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Why Consider Natural Wool Insulation?

Trying to keep your home warm in the winter and cool in the summer is and should be the goal when choosing insulation. But how do you know which type of insulation to choose while still being environmentally conscious? This article will help you understand how natural wool insulation may be the right choice for you.


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There are, of course, many types of insulation to choose from which can make the selection process difficult. The biggest difference however in the types of insulation is what materials are used to make the insulation.


Let's Start at the Beginning

Insulation can be made from a variety of material including plastic foam, loose fill, rigid board and some can even be sprayed right into the walls of your home. The most common types of insulation are usually made from materials like plastic, polystyrene fibers, fiberglass and mineral wool.


Insulation effectiveness is based on what is commonly referred to as "R value". The R-value is a measure of insulation's heat loss, therefore the higher the R-value, the greater the insulation value.


Sheep wool is a natural insulator because it has a crimped nature which traps air in millions of tiny pockets. Sheep wool insulation has an R-value of approximately 3.5 to 3.8 per inch of material thickness, 0.3 to 0.6 points higher than fiberglass, cellulose, or mineral wool.


Whether you are a do-it-yourselfer or you hire a professional, there are important things to consider about the actual insulation process. One of the issues you need to be aware of when it comes to fiberglass insulation, is the potential for skin irritation and skin allergies. Proper clothing and protective gear is a must when installing fiberglass.


For this reason among others, many people choose natural sheep wool insulation. Wool is not irritating to the respiratory system or the skin like fiberglass and some other alternative insulating materials.

More About Wool in General

Wool’s unique fiber properties cannot be synthetically duplicated, making it one of nature's most amazing fibers.


First, wool is resistant to fire. It will burn if it's held to an intense fire, but when it's removed from the flame, it will self-extinguish. The reason, in part, is that each and every wool fiber contains moisture.


Wool is also an incredibly flexible and durable fiber; one fiber can be bent back more than 20,000 times without breaking and is said to be comparatively stronger than steel. To put this in perspective, a cotton fiber can only be bent 3,000 times before it breaks. Wool's natural elasticity makes it resistant to tearing as well. Wool fibers can be stretched as much as 50 percent of their original length when it's wet and about 30 percent when dry.


In addition, wool is also resistant to mold and mildew. It's no wonder humans domesticated sheep in 8000 B.C.


Wool is Also a "Smart" Insulator


Think of it like a thermos for your body; it can keep you warm or cool depending on your needs. It keeps you warm without overheating your body.


In the Sahara Desert, Bedouins wear thin wool to keep them cool in the searing heat. The secret to both of these facts are the tiny pockets of air in wool that provide both insulation and breathability.


Wool is also able to soak up as much as 30 percent of its own weight in moisture without feeling wet, which is one of the reasons it can still keep you warm even in the rain. The fibers have a natural crimp that helps to wick moisture away from the body. Getting this moisture off your bare skin is a key element to keeping warm in wet conditions.


Wool actually absorbs water from both your skin and the atmosphere around you to create a dry and warm environment where it counts -- against your body. So the next time you pass a flock of sheep standing around in the pouring rain and wonder why they don't get out of the rain, remember the complexity of their protective coat.

The Science of Wool

But there are other more complex elements to the wool fiber. Wool can soak up a lot of moisture and is a "hygroscopic insulator". The crimp in the wool fiber forces each strand to bump up against each other, as opposed to lining up side by side or laying down flat together. This keeps the tiny air pockets intact, acting as little insulators -- the key to being able to keep you both warm and cool.


Air has the ability to move heat by convection -- in other words, by moving and circulating. Through convection, air can transport heat from one place to another. When air is contained in very small pockets, it cannot circulate easily, so heat is retained. This same process works for cold.


Think Styrofoam cooler -- the Styrofoam's tiny pockets of air act as an insulator for heat or cold (depending on what's inside the cooler). The same concept goes for wool.


The combination of the fiber's natural crimp and the chemical and physical processes that take place when wool meets moisture make it the best all-season natural insulator on Earth.

12 Advantages of Natural Wool Insulation

1 -- Fire and Vermin Resistance -- Even though wool is naturally fire resistant, newer proprietary processes chemically bond a naturally occurring element to provide even more flame resistance as well as a vermin repellant to the wool fiber.
2 -- Versatility -- Natural wool insulation can be used in every facet of the building industry; including new and existing residential structures, commercial, industrial, and institutional facilities.
3 -- Consumer Value -- Wool insulation has long offered excellent value/return on investment for buyers due to its ease of installation, proven performance, and energy savings.
4 -- Non-Toxic -- Recent toxicologist studies demonstrate no observed adverse health problems associated with natural wool insulation.
5 -- Continued Performance -- Natural wool insulation does not breakdown over time in terms of fire resistance, moisture absorption, mold growth, corrosive action or degradation.
6 -- Acceptance by Officials -- Natural wool insulation has passed stringent testing and meets building codes.
7 -- Resists Mold Growth -- Wool insulation contains borate molecules that resist spore propagation.
8 -- Acoustically Superior -- Wool is an effective sound control material.
9 -- A Naturally "Green" and Energy Saving Product -- Some providers are able to use wool not suitable for the textile industry and therefore usually relegated to landfill or other disposal. The manufacture of natural wool insulation uses less than one-tenth the energy it takes to manufacture fiberglass insulation or rock wool. Natural wool insulation provides an additional benefit in reducing heating and cooling costs, by eliminating voids and air pockets common with other insulation materials, reducing air infiltration and increasing the "Effective R-value" of the wall assembly. Natural wool insulation also helps control sound. It has superior thermal properties, and is environmentally friendly, even in the manufacturing process.

10 -- Sustainable -- High quality natural wool is 100% recyclable and of course self sustaining in that sheep grow a new crop automatically every year.
11 -- Installation Safety -- Natural wool insulation requires no safety equipment for its installation. Since all the components are 100% natural, there is no need for breathing nor eye protection, you don’t even have to wear gloves!
12 -- Doesn't Settle -- Many forms of loose insulation settle over time, resulting in air gaps and spaces that seriously reduce the effective insulation capability. The naturally occurring “pliable memory” of wool fiber eliminates settling. Wool also actually expands to fill every space completely. This results in improved long-term thermal effectiveness by as much as 20%.


(The views of the authors or originators expressed herein do not necessarily state or reflect those of HHI: its principals, executives, board members, advisors or affiliates.)


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Why Consider Natural Wool Insulation?:  Created on January 19th, 2011.  Last Modified on June 19th, 2011


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About Bob Workman

Bob Workman represents Oregon Shepherd, a leading natural sheep wool insulation producer. Consumers can download a free copy of “12 Reasons to Choose Natural Wool Insulation” at the Oregon Shepherd website.





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