PAS2035:2023 and BS 31010. Managing Risks in Retrofit Projects.

In the dynamic and fast changing world of building retrofit, managing risk is not

optional—it's essential. As buildings evolve to meet net-zero goals, energy efficiency standards, and regulatory requirements (such as PAS 2035), the complexity and potential pitfalls in retrofit projects grow exponentially.

Here’s where BS 31010 - the British Standard for Risk Management: Risk Assessment Techniques comes in. Though often overlooked, this standard plays a crucial role in ensuring that retrofit projects are not only effective but also safe, compliant, and cost-efficient. While PAS2035:2023 provides a framework for Retrofit Standards, the real value is in the referenced British Standards.

What is BS 31010?

BS 31010 provides guidance on risk assessment techniques used in decision-making, planning, and design decision. It supports ISO 31000, the international standard for risk management, and is used across various sectors - from construction and engineering to finance and healthcare.

In simple terms, BS 31010 helps you identify, analyse, evaluate, and manage risks systematically and transparently.

Why BS 31010 is important in Retrofit:

Retrofit projects are inherently risky. You're not working with a blank slate - you're upgrading existing buildings, often with unknown conditions, tight budgets, and strict regulations.

Here's why BS 31010 should be central to your retrofit risk strategy:

1. Supports PAS 2035 Compliance

PAS 2035 (the specification for domestic retrofit projects) requires a structured approach to risk management—particularly when identifying measures, coordinating roles, and managing unintended consequences like damp, overheating, or poor ventilation.

BS 31010 provides the framework and techniques to carry out this risk analysis in a consistent, documented, and auditable way and is specifically referenced in PAS2035:2023.

2. Help Avoid Costly Mistakes

Without proper risk assessment, retrofit projects can encounter:

• Unexpected structural issues

• Design failures (e.g., insulation causing condensation)

• Non-compliance with planning or building regulations

• Health and safety incidents on-site

BS 31010 encourages early-stage risk reviews that reduce rework, delays, and legal disputes.

3. Improves Decision-Making and Prioritisation

Retrofit projects often involve trade-offs: cost vs. benefit, short-term vs. long-term impact, thermal performance vs. heritage preservation. BS 31010 introduces techniques such as:

• SWIFT (Structured What-If Technique)

• FMEA (Failure Mode and Effects Analysis)

• Bow-Tie Diagrams

• Risk Matrices

These help stakeholders visualise and evaluate risks clearly—enabling better, evidence-based decisions. When used in conjunction with other standards such as BS:7913, retrofit professionals can avoid unintended consequences and reduce performance gaps.

4. Supports Health & Safety Requirements (CDM 2015)

Retrofit projects fall under the Construction (Design and Management) Regulations 2015 (CDM 2015). Proper risk assessment is critical here, especially when working in occupied homes or with vulnerable residents.

BS 31010 aligns with CDM principles by promoting preventative risk thinking at all stages—from planning to installation to maintenance.

5. Enables Transparent Communication Across Stakeholders

From the Retrofit Coordinator to installers, designers, and clients—everyone needs to understand potential risks and mitigation measures.

Using standardised techniques from BS 31010:

• Encourages a shared language around risk

• Improves documentation for audits and compliance

• Helps manage client expectations on performance and outcomes

Real-World Example: Risk in Wall Insulation

Retrofit Scenario: A social housing provider plans to retrofit 500 homes with internal wall insulation.

Without proper risk assessment:

• Moisture may be trapped inside the wall, leading to mould growth.

• Residents may face health issues, triggering complaints or legal action.

• The provider risks breaching PAS 2035 or TrustMark standards.

Using BS 31010 techniques:

• A HAZOP (Hazard and Operability Study) identifies moisture ingress points.

• FMEA highlights risks of thermal bridging in corner details.

• A clear action plan is developed: additional ventilation, damp-proof checks,

and resident engagement.

Result? A safer, smarter, and more compliant project.

When Should BS 31010 Be Applied in Retrofit?

You can (and should) apply risk assessment techniques at multiple stages of a retrofit project:

Stage: Purpose of Risk Assessment:

Initial Assessment Identify hidden building defects or resident vulnerabilities.

Design Stage Evaluate interactions between multiple retrofit measures.

Installation Planning Assess construction and safety risks

Handover & Monitoring Plan for ongoing performance risks (e.g., overheating)

In summary:

BS 31010 isn’t just a technical guideline—it’s a powerful toolkit that helps retrofit professionals navigate complexity with confidence. Whether you're a Retrofit Coordinator managing compliance, a designer planning measures, or a contractor delivering installations, embracing BS 31010 can significantly improve your project outcomes.

In an industry that’s rapidly moving towards quality, accountability, and whole-house thinking, structured risk management is no longer a ‘nice-to-have’—it’s a necessity. Looking to qualify as a Retrofit Coordinator? Does your training provider include a comprehensive guide to the most relevant BS standards as part of your study? If not, why not? They’re an integral part of the role of a Retrofit Coordinator in maintaining compliance with PAS2035 and Trustmark lodgement standards.

If you or your team are interested in our funded Retrofit Coordinator training courses, feel free to enquire here.