Could a triple glazed unit be worse than a double glazed unit?

Yes, if a triple glazed unit is squeezed into the same 28mm space as a double glazed unit, it may actually perform worse in terms of energy efficiency. This is because: 

• Cavity widths are reduced, lowering insulation performance. 

• Incorrect Low-E coatings may be used, reducing thermal benefits. 

For optimal performance, triple glazed units should have wider cavities (e.g., 32mm-36mm thickness). 

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