Below are some examples where insulation is typically used not in the walls of the home:
On appliances - stoves and ovens, refrigerators and freezers, water heaters, water pipes, etc. Hence the reason you can have your oven on and still open the door if it without burning yourself.
On industrial applications. This is not as relevant to consumers looking for what insulation is best for their home.

When done properly, insulation can provide indoor comfort (by keeping your house cooler in the summer and warmer in the winter) and energy efficiency. So, when trying to decide what insulation is best remember that your goal is comfort and efficiency. If your insulation can meet those two objectives then it is best.

Determining and buying the insulation that is right for your household can be a challenge if you do not know where to start or what to consider. Below are some helpful hints on how to go about buying the perfect insulation for your home.

1. First you need to really consider what to insulate.

You must identify where the insulation will be installed or used, otherwise you can't pick the best insulation for that use. A personal inspection of your home may be sufficient, but it is still best to let the qualified people (such as your contractor) do the job.

Your house might need any or all of the following insulation:

-Wall/cavity wall insulation. Cavity wall insulation prevents your house from being exposed to rapid temperature changes outside. Studies show that heat loss due to un-insulated walls can reach as much as 50%, and cavity wall insulation could possibly prevent 70% of this from happening, thus making your more comfortable and keep your energy bills much much lower.

-Loft/roof insulation. Because hot air rises, heat loss through the roof can reach as much as 25%. This can be greatly reduced with proper attic or loft insulation. Many people think that they used bad insulation when in reality they just did not insulate enough. Insulating your ceiling is one of the best ways to make your home more energy efficient.

-Duct/pipe insulation. Leaky ducts or pipes can contribute to an increase in your heating (or cooling) costs. They can also burst (or freeze), so it is also important to have them properly insulated. You don't want to have to tear down walls to fix pipes because you neglected to properly insulate.

-Water cylinders/storage tanks. Hot water cylinders and cold water storage tanks also need to be insulated to prevent them from being exposed to intense cold or heat.

2. What to use.

Traditional insulating materials that are commonly-used in the households are the following:

-Fiberglass/fiberglass mats/mineral fiber. Fiberglass is the most common and versatile type of insulating material that is made from molten glass and spun into microfibers. It is usually pink or yellow in color, and comes in 3 forms, rolls, batts, and blown. Depending on where you put your insulation will depend on which type you use. Rolls are blankets of insulation that may or may not have vapor barriers, which prevent condensation in cold areas that could result in damage (such as mold). The best insulation has vapor barriers. Batts are similar to rolls but come in lengths ranging from 4 to 8 feet, thus are more manageable. Blown insulation is loose insulation that can be 'blown' into walls or ceilings. Sometimes it settles and after a few years it needs to be redone, but it is simple, and cost effective.

-Cellulose. This is a fibrous material made from scrap or recycled paper that is shredded and treated with chemicals that would make it resistant to fire and insects. It is then applied (poured or blown-in) into place, either as loose-fill or wet-sprayed with the use of a machine.

-Rock wool. As the name implies, rock wool is an insulating material that is made from rock. Manufactured similarly to that of a fiberglass (with molten rock replacing glass), rock wool can be in the form of a hollow brick or a porous concrete block.

-Synthetic insulation. Synthetic insulating materials are manufactured in several forms, some of which are the following:

Polystyrene foam - usually as rigid, pre-cut boards.

Polyurethane foam - usually as boards or foamed 'insitu' ("in position").

Spray-on expanding foam - similar to that found in aerosol cans, it can completey seal and insulate even the smallest areas in the house by 'poofing' up to as much as 2 to 4 times the original size when applied.

The following are suggestions of what insulation is best for the specific areas in your home:

For loft or roof insulation use: Mineral wool quilt, Blown mineral wool, or Blown cellulose fiber.

For duct or pipe insulation use: Mineral wool mat, Pre-formed split foam insulation, Foil-faced fiberglass insulation, Vinyl-faced insulation, or Ridged foam insulation

For wall insulation use: Blown-in cellulose, or Fiberglass (batt and roll) insulation

3. Check with an expert.

Aside from your personal considerations, the key to finding the best insulation for your home is to consult a professional.