GQA Level 4 Diploma in Retrofit Assessor

GQA-QUALIFICATIONS-LIMITED

vocational

This subtopic equips learners with the skills to use advanced software for simulating energy use and ventilation in existing dwellings, crucial for retrofit planning. It covers inputting building data, interpreting results, and predicting the impact of retrofit measures on both energy efficiency and indoor air quality. The modelling outputs directly inform decision-making to ensure compliance with the PAS 2035/2030 framework, enabling whole-house assessments that balance thermal performance with adequate ventilation.

Objectives

Exam Tips

Pitfalls

Key Terms

Mark Points

What You Need to Demonstrate

Key skills and knowledge for this topic

Award credit for accurately setting up a baseline model of an existing dwelling, including correct input of construction types, U-values, air permeability, and occupancy profiles.
Demonstrate competence by performing at least two retrofit scenarios, comparing predicted energy savings (kWh/year) and ventilation effectiveness (e.g., air exchange rates) against the baseline.
Provide clear evidence of using modelling outputs to assess compliance with PAS 2035 ventilation requirements, such as identifying risk of under-ventilation post-retrofit.
Show the ability to justify specification choices (e.g., insulation levels, MVHR selection) based on modelled impact, cost-effectiveness, and moisture control.

Marking Points

Key points examiners look for in your answers

Award credit for accurately setting up a baseline model of an existing dwelling, including correct input of construction types, U-values, air permeability, and occupancy profiles.
Demonstrate competence by performing at least two retrofit scenarios, comparing predicted energy savings (kWh/year) and ventilation effectiveness (e.g., air exchange rates) against the baseline.
Provide clear evidence of using modelling outputs to assess compliance with PAS 2035 ventilation requirements, such as identifying risk of under-ventilation post-retrofit.
Show the ability to justify specification choices (e.g., insulation levels, MVHR selection) based on modelled impact, cost-effectiveness, and moisture control.

Examiner Tips

Expert advice for maximising your marks

💡When presenting evidence, always include a justification for the software chosen (e.g., SAP, PHPP, dynamic simulation) and any limitations acknowledged.
💡Focus on the 'whole-house' approach: show how energy and ventilation are interdependent and how you balanced these in the retrofit plan.
💡Use the PAS 2035 Risk Assessment template to structure your modelling findings, clearly mapping each hazard to a mitigation measure.
💡Practice sensitivity analysis: demonstrate how varying input parameters (e.g., occupancy, climate data) affects outcomes, and explain how you accounted for uncertainties.

Common Mistakes

Pitfalls to avoid in your exam answers

Failing to calibrate the model with actual energy bills or air permeability test results, leading to inaccurate baseline predictions.
Overlooking internal gains and thermal bridging in the energy model, resulting in underestimated heating demand.
Assuming that adding insulation alone solves all problems without modelling the increased risk of condensation and poor ventilation.
Misinterpreting ventilation modelling outputs, such as confusing air changes per hour with equivalent area, leading to non-compliant specifications.

Key Terminology

Essential terms to know

1. Introduction to energy and ventilation modelling software2. Simulating energy use and ventilation performance in existing dwellings3. Predicting the impact of retrofit measures on both energy and ventilation performance4. Use of simulation in planning, decision-making, and ensuring compliance with ventilation and energy standards as per the most current version of the PAS Retrofit Standards Framework

Ready to test yourself?

Practice questions tailored to this topic

GQA Level 4 Diploma in Retrofit Assessor

What You Need to Demonstrate

Marking Points

Examiner Tips

Common Mistakes

Key Terminology

Ready to test yourself?

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