Cavity wall insulation is an economical and energy-saving way to insulate your home, saving money as well as decreasing its carbon footprint.
Insulation can be added to cavity walls by injection with either a hose or gun from a company that specializes in this technique, with three main materials that may be injected:
Polyurethane Foam
Polyurethane foam insulation is an economical and flexible material suitable for wall cavity insulation applications, offering great thermal insulating properties due to its closed-cell structure and cell gases which resist heat transfer. Furthermore, flame bonding processes make this versatile material even more suitable.
Closed-cell polyurethane foam insulation material can provide R-values comparable to those achieved through installing cellulose or mineral wool into cavity walls, and also serve as an air seal that enhances efficiency while eliminating cold spots in buildings. It is sprayed directly onto walls to create an excellent air seal for added efficiency and reduced cold spots in a building.
Injected polyurethane foam cavity insulation can be an ideal choice for difficult-to-treat housing situations such as narrow or stone cavities and failing brick or timber frame wall ties. BUFCA installer network offers a 25 year insurance warranty on domestic injected polyurethane foam cavity wall insulation products installed, providing homeowners with peace of mind.
Cellulose
Cellulose is one of the most abundant natural polysaccharides. Similar to chitin, which consists of N-acetyl D-glucosamine monomers bonded together into polymers by hydrogen bonds, cellulose boasts hydroxyl groups on each monomer that allows it to hydrogen bond with other molecules for hydrogen bonding, giving strength and rigidity to plant fibers, algae, fungi, bacteria, tunicates shells as well as coral reef structures.
Wall cavity insulation is also commonly used in new construction and renovation applications, often as loose fill in attics, dry spray in walls and wet spray for new builds. Professional installers utilize various methods of installation: loose fill in attics, dry spray for walls and wet spray for new builds.
Loose-fill cellulose insulation can be installed before or after drywall installation using a special fill tube, with one application using either method taking between one to four hours per stud plug to install densely packed cellulose for an R-value up to R-3.8 per inch. However, since loose-fill insulation tends to slump over time it should always be done professionally by a trained installer.
Mineral Wool
Mineral wool insulation has long been used in UK homes, yet improper installation may lead to issues. Finding an experienced contractor to install your wall cavity insulation could help alleviate potential complications.
Mineral or stone wool is produced by spinning together molten glass, natural rock and industrial waste into yarn. It serves as an asbestos replacement after it was banned as dangerous in 1900.
Mineral wool insulation’s open-cell structure traps air and forms an effective barrier that stops convection while decreasing thermal conductivity, making it fire-resistant. Available in varying densities to achieve various thermal properties and supplied either loose granular form, batts for blown insulation or rolls – this insulation material often works in combination with other insulation materials like cellulose or foam for more complete solutions.
Polystyrene Beads
As their name implies, these tiny balls of polystyrene combined with binding agents or PVA adhesive are blown into your cavity wall to add insulation. Their low water absorption rate means they won’t transfer moisture between walls that could lead to damp issues.
Plastic insulation panels are made of plastic, but unlike single use plastics which cause environmental problems, these do not break down, meaning they will outlive your home and remain intact for its life span. Furthermore, these products boast high thermal projection rates and offer better lambda values than mineral fibre options.
EPS insulation requires a clean and spacious cavity in which to fit, making it more expensive than other forms of insulation; approximately PS10-15 per square metre including labour costs. However, its benefits outweigh this drawback and save you money on heating bills while being eco-friendly product.