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Energy efficiency: what the ratings mean
Uw values, glazing options and why the right window specification saves on cooling and heating in southern Portugal.
What Uw actually means
Uw is the thermal transmittance of the whole window — frame and glass together. Lower is better. A strong glass unit in a weak frame still loses performance at the edges.
Algarve priorities
Here cooling load often matters as much as winter heat loss. Pair a sensible Uw with solar control so rooms stay usable in August without overworking air conditioning.
Need a specification for your home?
Free measurement and a quote that accounts for coast, orientation and how you use the house.