Natural, Healthy, and Sustainable - The Green Insulation Guide

Insulating a home against air leaks and moisture intrusion is one of the most vital aspects of the construction process. Insulation plays a huge role in maximizing energy efficiency and preventing issues like mold and moisture or air penetration.

However, many types of insulation commonly used today are not considered natural or healthy. The most common types of insulation usually have some type of chemicals in them or are produced in such a way that has a negative net impact on the environment. Some types of insulation can have a negative impact on indoor air quality if they contain VOC's, flame retardants, or other carcinogenic chemicals. Thankfully, there are a variety of green insulation options that are much more in line with eco-friendly ideals.

A Guide to 7 Green Insulation Options

Insulating a home with sustainable insulation can be a lowkey selling point and add to the overall appeal of the home, as well as maximize energy efficiency.

Here is a guide to some of the best types:

1. Aerogel

Aerogel is a material that is made from 10% silica and 90% air. It is easily installed, and is available in both sheets and stickers. It is made by removing the liquid from silica and replacing it with air.

This process is done with both heat and pressure, neither of which are considered “dirty” methods of production, thus Aerogel is incredibly eco-friendly. Aerogel is mold-resistant, but is also one of the more expensive natural cavity wall insulation options. Aerogel is a newer product to the market and many of the long-term effects are still unknown. One thing that impacts installation nd handling is that it removes all your skin oil, which can be dangerous.

2. Polystyrene

Plastics generally do not make it into the eco-friendly category, but polystyrene is so energy efficient that some people might overlook the negative environmental impact. However, the high embodied carbon footprint of mineral wool manufacturing whose factories are fueled by coal and/or natural gas is another factor to take into account. Polystyrene actually comes in two forms — a spray that expands and hardens as it dries, and rigid foam boards which provide additional structural integrity for the walls. SPF should never be used as the primary air barrier. It shrinks and has pinholes if not installed properly. While SPF may be considered an air barrier by code and test results, it often doesn't function as one in real life. Unfortunately, polystyrene has a high carbon footprint and this carbon footprint lends to a less environmentally conscious assembly.

3. Icynene

Icynene is a type of spray foam made from castor oil. It massively expands and hardens after it’s sprayed. It expands so much that it completely seals off walls from any air leaks at all. It also cancels noise as well because of the near 100% coverage.

One of the main drawbacks of Icynene is actually in its main strength. It so thoroughly blocks out air leaks that you have to install a ventilation system to go along with it. This adds to the upfront installation cost quite a bit, but the monthly energy saving will eventually offset it. Similarly to Polystyrene, this material also has a high carbon footprint.

4. Sheep’s Wool

Sheep’s wool is one of the more expensive types of insulation, but it has many benefits as well. It’s fire retardant, for one. It’s also resistant to mold and can even help manage the moisture levels in a home by absorbing and releasing moisture as the humidity changes. It comes in batts just like fiberglass and is easily packed into wall cavities for an excellent natural home insulation option. Sheeps wool insulation is sustainable and renewable, but the carbon footprint of raising sheep should be taken into account when comparing healthy insulation options.

5. Denim/Cotton

Cotton and denim are derived from plants, making them incredibly natural and healthy as insulation options. These materials are shredded and spun into thick batts, which are packed into wall cavities.

As far as toxicity goes, this type of insulation is treated with a borate solution to add fire-retardant properties to it. It’s still considered eco-friendly despite this, though it’s one of the most expensive sustainable insulation materials. Include downside of denim insulation: Recently, the largest producer of denim insulation has been pulled from the shelves of Home Depot, as the company has shifted towards producing insulation for cold freight industries that ship perishable goods.

6. Cork

Cork is an excellent natural insulation option because it grows on trees and is easily harvested without any negative impact on the environment. Cork is free from toxins, recyclable, and renewable — it also cancels noise. Cork can be more expensive than many other insulation options though. It comes in rigid boards for installation.

Cork is not available in North America, so consumers often have to order internationally, which adds to the carbon footprint and cost of the product.

7. Hemp

Hempitecture HempWool® has a pressure-fit system that allows it to be easily cut and packed into wall cavities without any need for hazmat suits or special gear. It’s sold in panelized batts.

Hemp is safe to touch, non-irritable, and toxin-free. It is also resistant to pests, mold, mildew, and moisture.

Hempitecture HempWool® has a high thermal inertia year-round which helps keep homes cool in the summer and warm in the winter. Hemp insulation from Hempitecture is made from ~90% plant fibers and is biodegradable as a result. This material also has noise-suppressant properties.

Hemp Insulation is the Prefered Choice for Homebuilders

If you’re looking for a natural alternative to harmful insulation, look no further than hemp.

When it comes to cost-effectiveness, eco-friendliness, mold resistance, fire resistance, ease of installation, and insect resistance, it's clear that no other natural insulation options stack up against Hempitecture HempWool®. The material is both grown in America and manufactured in America, which means supply is consistently available.

Recent ASTM E84 tests on HempWool prototypes are showing a best-in-class fire resistance, achieving Class A fire resistance. This product will be available in 2023.

If you want the best healthy insulation option for a home, contact Hempitecture today to get in touch with an insulation specialist who can get you started.