INSULATION
Except for our basic model option (single-sided), all of our models can be insulated. The double-sided model options (standard, premium, and superior) all have a cavity that can be stuffed with any type of insulation material. Recent studies have indicated that roof insulation (*) uses either glass wool. rockwool or polystyrene foam is not the most effective. A system making use of an air barrier seems far more effective, a system that is based on a minimum required air gap between the roof decking and roof ceiling created by longitudinal and lateral crossing furring strips. A special in-house developed roof construction is applied to guarantee the proper insulation index (the R-value) for this system. A correct thickness of the furring strip layer is essential. Too thick or too thin an air gap and insulation will not work. The air gap thickness needs to be exact to comply with the insulation index parameter which is normally provided in the building codes and may vary from country to country. Prefabworld Bali International has developed a calculation method to define the proper air layer thickness which has been approved worldwide.
(*) Mandatory for all Hawaiian islands
Rockwool
Glasswool
Polystyrene
The standard roof assembly for our houses(from top to bottom) is as follows:
- Roof decking material (roof tiles, corrugated sheathing, thatch, or wooden shingles)
- Battens
- Rainproofing (hessian asphalt felt, 2 layers of aluminum foil or any other type)
- Plywood with a certain thickness
- Upper layer furring strips layer (proper thickness is not disclosed here) (*)
- Second layer furring strips layer (proper thickness not to be disclosed here) (*)
- A layer of a radiant aluminum foil barrier (*)
- Plywood with a certain thickness (*)
- Ceiling material
- Purlins
- Rafters
- Truss system
(*) The furring strips system will only be installed upon approval of the client. The thickness of the furring strips is crucial and needs to be properly calculated to obtain the optimum air gap and is based on the thermal index (R-value) related to the outside temperature and inside temperature.