Insulating the attic was a significant step in retaining heat in our home, further reducing the energy input needed to keep the house warm in the winter. Here, we strayed little from conventional building practices, except that we applied close to double the amount required by local code. Blown cellulose insulation is inexpensive – the material for this project cost less than $2000 – and the substantial decrease in heating costs quickly surpasses the slightly higher initial investment, both in economic and ecological terms.
Alexis, with his love and talent for restoring machines, couldn’t resist purchasing and reviving an old insulation blower, but various models are also available for rental. Blowing insulation is dusty and tiring work, but certainly possible to DIY. Alternately, this is a standard job that can be hired out to a contractor.
First, the rafters of the attic were marked at a height of 18 inches, which served as a guide for applying an even layer, providing over R50 worth of insulation. In comparison, the current recommendation for our region is R38, while many older homes have far less. Most homes are insulated with batting, which is significantly less effective than blown insulation despite claiming an equivalent R-value.
The narrow edges are the hardest to fill with insulation, but also make a significant difference in effectiveness. Beware that this is where hired contractors may cut corners — make sure that the insulation is blown the full reach of the attic.
We used cellulose insulation made from recycled newspaper. Cellulose insulation is often treated with pesticides and rodenticides — look for insulation without these additives as a more ecological option. Also take care to store the insulation out of the rain, and avoid using insulation that is moist to minimize clogging the machine.
Much gratitude to Debbie and Alexis, from Living Energy Farm, who persevered through several long, cold January days with an ornery machine to see this project through! Not to mention the many other steps of the renovation process…
magnoliacollective.org 