Down is an exceptionally warm insulator, and weight-for-weight it’s often warmer than synthetic options. However, it doesn’t perform well when wet and can lose its insulating properties if not properly protected with a waterproof shell.
Some sleeping bags and jackets combine durable synthetic insulation with down to balance warmth, size, weight and water resistance. But which is more eco-friendly?
Eco-Friendly
Natural insulation products such as sheep’s wool, cellulose and cork offer numerous eco-friendly benefits. These include reducing waste, supporting local communities and using renewable materials that don’t require fossil fuels for production. They also have a lower embodied carbon footprint and sequestered biogenic carbon content compared to synthetic options.
These sustainable insulators are also free from harmful volatile organic compounds (VOCs) that can contribute to indoor air quality issues. They’re also typically fire, mold and moisture-resistant.
However, it’s important to note that not all green insulation is created equal. For instance, Rockwool is considered a “natural” product because it uses natural stone and recycled materials, but it’s produced with high-temperature melting processes that consume significant energy. In addition, the product’s performance can be questioned in areas with very hot or cold temperatures. Similarly, spray-in foams like Icynene are regarded as natural insulation but may not be appropriate for all locations. In these cases, homeowners should consider their sustainability goals and balance up-front costs with long-term energy savings.
Durability
While high-quality down is very durable when cared for properly, synthetic insulation is more resilient in wet conditions. It retains its loft even when wet and dries quickly, unlike down which can become waterlogged and lose its insulating ability. It is also less likely to cause cold spots in sleeping bags and jackets.
However, comparing the warmth-to-weight ratio of different synthetic insulations isn’t easy. Many brands will publish CLO values on their product spec sheets, but they’re often hard to find. This makes comparison difficult, especially for those looking for an ultralight layer.
Luckily, some green insulators are becoming more widely available. These include animal-based (like sheep’s wool) and plant-based (like hemp, cotton, cellulose, wood fibre and cork). Some of these products require energy to produce, but most of the raw materials are renewable and come from sustainable sources. These materials are also biodegradable and safe for installers to handle. This makes them a great choice for van conversions and new home (and tiny home) construction.
Breathability
A key factor to consider is breathability. Green insulation options like cellulose, hemp, cotton and jute are breathable, which means they keep you warm by trapping pockets of air next to your body rather than allowing cold air to penetrate and escape.
Another consideration is water resistance. With the introduction of DWR fabrics and hydrophobic down, many synthetic insulators now perform well even when wet. They also typically cost less than down jackets.
Regardless of the type of insulator you choose, it’s crucial to balance up-front costs with long-term energy savings and durability. Also remember that many insulators emit harmful chemicals into the indoor air, so choose a low-VOC option to avoid toxic off-gasing and allergens. Other factors to consider beach bag include the amount of energy needed to produce and transport conventional insulation materials, as well as their recyclability after use.
Cost
The initial cost of green insulation may be more expensive than synthetic options, but it will pay off in the long run with lower energy bills and greater environmental sustainability. Homeowners can weigh up-front costs against potential future savings to make the best decision for their project and budget.
One of the most common eco-friendly insulation types is cellulose, which is primarily made from recycled newspaper and other plant materials. It is available in loose-fill and dense-pack forms, which can be blown into open attic spaces or wall cavities using a specialized machine. It is treated with borate and ammonium phosphate to be fire-resistant and paraffin wax for moisture-resistance.
Synthetic down has a better warmth-to-weight ratio than synthetic insulation, but it loses its insulating properties when wet. Newer synthetic insulation, made from raw or recycled polyester, is able to retain its thermal performance even when wet and dries faster. It is also more breathable than down and performs well in humid conditions.
