PAS 2035 Ventilation Requirements for Insulation Measures
The energy efficiency industry has recently seen a change in compliance and regulations for all installers wishing to undertake energy efficiency measures under Government and Utility funded grant schemes. This change from 1st July 2021 from PAS2030/2017 to PAS2035/2019 has seen the introduction of a Retrofit Assessment and the subsequent “Condition and Ventilation Strategy Survey”.
The reason for this change, is to ensure that no home is left with damp or condensation as a result of restricted ventilation. It is often the case that water vapour is created by everyday living and activities in the home such as breathing, perspiring, washing and drying of clothes, bathing, cooking, and burning fuels. When normal avenues of ventilation are restricted via the cavity walls or through the loft hatch, this can lead to a condensation build up on the walls and/or ceiling.
In order to prevent this, and assuming these are not already present, working satisfactorily or have the correct extraction rate; new extractor fans may need to be installed into any wet room, such as Kitchens, Bathrooms/Shower rooms. This provides a great opportunity for us to help you ensure that your property remains dry and well ventilated, and to give you the tools to maintain good indoor air quality all year round.
These extractor fans will either be fitted in place of existing units (if they are not sufficient) or if new, to the ceiling or through the walls by a fully qualified electrician. The final decision as to the exact location of each vent will be made on the day by the electrician. As part of the installation the electrician will remediate and make good where necessary.
If required, they will install a circuit breaker (mini-RCD) or bonding, as part of the minor electrical works. This is essential in order to prevent any failure and ensure that the work is done to the latest guidelines and regulations. The crucial part is that the fans need to be able to extract 60 Litres per second in Kitchens and 15 Litres per second in Bathrooms/Shower rooms.
Regarding other habitable rooms, such as Living/Dining rooms and Bedrooms, it is also important that there is sufficient ventilation within these rooms. From the ventilation survey, this may identify the need for further background ventilation, this can be by way of trickle vents in windows, or a room vent located in an external wall allowing a minimum of 5000mm2 of free air.
In some instances, there may also be the need for an additional undercut to be made to the bottom of the internal door to a room, to allow air flow whilst doors are closed. This will need to achieve an air flow of 7600mm2 “around a 10mm gap on a standard 760mm wide door”.
All additional ventilation requirements that have been stated within your retrofit design, which has been completed by a qualified Retrofit Coordinator, following the initial assessments, will need to be put in place prior to or alongside the installation of the insulation measure(s). In most cases, additional funding will be able to help with the costs.
We will discuss these ventilation requirements with you after our initial surveys and before the work gets booked for installation.
Frequently Asked Questions
- Why do I need additional ventilation when I already have some and open my windows?
To ensure properties are properly ventilated without relying on householders to act, research has led to a standard methodology that ensures sufficient ventilation is built in, resulting in a dry and healthy living environment. - Will my current extractor fans be sufficient?
They will be tested and checked for extraction rate and effectiveness. If they meet the requirements, they can be included as part of the ventilation strategy. - If I have a cooker hood in the kitchen, will this be sufficient?
It depends, as many cooker hoods only address odours and have limited effectiveness as extractors. Usually, an additional extractor fan would be needed. - Would a powerful bathroom extractor ventilate the rest of the upstairs rooms?
No, each wet or habitable room needs ventilation assessed on its own merits. - If I refuse ventilation, can I still have insulation installed?
You can, but not under any funding scheme provided by Utility companies (ECO – Energy Company Obligation) or the Government, as these make up the majority of funded initiatives.
For more information on domestic ventilation, refer to the Government’s ventilation guidelines.
Download PAS 2035 Ventilation Requirements Resource