MVHR and building physics knowledge for healthy, comfortable and energy efficient homes
It is subtle and understated in its impact on UK housing, but this new build bungalow home is one of the most energy efficient buildings in the world – and represents the future of housebuilding in the UK and Europe. We pressure tested the home this December using a calibrated airtightness testing fan and it … Read more
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
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
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
In my role as the lead MVHR technician at Heat, Space and Light Ltd we receive lots of questions and queries about MVHR systems. I’ve collected together my responses to some of the most pressing concerns that people have with a home ventilation duct system – from airborne spores to cleaning, maintenance, kitchen extraction and … Read more
When you have decided to specify a Mechanical Ventilation with Heat Recovery (MVHR) system for your home, it can quickly become confusing which type of ducting to use. There are two main types of MVHR ducting to choose from, explained below: MVHR ventilation ducting in a “branch” layout This is the classic ventilation system, also … Read more
Building Regulations Part F wants to know how much air (in m3hr) passes through each metre square area of the fabric (m2). This is the Air Permeability (AP or m3.hr/m2) figure of the building. To get the AP figure, one calculates the volume of air in the property. Then one calculates the total external envelope … Read more
Mechanical Ventilation with Heat Recovery systems (MVHR) are actually very straightforward to install yourself, as long as you’re reasonably handy with a drill and you aren’t afraid of heights. Here’s a step-by-step process for how to install your own MVHR or HRV system, safely, without leaks and saving a lot of money. If you’d like … Read more