A window or door frame forms the surround supporting glazing and opening components. The complete assembly includes more than frame material. Panel divisions, moving parts and the connection to the building influence its final arrangement.
How this term relates to your project
For an extension, frame dimensions must match the settled opening and intended finished floor height. Establish whether quoted sizes describe external dimensions, internal dimensions or clear access. Specify material, colour, glazing, controls and perimeter finishes. The wall connection requires attention to water, air and insulation; frame product data does not automatically describe that building junction.
Compare quotations by the complete unit and installation scope. Include maintenance and access to moving components. Retain the final product specification with the drawings so later replacement of a part can be based on the actual installed configuration rather than an early proposal or generic product name.