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This blog is one of a string describing ‘The Parka Wrap’ which was the name of a Master of Architecture (by Project) thesis through Unitec.

Retrofitting Insulation onto walls.

‘The Parka Wrap’, looks at externally insulating existing occupied buildings: Why do it. What to do. How to do it.

This project took place across 2020 and 2021. What got me annoyed the most in the process was discovering the acres of research that has been done for decades that points clearly at the effects of housing on health, but at the end of the day, nothing changes. It took me a while to figure this out, but I reckon it’s simple. Retrofitting walls with insulation is hard. So I came up with another option that’s not so hard.

We know why we should improve buildings. Improving buildings improves health. Respiratory healthcare alone costs the taxpayer $7,000,000,000 (that’s Seven Billion dollars) a year, and our houses contribute to this poor outcome. Couldn’t we focus this funding on better things like cancer research rather than repairing people affected by avoidable illness?

We are told the fix is easy – ‘fix leaks, add insulation, heat the house’ – that’s the ‘what’. But for 99% of the population fixing leaks in a building really is too hard – where on earth do you start? For most I think it would be the equivalent of being told to adjust the valve lash of bucket lifters. Say what? Yup, help is required.

Insulating a house sounds easy, but it’s 100% not easy to do it well, it’s costly, disruptive… and that gets to the final bit – heating. Heating an uninsulated building is a bit pointless unless you have lots of heaters and are made of money. However, if you insulate a home perfectly, you still need heaters, the heat doesn’t come from the insulation, and it doesn’t come from nowhere.

So we need another insulation option, and I’ve worked out a method of installing insulation on the outside of the existing wall, without massive amounts of waste, and with a measurable positive impact on the home’s ability to keep heat in. Is it free? No. New window, new cladding. Am I pretending it’s easy? No, but at least it’s not as crazy as ripping out the inside of the house to stuff some insulation inside the walls.

Result: Much better performance than a new house.

The next few blogs will unpack this idea further – the performance gains, the details for window install, the checks required as you plan, the product choices, install methods, structural considerations, and window flashings.