What is Retrofit?

To tackle climate change, newly built residential and commercial buildings must meet specific standards that aim to improve energy efficiency and minimise the carbon footprint of building projects. Promoting and installing sustainable technologies is part of the UK’s goal to hit a target of ‘net zero carbon emissions by 2050.

    Retrofit standards encompass various aspects of the building, such as ample ventilation, low air permeability, and renewable energy technologies. Retrofit is the process of promoting these kinds of building practices, with retrofit assessors delivering advice and consulting on projects to encourage these standards.

    In the case of existing dwellings built before the implementation of green regulatory standards, the PAS2035 was brought in to improve the energy efficiency of such buildings. Purple Energy offers quality, experienced retrofit assessors who complete onsite inspections and provide first-rate advice regarding new building projects and existing dwellings.

    What is PAS2035?

    PAS2035, which went live on the 1st of July 2021, offers a comprehensive framework for applying sustainable retrofit measures for existing buildings in the UK. The PAS2035 provides the best guide and conditions for low-energy retrofit projects.

    The specification for retrofit is designed to meet the requirements of government-endorsed quality schemes, such as the Energy Company Obligation (ECO), The Green Deal and The Green Homes Grant Local Authority Delivery (LAD). PAS2035 is applied jointly with its predecessor, PAS2030 (2019), which sets out the standards required for installing energy-efficient measures (EEMs).

    Where does PAS2035 apply?

    PAS2035 covers what is called ‘whole-house’ or ‘whole building’ retrofit. This approach to installing EEMs ensures technical demands are met, among other factors, including the comfort of occupants in the buildings.

    The specification’s goal is to assess domestic dwellings for energy retrofit. This is achieved by identifying areas for improvement and designing measures for applying the relevant solutions. It also focuses on the monitoring of domestic retrofit projects.


    Experienced Retrofit assessors

    Greener solutions are in high demand across all sectors. Over the years, Purple Energy has provided exemplary Retrofit assessments on buildings of all shapes and sizes. The team comprises industry experts and strives to achieve only the highest quality results for our clients. We aim to be efficient and effective with the work and deliver as promised.

    Frequently Asked Questions

    For any customers with additional queries regarding Retrofit assessments, we’ve answered some of the most popular questions below.

    The process of a retrofit assessment is broken down into four stages, which are as follows:

    • The retrofit Coordinator will complete a property risk assessment to establish a risk grade; A, B, or C. 
    • The Retrofit assessor will conduct the assessment and pass the findings to the coordinator.
    • Then, a retrofit designer will use the assessment to design relevant EEM improvements to the dwelling. 
    • Finally, these designs will be used to carry out the improvements to the property.

    Retrofit assessors ensure that projects comply with the PAS2035 document published by the UK government. The work includes a detailed assessment of the property and a report showing the findings.

    The average cost of a retrofit assessor can range from £120 – £240 during the initial retrofit assessment, with the work taking between 1-2 hours, depending on the size of the dwelling.

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