BLANKET FILL INSULATION

Blanket fill insulation also known as a 'loft roll'. It helps to retain heat in your home which would typically escape through the ceiling. Blanket fill insulation usually comes in roolls and batts. While rolls can be unrolled into place, batts can be installed between rafters for even more effective insulation. It can be fit between studs, joists, and beams, and usually comes pre-measured to suit standard stud and joist spacing such as 400mm or 600mm centres. In its roll form, it can also be rolled over ceiling joists, which prevents heat from being lost via conduction. Blanket insulation can also be used as acoustical insulation for retrofitting warehouses and other such commercial buildings, as well as thermal insulation for areas inside the home (attic spaces). When used at ceiling level it is usually laid in two layers, with the first layer between the joists and the second layer over, and at right angles to the joists. It comes in various thicknesses available, including 100mm, 150mm, 200mm and 270mm. Blanket fill insulation is made by Celotex, Isover, Ursa, Knauf, Rockwool, Superglass and Thermafleece.

TYPES OF BLANKET FILL INSULATION

Generally speaking, blanket fill insulation can be divided into 3 main categories named as Mineral wool, Glass wool and Sheep's wool. Different ingredients are used in the production of these wool. In fact, 2 of them - mineral wool and glass woll are the same, they are just made up of different minerals. One is made of stone (stone wool) and rocks (rock wool) and the other is made of glass. Both of these insulation types operate on the insulating property of air trapped between the fibers. 

MINERAL WOOL

Mineral wool insulation is also referred to as stone wool or rock wool. It is made from a range of raw materials like rock and stone, and the process for this is very similar to the glass wool insulation process. Mineral wool is made by melting the raw material, which can be stone (such as basalt), at very high temperature, spinning it like cotton candy to produce very thin fibers, coating those fibers with a binder to hold them together, and forming it into the insulation batt or boardstock material to meet specific product needs. The mineral wool is then usually packed into either slabs, rolls, or batts. Mineral wool is highly fire resistant, which has long made it an insulation material of choice in many commercial buildings. Mineral wool is a heavier and more dense insulation material than fiberglass, giving it better sound-control properties and more effectively restricting air movement through it. The most popular stone wool manufacturer is Rockwool. Stone wool insulation is almost twice the price of fibreglass. Since stone wool is three times denser it is also heavier.

Products:

URSA 10 Diverso Loft Roll 

Rockwool Rollbatt

Rockwool Twinroll

Rockwool Roll

GLASS WOOL

Glass wool sometimes referred to as fibreglass insulation made of recycled glass fragments and pure sand. It is available in the shape of blankets or sheets. Being ‘made to measure’, the material’s extremely easy and efficient to install. Glass mineral wool is also breathable, helping to reduce the risk of condensation in the building. Glass wool can be supplied as either slabs or rolls depending on how the product will be handled and installed. Glass mineral wool is usually laid at ceiling level as a common loft insulation solution. It can also be fitted between rafters, as part of a loft conversion project, to provide both thermal and acoustic comfort.

Products:

Knauf Earthwool Loft Insulation Roll 44 Combi Cut

Knauf OmniFit Roll

Superglass Multi-Acoustic Partition Roll ǀ APR

ISOVER Spacesaver

SHEEP WOOL

Sheep's wool is a natural material obtained from sheep and other animals, including cashmere and mohair from goats. Because it is a natural fibre, sheep's wool insulation is also biodegradable, making it a more sustainable choice than synthetic insulation options. If you're looking for an environmentally-friendly way to insulate your ceiling, sheep's wool insulation is a great option. Wool insulation causes no issue to the health of people or the environment, it does not require any protective wearing while installation like fibreglass insulation. Sheep wool is nature's most effective insulator and has a crimped nature, which helps to form millions of tiny air pockets while packing or bonding wool fibre to trap air. The environmental benefits of sheep’s wool insulation are many. Each kg of natural fibre product locks up about 2-3 kg of carbon dioxide which helps remove CO2 from the atmosphere. Thermal Conductivity of sheep wool insulation is between 0.035-0.04 W/mK which makes sheep wool a better insulator. Sheep wool insulation can be used throughout the entire house from loft, floors, external walls and internal walls. Sheep wool will keep its insulation value even if moisture is present in the building. Sheep's wool is hygroscopic, so it can absorb around 25% of its own weight in moisture before its thermal efficiency drops. This ability to absorb water helps control humidity levels and reduces condensation within your home.

Products:

Thermafleece CosyWool

Thermafleece UltraWool

Thermafleece NatraHemp

MINERAL WOOL OR GLASS WOOL? WHICH ONE IS BETTER? 

Stone wool or rock wool (mineral wool) is stiff if it's compressed it just bounces back to its original shape. It has greater dimensional stability and lower thermal drift. Fibreglass (glass wool) on the other hand is fluffy. It does not maintain its shape either vertically in walls or horizontally in ceilings. So its thermal drift or loss of r-value over time is significant. The high density of stone wool equals more trapped air and better sound absorption properties than fibreglass. Stone wool insulation is naturally hydrophobic or waterproof because it is made of a basalt rock. The oils added to the fibers improve water repellency. Fibreglass on the other hand isn't waterproof. It can absorb water and moisture, become compacted and lose all insulating properties. The resistance to moisture means that stone wool doesn't promote rot, corrosion, fungi, mildew or bacterial growth unlike fibreglass. Stone wool is naturally fire resistant because it has a high melting point. Fibreglass is not as fire resistant and it will burn at some point. However, both products are easy to use. Stone wool can be cut with a stanley knife while fibreglass can be cut with a utility knife. Mineral wool is the better option for blocking sound from traveling through your walls and floors, as it is a much denser material than glass wool. It also helps prevent sound from leaving your home and disturbing your neighbours. When comparing the R-values of glass wool and mineral wool insulation, they both tend to have a thermal conductivity of around 0.044W/mK, so they are very similar in this regard. As it tends to be a lot easier to cut and fit into place, mineral wool is usually considered to be easier to install, which is important if you’re undertaking the task yourself rather than calling in a professional installer to help. Mineral wool is heavier and fits into place easier, while glass wool tends to be difficult to fit into certain spaces when you need it to. Glass wool is often cheaper than mineral wool by around 10%.
You must wear gloves, long-sleeved shirts when handling both these materials. If it touches your bare skin, tiny shards of rock or glass will be embedded in it and cause rashes. You must not inhale these fibers because they will be stuck in your lungs and may cause issues in the long run. Once they are installed however and hidden behind drywall, there isn't any risk to your health.

Video credit:https://www.youtube.com/watch?v=LTOtRysETpY&t=69s

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