Retrofit Assessment Guide for Homeowners and Landlords
A Retrofit Assessment is the essential first step before any meaningful energy‑efficiency upgrade can begin. With rising energy costs and the UK’s drive toward net‑zero, more homeowners and landlords are turning to retrofit improvements to create warmer, healthier and more efficient homes.
Consider a Retrofit Assessment to be a highly detailed surveyor report with the inclusion of whole-house evaluation and consideration for energy performance and real-world occupancy.
🏠 A Whole‑House, Fabric‑First Approach
Unlike traditional energy assessments that focus on isolated features, a retrofit assessment looks at the entire building as a system. This is known as the Fabric First approach.
The priority is to reduce the property’s demand for heat and power by improving:
- Insulation (walls, floors, roofs)
- Airtightness
- Ventilation
- Thermal performance of windows and doors
Only once the building fabric is performing well do we consider upgrades to heating systems, renewable technologies or other building services. This ensures that any investment is long‑lasting, cost‑effective and compatible with future improvements.
A crucial part of this process is identifying existing defects—such as damp, mould, condensation, leaks or structural issues—that could undermine retrofit measures if left unresolved.
📋 What’s Included in a Retrofit Assessment
Before the assessment, your Retrofit Assessor may request helpful background information, such as:
- Approximate age of the property
- Details of extensions and any building regulation documentation
- Sign‑off documents for rooms in the roof
- Warranties or certificates for insulation, solar panels, boilers, fans or cylinders
- The last 12 months of gas and electricity bills
This information helps build an accurate picture of the property’s history, performance and retrofit potential.
A full retrofit assessment typically includes three core components:
🔎 1. Energy Performance Assessment (EPC)
As part of the assessment, an Energy Performance Certificate (EPC) is produced or updated. This is a legal requirement when selling or letting a property in the UK.
An EPC provides:
- An energy efficiency rating from A (most efficient) to G (least efficient)
- A breakdown of the property’s features and their performance
- Recommended measures to improve efficiency
- Estimated energy costs and potential savings
- Details of the accredited assessor
🏡 2. Condition Assessment
A condition assessment identifies any issues that could affect the success of retrofit works. This is an observational survey focusing on defects that may need repair before improvements are installed.
Typical issues recorded include:
- Damp, mould and condensation
- Cracks or structural movement
- Leaking gutters, downpipes or roofs
- Defective ventilation systems
- Poorly performing windows or extract fans
All findings are photographed, measured and documented. This ensures that any retrofit plan is safe, durable and compliant with PAS 2035 standards.
👥 3. Occupancy Assessment
Energy performance isn’t just about the building—it’s also about how it’s used.
During the occupancy assessment, the assessor will ask questions about:
- Heating patterns
- Hot water usage
- Ventilation habits
- Any comfort issues (cold rooms, draughts, condensation)
This helps tailor recommendations to the real‑world needs of the household.
🧩 Retrofit Assessment & Whole House Plan
Once all assessments are complete, the data is compiled into a comprehensive report using Stroma’s accredited software. This includes:
- EPC results
- Condition report
- Occupancy assessment
- Photographic evidence
- Measured data
- Recommendations for improvement
If you are working with a Retrofit Coordinator, they will use this information to create a Whole House Plan—a strategic roadmap that sequences improvements in the correct order.
This plan ensures:
- Measures complement each other
- Risks are managed
- Work is cost‑effective
- The property moves toward long‑term energy efficiency goals
Retrofit improvements can be completed room‑by‑room over time or as a full‑property upgrade, depending on budget and priorities.
🌱 Why Retrofit?
A well‑executed retrofit can deliver:
- Lower energy bills
- Reduced carbon emissions
- A warmer, healthier home
- Improved ventilation and air quality
- Increased property value
- Reduced risk of fuel poverty
With the right assessment and planning, retrofit becomes a smart, future‑proof investment.
🔧 How Building Compliance Testing Can Help
Our qualified Retrofit Assessors provide thorough, PAS 2035‑compliant assessments designed to give you clarity, confidence and a clear path forward. Whether you’re a homeowner, landlord or housing provider, we help you understand your property’s needs and make informed decisions about energy efficiency improvements.
Have a project in mind? Let’s get to work.
Need help with your retrofit renovation project or PAS-2035 compliance advice? Get in touch with our team today.