What could I do to reduce the temperature inside the building, so that I could work in the garage on sunny days? It was all a bit too hard, so I parked the project for a number of months until I could think through the processes required.
First attempt: install a rotary roof ventilator. Yes, it did reduce the temperature a little, but not enough.
Second attempt: paint the exterior of the roof white. Again, a modest reduction in temperature was achieved, but still not enough.
Third attempt: explore the possibilities of installing some form of insulation material under the roof without having to remove the roof sheeting to do so. A number of options were explored, however many options were cost prohibitive. Parking the project up for a few more months allowed me to consider some unusual options. During my working career I had a dealer who kept his workshop cool by spraying water onto the roof of the workshop. The water was recovered into a large storage tank and a pressure pump recycled it in a volume that allowed the water to cool in the tank before being resprayed on the roof. The system worked fine until there were a series of exceptionally hot days and the water would not cool sufficiently to provide the required cooling effect on the workshop roof. The cost of installing such a system on my garage roof would prove to be cost prohibitive.
Having restored a number of cars and trucks over the years, my next thought was to cover the underside of the roof with automotive sound deadening and heat reduction material. This material is a three layer product with aluminium reflective sheet on the face, a ten millimetre thick foam centre layer, and then an adhesive layer. This product can be found on the underbody of most cars and is normally used under the bonnet and boot lids and inside the doors to reduce heat and noise in the passenger compartment.
The next step was to locate a suitably sized product that could be used on the shed. A product was located and other than some minor trimming, was in a size that could be installed with a minimum of fuss. Well, maybe not a minimum!
How do I install this product on my own and still have the sheets aligned correctly to the roof?
An installation process was then developed. Firstly, I needed to align the cut sheet to the underside of the roof panels. It was impossible for one person to install the two and three metre long sheets with the entire adhesive protection layer removed, and have them aligned correctly. Light bulb moment, use 10mm thick bamboo plant stakes to hold the sheet, with the adhesive protective layer in place, and position the sheet in the required location. The next step was to lower the first one metre of the insulation and remove the adhesive protective backing from the sheet and then stick the insulation to the roof. A paint roller on an extension pole ensured that the entire adhesive surface made contact with the underside of the roof. The process was to then lower the insulation one metre at a time and repeat the process, until all of the insulation was attached to the roof. Just to ensure that the insulation stays put, I reinserted the bamboo garden stakes.
Barry O’Connor.
28 March 2021.