Installing Foil building wrap
Foil building wrap is insulating material that is fixed to the timber frame before the timber or brick cladding is added. It can be fitted to steel framed houses but you must use wide head metal screws and not staples.
The two main types are foil wrap for walls and foil wrap for roofs and under floor. For walls that will be clad with timber or cement sheeting, the foil must be breathable to control moisture build up. This type will have very small holes punched through the foil. If the foil is to be install under roofs, floors, and brick cladding the foil is not breathable and helps to repel moisture.
Foil Wraps are reflective and help to provide an insulation barrier to the radiant heat, vapour, and a second skin that will keep out driving rain, dust, and wind.
Installation of wall foil wrap
Step One: Select your type:
Select the best types for your situation and buy 10% more than you need. This will cover cutting and joining. Also buy foil joining tape to seal the vertical joins.
Step Two: For Walls:
Start from the bottom of the walls and overlap the horizontal joins so if water was to run down the foil wrap it would not run into the house. You can use a (large) staple gun or knock in clips with a hammer. However a staple gun is quicker. You can hire a large staple hammer which similar to a hammer and is used like a hammer but knocks a staple in as you hit (very fast).
Step three: Tape the joins:
With the foil tape, tape all your joins that are not over lapped by 100mm and any damage to the foil wrap.
Installation of foil wrap for roofs
This is the same process as the above wall installation. However you start at the bottom of the roof 
or gutter edge and work up towards the peak of the roof. Overlap by a 200mm and make sure the foil wrap is fairly tight this helps to minimise wind blowing in dust and rain.
Types of foil insulation
- Light foil: generally used for walls only
- Medium: Generally for walls and roofs in non extreme zones
- Heavy duty: For hot and cold zones that need extra thermal protection
- Fall arrest and hail Resistant: Theses types are thicker and provide extra protection for roofs.
