Read Our Blog

Mon Nov 17, 2014



Our home is our sanctuary and where we want to feel the most comfortable. But comfort isn’t simply about having plump pillows and thick, luscious carpets, lovely as they are. The level of humidity in the indoor environment is massively important to our overall comfort and wellbeing. We’ll be posting a series of blogs in the coming weeks that look at the issue of comfort in the home and here, in the first of the series, we’ve decided to focus on human hair and why, curiously, it is a good indicator of the level of humidity in your property.

Here’s some techno jargon to explain how…

Instruments that measure moisture content in the atmosphere are called hygrometers, and one of the early models was a “hair tension hygrometer”, which worked on the principle that human or animal hair absorbs moisture from the atmosphere and changes in length. Humid air causes hydrogen bonds to form between water molecules and the proteins in your hair, triggering curls and frizz – which is why a holiday in a humid climate can cause frustration for anyone wanting to show off their newly coiffured locks!

In a hair tension hygrometer, a strand or braid of hair eight to ten inches long is fastened to a screw at one end and then connected to a simple pulley which moves over a graduated scale to indicate changes in relative humidity (RH) inside the home.

Still can’t picture it?

The traditional Swiss weather houses, often designed in the shape of an Alpine chalet, also work on this concept. You must have seen them! A typical model has two doors - the left door has a girl or woman, the right side a boy or man. The female figure comes out of the house when the weather is sunny and dry, while the male comes out to indicate rain. The male and female figures ride on a balance bar, which is suspended by a piece of hair or catgut. The hair relaxes or shrinks based on the RH in the surrounding air, relaxing when the air is wet and tensing when the air is dry. This action swings one figure or the other out of the house depending on the humidity.

So, we can tell that there’s humidity in the air…..what can we do about it?

Well, humidity is caused by a number of different factors including human activity and weather conditions.  The optimal level of RH in a British home is between 40 and 60% which is why it’s important that, in airtight homes, airflow is circulated throughout the home at all times. On average, we spend over 70% of our lives in enclosed buildings which makes the need for improved indoor air quality more important than ever. An effective ventilation system ensures the fabric of the building and its residents are protected against the harmful effects of high humidity which include mould growth, dust mites, asthma and summer overheating. 





More news items

How a year in the ventilation industry triggered my addiction to good quality air.

Ventilation matters

Sat Nov 29, 2014

As a Product Marketing Manager, my key objective – my ‘raison d’être’, if you will – is to get excited about my products. A good product marketer should be able to muster enthusiasm about anything. I’ve managed it in the past with ...

Continue Reading →
Wilmcote House, Portsmouth

Latest News | Zehnder MVHR units installed in UK’s first EuroPHit project

Thu May 21, 2015

Progress is being made at the UK’s first EuroPHit case study project, Wilmcote House, a 111 unit development located in Portsmouth that is being funded by ...

Continue Reading →