Jill GoulderJill Goulder. June 2020

I’ve been an eco-house owner – part of the Lewes Eco Open Houses weekends – for the last 10 years. I’m happy to say that my house has been popular, largely because of high interest in the magnetic-strip secondary glazing which I’ve installed throughout: a cheap, effective and unobtrusive way of reducing heat loss through windows. I and my open-house assistants are always kept busy answering questions about it, and in 2015 it struck me that it would help both me and visitors if I made a video, answering the main questions. The idea was to encourage visitors intending to come to my house on an open weekend to watch the video first, so that they were ready-briefed before seeing the installation.

I’d looked around online for useful websites, and found almost nothing. I began to realise that magnetic-strip secondary glazing is an almost unmarketed product. It consists of 3 simple industrial ingredients; there is little margin on these products, and installation is largely a DIY job. The strip is only available online, and the acrylic is often bought online though we promote the useful local shop Brighton & Hove Plastics (https://www.brightonandhoveplastics.co.uk/). So there’s little incentive for manufacturers to promote the system, and very little information online on what it is, why it’s a very good idea, and how to install it.

So I recruited two colleagues: Neil Williams (who was at the time organising the Eco Open House weekends and who was a fan like me of mag-strip), and Olivier Sauer (our local expert on installation of mag-strip). None of us had made a video before; we used an iPhone and some borrowed editing software. The installation episodes had to be filmed live and with no second chances, as we only had two windows to use; a couple of glitches, but amazingly we (Olivier as cameraman, me and Neil starring) managed to produce enough footage for a 9-minute video. We were new to YouTube but duly posted our video there: https://www.youtube.com/watch?v=aEBbSkjkCik. It refers back to my own eco website about mag-strip, http://www.jillgoulder.plus.com/green/Magstrip.html.

And five years on, we have achieved 100,000 hits! and more than 200 comments and queries, worldwide. We’ve had a heartwarmingly large number of positive comments from viewers who were actively helped by our video. Some examples:

‘Very helpful and informative video. I am about to embark on using this secondary glazing in my house in Bristol… Much obliged to you!’

‘It was this video that convinced us to go ahead, as it made the installation seem so straightforward. [….] The house felt cosier immediately and the secondary glazing is hardly noticeable. I would recommend this approach to anyone.’

‘Very informative, helpful video. Makes so much sense!!! Thank you so much. On my way out to buy supplies for this project.’

‘Thank you for a helpful video. Also I would like to say as a foreigner I just adore your accents.’ 😊

‘I have a Grade 2 listed house so needed to find a solution that works within listing regulations and this definitely fits the bill. I’ve noticed a huge reduction in condensation (to pretty much none), warmer rooms and noise reduction benefits.’

‘Just a bit of extra feedback on how the sheets coped with the Beast from the East and Storm Emma. I’m near Taunton in Somerset in an exposed rural location and so had a real challenge the last two days. All the rooms with the sheets have been great, I had freezing rain to contend with and this did not affect any of the covered windows. I was insulated and cosy while the freezing rain and strong winds raged outside.’

‘Very interesting video. Thank you; I was going to buy some Velux thermal blinds but this system will be much cheaper and conserve more heat for my rooflights; I will be using it for all my windows.’

‘Superb and informative video, thank you for posting it. It’s just the no-nonsense video I was looking for for this project. A great solution.’

A few contributors offered tips that they’d found useful in installing it, and we had some queries, some but not all of which we could answer:

  • The extent of acoustic insulation (we are aware of a significant reduction in noise, but haven’t tested it formally)
  • Where to buy the steel and magnetic strips, in locations from Chile to Australia (they are a bit hard to find – googling needed)
  • The performance of the adhesive (we recommend investing in the highest-quality adhesive for the steel strip)
  • Deterioration over time (my answer: none for the acrylic sheet, sometimes steel strip needs reglueing)
  • Installing on large windows
  • Installing on windows with protrusions/ uneven frames etc

We’ve had virtually no negative comments, though we smiled wryly at one from a German:

‘In Germany we use double glazing since I can remember it. It is the standard. It keeps the place warm in the winter. And cool in the summer. [….] Also, it is better to seal the space between and fill with certain gases or leave it vacuum.’ (I responded to agree, but to mention that in the UK we have millions of draughty sash windows….)