assessor's own site evidence. The coordinator relies on that assessment for risk decisions, so a generic report can lead to damp, mould and claims.

Part of: AI in energy assessors and retrofit coordinators

In short

Retrofit assessors use AI to turn site notes and photos into condition, occupancy and ventilation reports. The main risk is generic findings that miss property-specific defects, occupancy factors or ventilation problems. PAS 2035 sets the process, and TrustMark requires coordinators to be competent in risk assessment and to keep records and lodge data in the Data Warehouse. A wrong assessment can cause damp and mould after measures are installed. PI usually treats it as negligence, subject to the terms, with property damage and run-off points to check.

How retrofit assessors use AI

Under PAS 2035, the retrofit assessment gathers the information that the coordinator and designer rely on: the dwelling's condition, its occupancy and how it is used, its ventilation, and the energy assessment. Assessors use AI to turn site notes and photos into structured reports, draft condition descriptions, summarise occupancy interviews and populate templates.

That can save hours, but the assessment is the foundation for every later decision. If it is generic, everything built on it inherits the gap.

The duties that apply

The retrofit assessment sits within a defined process with clear responsibilities. The key points are:

PAS 2035:2023 sets out the assessment and the roles in the retrofit process; see the BSI overview.
The coordinator relies on the assessment for risk decisions, and under the TrustMark scheme requirements must be competent in risk assessment and building physics (Appendix 2).
Records must be kept as PAS 2035 specifies, with minimum information lodged in the TrustMark Data Warehouse.
Conflicts must be declared to the client and resolved where one person holds several roles, citing PAS 2035 6.1.5.
The energy assessment element is subject to reasonable care and skill under reg 24(1) of the EPB Regulations 2012 where an EPC is produced.

Our EPC and PAS 2035 rules map explains the framework.

What can go wrong

Generic assessments are the most common AI failure in retrofit, because they look complete. Watch for:

Template findings: condition text that could describe any similar house, with no property-specific defects.
Missed defects: existing damp, failed pointing, blocked vents or poor drainage left out because they were not in the prompt.
Occupancy gaps: drying laundry indoors, high occupancy or vulnerable occupants not recorded, though they affect moisture and ventilation.
Ventilation shortcuts: existing ventilation described as adequate without checking.
Lost evidence: photos and notes that support findings are not kept with the record.

Illustrative: an assessor uses an AI assistant to write up a condition assessment. The draft says the walls are in fair condition with no visible damp. In fact the site photos show staining at low level, which the assessor did not cross-check. The coordinator relies on the report, external insulation is installed and damp worsens. The homeowner claims against the coordinator, who in turn looks to the assessor.

The assessor's role and how PI usually responds

The coordinator makes the risk decisions, but on the assessor's information. If the assessment was wrong, a claim may be brought against the coordinator, the assessor or both, and insurers may seek contribution from each other. A claim that the assessment was negligent is usually treated as professional negligence under the assessor's PI, subject to the terms. Property damage exclusions, the limit and claims-made timing all matter because damp may appear years later; see run-off cover. TrustMark coordinators must hold PI and PL of at least £250k per property, or as required by the client. Read Does PI cover AI errors in EPCs and retrofit?.

Practical controls

Keep the assessment specific to the home. Controls that make a difference:

Write findings from your own site notes and photos, then use AI only to tidy the language.
Cross-check every AI condition statement against the photographs.
Record occupancy and ventilation observations explicitly, including anything unusual.
Flag uncertainty and items needing further investigation for the coordinator.
Keep evidence with the project record for audit.

Next steps in the process are covered in AI risk path and moisture risk decisions and AI medium-term improvement plans.

How Apex helps

Apex arranges PI for retrofit assessors and coordinators through our energy consultants PI service. A broker reviews how your cover responds to claims passed down from coordinators and to AI-assisted reports. See the AI in energy assessment hub.

Sources

Frequently asked

Can a retrofit assessment be written with AI?

AI can help structure and tidy the report, but findings must come from the assessor's own site observations and evidence. The coordinator relies on the assessment for risk decisions, so generic content can lead to unsuitable measures.

Who is liable if an assessment misses damp?

It depends on the facts. The coordinator may face the homeowner's claim but may look to the assessor if the assessment was wrong. Each party's PI may respond, subject to the terms.

What records must be kept for a retrofit assessment?

Records must be kept as PAS 2035 specifies, and minimum information must be lodged in the TrustMark Data Warehouse. Keep the photos and notes that support your findings so an audit can follow them.

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Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority. Registered in England and Wales, company number 07014570. This page is general information about how AI is used in the profession and how insurance may respond. It is not legal, regulatory or insurance advice on your circumstances, and it does not guarantee that cover will be available or on what terms.