Hemp Insulations facts
The lifecycle of hemp wool is a very appealing one from an environmental standpoint. Simply compare the manufacturing process; to produce a panel of hemp wool in the thickness needed to obtain a value of R10 requires 3.4 kWh of energy, while it takes 5.5 kWh to produce that value in cellulose, 15.6 kWh for mineral wool and 48.4 kWh for polyurethane*.
*Calculations by Denis Boyer, energy-efficiency coordinator for Ecohome.
For those wishing to reduce their impact during construction and renovations, it’s worthwhile to consider the embodied energy of products and remember that polyurethane requires an input of 14 times more energy to achieve the same thermal performance as hemp. And at the end of life, hemp insulation is reusable and/or recyclable, which is not the case for polyurethane.
Hemp wool has many other benefits when used as an insulation choice. It is non-toxic, it reduces sound transmission and it is very resistant to pests. Hemp is also vapour-permeable – meaning that moisture moves right through it. This allows hemp to help regulate the flow of vapour that results from differences in indoor and outdoor temperatures, which helps regulate the indoor climate and relative humidity of your home.
Denis Boyer also points out that a well-designed wall insulated with hemp has the advantage of allowing the drying not only of the moisture contained in the structural material at the time of construction, but also of the building envelope in the event of any moisture or water infiltration (infiltration from outside or leak from the inside).
Being a natural and non-toxic material ensures that installation is safer and easier than many other types of insulation with no special safety gear or gloves required.