MVHR and building physics knowledge for healthy, comfortable and energy efficient homes
If you’re researching installing a Mechanical Ventilation with Heat Recovery (MVHR) system for your project, you may have heard of an Enthalpy heat exchanger or ERV (Energy Recovery Ventilation). But what is an “Enthalpy” heat exchanger? How does it change humidity in the home? And is it expensive to install? The basics of enthalpy heat … Read more
When we consider examples of good hygiene in our home, we may think of easy-to-clean materials, strong disinfectants and mops and buckets. But as Covid-19 is proving, hygiene in the home also relates significantly to the air we breathe indoors, and the bacterial and viral particles suspended within the air around us. There are many … Read more
If you’ve ever seen black mould in your home, you’re not alone. The problem with black mould is that unless it’s dealt with correctly (as I’ll explain below), it’s hazardous to health, not nice to look at – and will keep coming back. Mould is formed when a surface provides the right conditions for it to … Read more
Can an MVHR system help to cool your home in summer? Yes, a Mechanical Ventilation with Heat Recovery system (MVHR) can help to cool your home in summer, and it does it in a way that is quiet and automatic, using only the energy equivalent of two LED lightbulbs. This is the control panel of … Read more
Have you spent this summer struggling to sleep in the heat, unable to choose between the security and noise issues that come with opening your windows at night, or closing them and lying in bed sweating? You’re not alone. We often hear about how dangerous cold weather is for those suffering from fuel poverty in … Read more
I’ve written before about the average price of a high quality Mechanical Ventilation Heat Recovery (MVHR) installation, which includes an itemised price for each detailed ductwork layout, materials supply, installation and commissioning (airflow balancing and client handover). Today I’m going to explain (with photos) why the cheaper MVHR units are a false economy, and can … Read more
There’s a big problem in the plastic recycling industry. Oil companies are desperate to convince us that plastic recycling is possible, because it removes the guilt from us using so much of it in our daily lives. But in reality, there’s no such thing as plastic recycling. In the UK, we’ve made plastic recycling at home far too complicated. If you … Read more
30 years ago house-builders in the UK would have never considered how airtight they were building new homes. “Aren’t all homes fairly airtight, once you put the windows and doors in and pump the gaps with insulating foam?” Well, not necessarily. Fireplaces used to be for both heating and ventilation Traditionally, homes built before our … Read more
A Mechanical Ventilation with Heat Recovery (MVHR) ventilation system is a technology that requires pre-design before it can be installed into a home, office, school or boat. The MVHR may include any and all of the following schedule of services: Calculation of required boost airflow rate to meet or surpass Part F Building Regulations Sizing … Read more
The most common question I’m asked by people interested in mechanical ventilation with heat recovery (MVHR), low energy building design or Passivhaus is: How much space do we need for the ducts in an MVHR ventilation system? Variations to the question include: How big is the MVHR unit itself? How big are the ducts? Will … Read more