Applications of Different Insulation Materials

Insulation types and their applications vary depending where or what part of the house you need to install:

Bulk insulation materials

Mainly resists the transfer of conducted and convected heat, relying on pockets of trapped air within its structure. Its thermal resistance is essentially the same regardless of the direction of heat flow through it. Bulk insulation includes materials such as glass wool, wool, cellulose fibre, polyester and polystyrene. All bulk insulation products come with one material R-value for a given thickness. Bulk insulation traps air in still layers.

Reflective insulation materials

Mainly resists radiant heat flow due to its high reflectivity and low emissivity. It relies on the presence of an air layer of at least 25mm next to the shiny surface. The thermal resistance of reflective insulation varies with the direction of heat flow through it. Reflective insulation is usually shiny aluminum foil laminated onto paper or plastic and is available as sheets (sarking), concertina-type batts and multi-cell batts. Together these products are known as reflective foil laminates, or (RFL). Dust settling on the reflective surface greatly reduces performance. Face reflective surfaces downwards or keep them vertical. The anti-glare surface of single sided foil sarking should always face upwards or outwards. The total R-values for reflective insulation are supplied as ‘up’ and ‘down’ values. Total values depend on where and how the reflective insulation is installed. Make sure that system values provided by the manufacturer relate to your particular installation situation. Composite bulk and reflective materials are available that combine some features of both types. Examples include reflective foil faced blankets, foil backed batts and foil faced boards.

The building code sets out minimum requirements for the R-values of materials used in the construction of buildings. It is generally advisable to exceed these for greater comfort and energy savings. The higher the R-value, the better the thermal performance. Material R-values are supplied with bulk insulation materials and refer to the insulating value of the product alone. The higher the R-value the better the thermal performance. Total R-values are supplied with reflective insulation and depend on the product being installed as specified. R-values can differ depending on the direction of heat flow through the product. The difference is generally marginal for bulk insulation but can be pronounced for reflective insulation.

• ‘Up’ R-values describe resistance to heat flow upwards (winter R-values).
• ‘Down’ R-values describe resistance to heat flow downwards (summer R-values).

Up and down R-values should be quoted when installing reflective insulation in roofs, ceilings and floors. It is extremely important to ensure that your insulation is installed by competent, experienced professionals. Badly-installed insulation which is crammed in too tight, has gaps or gets wet will do little to protect your home, even if it's material with very high R-values. Also for using insulation materials, the walls and roof spaces also need to be constructed properly, using appropriate framing techniques, radiant barriers and other approaches to reducing heat transfer. And most importantly, insulate the foundations, basement walls and slabs, especially in colder climates.

Insulation Materials – Wide Choice

Basically, insulating materials are a compilation of materials, natural and man-made, that are now being used in insulating house and buildings in places where there are extreme swings of weather (extreme cold and extreme heat). All of these materials have been discovered (natural) and manufactured by man through existing technologies today.

All of these materials used to insulate places have their own individual characteristics that make each of them unique. Home builders and their installers use them according to the needs of the project, including the budget.

Also, not all materials for insulation can be used on all the house parts. Some are also chosen due to budgetary constraints. Aside from the listed familiar materials, there are still other uncommon materials (vermiculite, phenol foam, perlite and cementations) used in special insulation cases.

Fiberglass

Today, fiberglass tops the list of favorite materials used for insulation by home owners and home builder in the insulation business. This is made from fine glass fibers used in blankets (either batts or rolls), and as loose-fill.

In loose-fill, the molten glass is spun and blown into fibers using insulation-blowing machines. This is used in attic spaces and closed-cavity applications. They also come in as rigid boards and duct insulation.

Mineral Wool

There are two types of mineral wool, the rock wool made from natural minerals and slag wool made from the slag materials in blast furnaces. They are 75% recycled and do not need any chemicals to make them fire-resistant.

Both of these materials are usually manufactured into batts and rolls and as loose-fill insulation as well.

Cellulose

Recycled paper products (usually newsprint) end up as a very good insulation materials as cellulose. During their manufacture, the makers add borate (and sometime blend it with ammonium sulfate). Both of these processes make the finished product fire and insect resistant. 

This is usually the favorite choice used in new homes and in attic installations like the loose-fill. In addition, they are used as dense-packed filling in building cavities (these are usually the walls and the ceilings).

Plastic Fiber / cotton

The plastic fiber is made from recycled plastic (PET) bottles. The material is a fire-retardant; however, it melts when exposed to flames.

Cotton is made of 85% recycled cotton and 15% plastic fibers. It is treated with borate to repel insects. (Some makers use the trim wastes of recycled blue jeans.)

This is non-toxic and is also available in batts. A good environmental point is that it uses very minimal energy in its manufacture.

Sheep’s Wool / others

When used as insulation, this is treated with borate to work against insects, fire and molds. It can hold large quantities of water which is actually an advantage in walls. However, repeated wetting and drying can leach out the borate treatment.

Aside from the list, there are also other materials that are not common or familiar. This includes cementations and phenol foams, vermiculite and perlite.

There really are more insulation materials in development, made to fit the many types of insulation projects.  These are still in the pipeline in the makers’ R&D (research and development).

Insulation Materials – Choosing What’s Best

When insulating your house (if you are constructing one, or if you have bought a finished one that has inadequate insulation), you need to decide the right insulation materials that goes best with the right parts. (Different house parts have different insulation needs, and your installer/contractor can tell you the best for which part.)

As of today, there are so many available materials to choose from – ranging from man-made materials to organic that occur naturally in nature. However, you need to differentiate each one from the other. For qualities, they each have their pros and cons when using them to insulate parts of your house.

The present materials range in variety that includes bulky fiber materials (fiberglass, rock and slag wool, cellulose, natural fibers) to rigid foam boards to sleep foils. Again, each of these has its own advantage and features that will suit most everyone’s needs.

The following are some of the more popular ones (in terms of costs, flexibility, versatility, etc.)

Fiberglass

Top of the line is the popular fiberglass. It delivers, is good all-around choice and basically one of the most readily available among the materials. They are usually used in blankets (batts and rolls) and in loose-fill types.

They are also available in rigid boards, and duct insulation. The materials had been processed from recycled glass and made into fibers. The loose fill are used with insulation blowing machines (for attics and closed areas). They are also used in blown-in blankets.

Cellulose / plastic fiber

Cellulose is very familiar because it is processed from recycled paper (newsprint) with a high recyclable

material content (82 to 85%). It is manufactured into a fiber to have something that packs tightly into building cavities that will inhibit air flow. It also has a maximum R-value of 3.8 per inch. (Borate is added to make it insect-proof.)

Usually, this is used as loose-fill in open attic installations and is packed in building cavities like walls and cathedral ceilings. It is also blown dry into stapled netting on building cavities. 

Plastic fiber, on the other hand, is made from recycled milk bottles and formed into batt installations like the fiberglass. It is however treated with fire retardant and does not burn easily. It melts however when exposed to flame.

Mineral Wool

Mineral wool consists of rock wool and the slag wool. The rock wool is made from natural minerals like basalt. The slag wool is made from the slag of blast furnaces, those found on top of molten metal.

It has 75% post-industrial recycled content, with no chemicals added to make it fire resistant. The common use is in blankets (batts and rolls) and in loose-fill insulation.

Cotton / sheep’s wool

Many other natural fiber insulation materials are still in use, some of which are popular in other cold countries. The cotton insulation has 85% recycled cotton and 15% plastic fibers. It is treated with borate as fire retardant. Some are from recycled trim wastes from blue jeans manufacture.

Sheep wool is treated with borate for pests, fire, and mold resistance. As home owner, you can always confer with your installer which of these insulation materials is best for your needs.

Insulation Materials – What is Best for your Use

In colder countries of the world, people have discovered several ways to be comfortable in their homes using materials to heat them up. They have discovered the many insulation materials after so many years. Some are man-made, some are natural and some are hybrids. People chose what fits their needs.

The materials are as different as they all are from one another. The only likeness is that they all work the same way – preventing heat from moving around places, outside or inside, and keep things where they are needed. In houses and buildings, heat is conserved during winter, and is driven out during summer.

Insulators

Today, there are foam boards that are rigid and trap the air in controlling heat flow within a place. Reflective foils deflect radiant sun’s heat (resulting from the direct rays) to cool the living spaces.

Aside from these, there are several other materials that are very good in managing heart and cold in residences and buildings. (The not so popular insulation materials include vermiculite, phenolic foam, perlite and cementitious.)

The following popular materials (not in the order of consumer preference) have their own unique characteristics chosen by home owners and contractors. Their choices are all dictated by the present needs of the project, price, and some compromises.

Fiberglass

This is one the main favorites in insulation materials in that it delivers and that it is readily available. It is made from recycle glass and made into fibers used in blankets (batts and rolls) and as loose-fill. They are also used as rigid boards and duct insulation.

The loose fill are used with insulation-blowing machines (for attics and closed cavity applications). They are also used in blown-in blanket systems.

Mineral Wool

This other favorite has two types – rock wool and (man-made from natural minerals) and slag wool (made from by-products in blast furnaces). Both of these are 75% recycled. Also, they are fire-resistant.

These are usually made into batts and rolls as well as loose-fill insulation materials.

Cellulose

Basically, the materials are made from recycled newsprint paper. During the recycling proves, the makers usually put in borate, sometimes with ammonium sulfate, to make it fire and insect-resistant.

This material is usually the choice in new homes and in attic installations as loose-fill. The dense-packed filling is used in stuffing up cavities in walls and ceilings.

Plastic Fiber

Made from recycled plastic (PET) bottles, they are used as batt installation like the high-density fiberglass. It is treated with a fire retardant, although it melts when exposed to flame.

Compared to fiberglass, it is non-irritating to work with. As batts, they are slightly difficult to work, however.

Cotton

This insulation material is actually made of 85% recycled cotton and 15% plastic fibers treated with borate. (Some use the trimmed wastes from recycle blue jeans.)

It uses minimal energy to make because it is recycled. It is also non-toxic (it’s a natural fiber) and is available as batts.

Sheep’s Wool

These days, more materials are coming up to be manufactured into insulation materials. Some turn out to be good and some are failed experiments and discontinued.