There is such a large difference because wood shavings have air pockets and solid wood may not have any: air is a better insulator therefore, the shavings will make a better insulator. a) Convection could not occur in solids because the particles would need to move away from each other and this cannot occur in solids.

radiation

A conductor is a material that allows internal (thermal) energy to be transmitted through it easily. Metals, such as copper and aluminium are the best conductors of heat. This is because metals have loosely held outer electrons surrounding the atoms called ‘free’ electrons.

1.4 per inch

Insulation acts as a barrier to keep heat in during winter and out during summer. Among the wide range of insulation products, cellulose has been used for centuries due to its raw material flexibility, low cost and recognised abilities to retain and release heat.

Increased insulation means a colder attic, which in turn means that any vapour escaping into the attic can condense before it can be vented. It is essential to air seal the attic to prevent moist indoor air from getting in. If there is no air and vapour barrier, concentrate on comprehensive air sealing.

But there may be a theoretical point of “too much.” If a home is over-insulated and is too tightly sealed, moisture can get trapped inside. Without proper ventilation, a home can build up too much moisture, especially in the attic (warm air rises), which can cause mold problems and, overall, lower indoor air quality.

Saving energy costs by preventing heat loss due to heat conduction. Preventing the roof from accumulating moisture damage. Ease of construction- insulating the ceiling can be easier than insulating the roof, particularly with older homes.

Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. Moisture buildup in the attic is a concern because it can condense into water, often causing mold. Good ventilation, from soffit vents and a ridge vent, will stop that.

Recommended insulation levels for retrofitting existing wood-framed buildings

The cost of roof insulation can depend on factors such as the type of insulation and your location. ServiceSeeking estimates that, on average, a full roof insulation project (including the installation) costs $22,000 but does state that costs can vary depending on the size of the job and materials used.

There is little learning curve involved with the application, and a DIY job will cost you about $500. Calling in the pros, on the other hand, will run you about $1,500 to $2,000 for an average 1500 square foot home.

The environmentalists in your family will likely favor it over the rolled kind of fiberglass insulation. Blown fiberglass insulation scores an R-value of 3.2 to 3.8, making it slightly less likely than rolled fiberglass to prevent the flow of heat into and out of your house.