Does radiant barrier attic application require ventilation, and if so, what type (ridge, off-ridge, soffit, etc.)?

No, they work with or without ventilation but will perform better in ventilated attics. According to the building code, all attics in Florida must be vented.

Extended Version: Studies have shown that with or without a radiant barrier, a ventilated attic is best and the same holds true for a radiant barrier. A house will perform better with a radiant barrier and a ventilated attic than a house with a radiant barrier and a non-ventilated attic. Houses must be designed to meet the building code, which has ventilation requirements with or without a radiant barrier. In both cases, it is the ventilation rate that is important, not the method or type of ventilation.

Product Reference: 

Silver Shield
FSK Shield
Radiant Shield

Market Reference: 

Single Family

Professionals Reference: 

Builder
Insulation Contractor
Remodeler
Engineer
Homeowner
Architect

Product Applications Reference: 

Attics
Attics
Attics
Attics & Ceilings

Building Type Reference: 

Masonry
Metal
Wood Framed

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