Every house in Australia should be externally wrapped with an aluminium anti-glare foil, in both walls and roofs. An anti-glare sarking foil wrap around walls and a Concertina Foil Batt stapled to the sides of the studs will improve the overall insulation of a clad wall to R2.2 and a brick veneer wall to R2.4.
Framed walls consist of 90 mm timber studs and typically R1.5 fibrous batts are fitted into cavities, entirely filling them and pushing up against the foil wrap, destroying the foil's insulating efficiency.
The Concertina Foil Batt system divides the 90mm airspace into two reflective airspaces, similar to the thermos flask principle with no contact to external foil. Foil Batts can not slump or absorb moisture and they provide more space for electrical cabling, water and gas lines.
For energy efficient design, Foil Batts are the best insulation as they can not slump, cause condensation build-up or absorb or retain or conduct heat or moisture. Costing less than standard fibrous batts they are non-irritant, compact and thermally efficient. Foil Batts are the easiest DIY insulation and can be installed in ceilings, roofs, walls and floors for new and existing homes.
Concertina Foil Batts create a multiple reflective airspace in the 90mm wall frame preventing summer radiant heat flow to be conducted inward and reverse reflects winter radiant heat flow to be conducted out. Concertina Foil Batts do not cover electrical cabling and other services.
Autex Polyester Greenstuf Batts (Wall Batts R1.5, R2.0 and R2.5 90mm products) Greenstuf batts are a non-itch, non-irritant fibrous batt to fit in the standard 90mm external wall construction frame.
CAUTIONARY NOTE: All bulk fibrous products used in temperate to hot climates in West and North facing walls (southern hemisphere) may cause a problem due to direct contact with the sarking foil and indirectly touching the external cladding and therefore the hot north and west facing walls, causing a conductive heat path from hot external wall cladding through to internal wall lining (plasterboard). This is what we refer to as Hot Wall Syndrome.
Autex Polyester Quietsuf batts (acoustic batts) can be used on external walls if additional noise control is desired.
Foilboard 10mm, 15mm (most suitable in the range) 20mm, 25mm available. It is best if the foilboard is directly fixed to the timber stud framework using Foilboard fasterners and then a counter timber batten to fix the cladding to. This creates a double reflective airspace and an increased R value. This system will not allow conducted summer heat gain through the external wall.
Polystyrene Rendered wall applications
Kingspan (Closed Cell Foam)