New Zealand: Another Green Insulation Uses Hemp

By Susan Wilson, Blorge

One type of green insulation that you won’t find in the United States but will find in Europe and New Zealand is Hemp. Europe and New Zealand are allowing Hemp to be grown as a boost for local farmers since so many products can be made from it.

They allow what is called “industrial hemp” to be grown. This is a type “of low-narcotic hemp“.

We can’t grow it in the United States because too many government organizations get money from our “War on Drugs” which spends an inordinate amount of time catching small time marijuana growers. This is a shame since hemp is such a productive crop for farmers. This is an excellent crop that can be used for a myriad of legal purposes like making durable cloth, rope and now insulation.

Like sheep’s wool insulation, hemp insulation comes from a renewable resource. Just like sheep’s wool insulation, hemp insulation is biodegradable. It is also breathable - absorbing and releasing air moisture. It has excellent sound absorption and repels mold and insects.

Some hemp insulation is a combination of hemp and sheep’s wool. Other types have bi-component fibers, and soda for fire retardation. Still other kinds of hemp insulation use polyolefin or some other thermoplastic binder to keep the fiber together.

One of the most unusual and neatest environment features of hemp is its ability to “lock in” CO2 during growth. For every kilogram of hemp, 1.4 kilograms of CO2 is absorbed. Hemp is a totally natural product that not only helps insulate your home but also sequesters and breaks down CO2.

Hemp is stiffer than many other fiber insulations and doesn’t slump after it is installed. This is another type of insulation that does not require special clothing gloves or masks for installation. According to Natural Building Technologies(NBT), there are some limitations on where Hemp can be used.

NBT Hemp Batts can be used in loft spaces, between rafters and within walls and floors.

They are not however suitable for cavity wall insulation, or under ground floor slabs.

Very little energy is needed to produce hemp insulation. That along with its biodegradability, and CO2 absorption make it one of the greenest products on the market. But in order to use it here in the U.S., it would have to be imported (if allowed) which would ratchet up the price enormously. Too bad, it is a great product all around.