Ventilation Testing, also called Extract Testing, is now a requirement for all new builds in the UK, as per Part F of the Building regs. The process involves evaluation of the mechanical air flow rates, taking things like trickle vents and extractor fans into account.

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Why are Ventilation Tests required in the UK?

It all boils down to the health of the building’s occupants. Builders have become comfortable with the requirements for achieving low air test scores, but this has increased the necessity to ensure correctly sized purpose ventilation systems are installed – which function as they should do. It’s all well and good to have a nice air-tight build which achieves a great air leakage score, but it needs to be properly ventilated or people will have breathing difficulties.

What’s more, if an extract unit is installed in a place where a lot of water vapour and pollutants are released, it needs to be removed to stop the spread to the rest of the building. Long-term impacts of dampness and mould can have serious effects on a person’s health, as we touched on in this article:build tight, ventilate right.

When to perform a
Ventilation Test?

Generally speaking, it’s best to perform a ventilation test at the same time as your air pressure or sound insulation testing, once power is available. There are a few ways you can help to achieve compliance with the regulations to avoid reruns and hold ups in the process. Before the test:​

  • Ensure that all trickle vents are installed correctly. Ideally, there should be one trickle vent per window and two for double windows
  • Ensure that all extractor fans and cooker hoods are functioning correctly – if they’re faulty, the testing becomes a lot more difficult​
  • Check that there is at least a 10mm undercut for each internal door

How do we perform Ventilation tests

We have a wealth of experience in all things relating to air quality and certification of new builds, and our experts keep things simple to get the job done.

We will start the process off by asking you or your architect to provide us with the full details of the ventilation systems, complete floor plans and the occupant schedule. Then, we will use unique calibrated equipment to measure the ventilation rate of the systems installed within the property. The building regulations have certain requirements, which are as follows:

  • All kitchen intermittent extractor fans must extract at least 30 litres of air per second. If an intermittent extractor fan in the kitchen is not adjacent to a hob, it must extract air at least 60L p/s.
  • All continuous extraction units in the kitchen must extract at least 13L of air p/s.
  • For bathrooms, the extraction rate of an intermittent extraction unit must extract at least 15L of air p/s, or 8L p/s for continuous extraction units.
  • Intermittent extraction units in utility rooms must extract at least 30L of air p/s, or at least 8L of air p/s for continuous extraction units.
  • The dwelling must have an adequate overall ventilation standard rate. This will depend on the number of bedrooms. Take for example, a one bedroom property requires an overall standard ventilation rate of 13L p/s. However, in five bedroom properties this rate must be 29L p/s for 5 bedroom properties.

Experienced Assessors

We have a wealth of experience in all things relating to air quality and certification of new builds, and our experts keep things simple to get the job done.

  • We offer practical advice before the test to give you the best possible chance of passing first-time.
  • Our services are nationwide, and our prices are more-than-competitive. We offer discounts for Ventilation testing when combined with air tightness testing, and in some cases we can even take care of both tests at the same time.
  • All of our engineers are CSCS certified, and use the highest-quality, calibrated equipment to ensure accuracy in results.
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If there is anything you feel unclear about or you simply want to speak to one of our team members, don’t hesitate to give our office a call.

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    Frequently Asked Questions

    If you’re unfortunate enough to be in the position where your building doesn’t pass, Purple Energy will help you to rectify the issues in the quickest and most cost effective way. Having said that, it’s best to avoid this, as it can be both time consuming and costly. The team here is dedicated to ensuring your building meets regulatory standards, so don’t be afraid to get in touch if you’re unsure about anything.

    Looking at Part F of the Building Regulations 2010, there are some takeaways. These are; (1) There shall be adequate means of ventilation provided for people in the building and (2) Fixed systems for mechanical ventilation and any associated controls must be commissioned by testing and adjusting as necessary to ensure that the objective referred to in sub-paragraph (1) is met. It’s worth noting that in point (1), the rules do not apply to a build or space within a building. This refers to places where people do not normally go, places used exclusively for storage, and a garage used in connection with a single dwelling.

    Part F of the Building Regulations provides guidance on building ventilation. Ventilation refers to the removal of ‘stale’ indoor air from a building and replacing it with fresh air, which is achieved by building air quality and preventing condensation in buildings.  In domestic properties ventilation there must be a continuous flow or air throughout the entire building. Extract ventilation is required in areas of increased humidity or pollution. The building must make it possible to carry out purge ventilation, which is the introduction of intermittent, rapid ventilation into a room—generally via open window or external door. The rules differ for non-domestic properties, though the continuous circulation of clear air is essential. This is possible through the use of an air conditioning system. Any air conditioning system installed must be accessible and maintained in order to reduce the risk of any potential airborne illnesses.