Windows with the same dimensions are not necessarily equivalent
Dimensions are only one part of a window specification. Profile system, opening type, glazing, thermal and acoustic targets, finish, shutters and accessories can all change the final configuration.
- Profile material and system
- Dimensions and sash layout
- Opening type
- Full glazing make-up
- Thermal and acoustic performance
- Air permeability, watertightness and wind resistance
- Finish, shutters, accessories and security requirements
Window system and glazing
The frame system influences glazing capacity, geometry, gaskets and the range of achievable performance. Aluminium systems with thermal breaks and PVC systems with different chambers, reinforcements and gaskets should be compared as complete systems rather than by material name alone.
Glazing can combine double or triple units, low-emissivity coatings, solar control, laminated or acoustic glass, different cavities and warm-edge spacers. The right make-up depends on climate, orientation, noise, dimensions and room use.
Opening type and whole-window performance
Fixed, casement, tilt-and-turn and sliding windows behave differently. Opening type affects sealing, ventilation, clear opening, available dimensions and day-to-day use. Two quotations are more meaningful when the opening arrangement is equivalent.
Useful technical references include Uw for the whole-window thermal transmittance, Rw for acoustic performance, plus classifications for air permeability, watertightness and resistance to wind load.
Dimensions, shutters and accessories
Larger openings can require different profiles, hardware and glazing weights. Large sliding doors are therefore not directly comparable with small conventional windows.
Shutters, boxes, insect screens, handles, security hardware, automation and accessibility options are also part of the specification and should be clearly identified.
How to compare two window quotations
Before deciding, check that both proposals describe equivalent solutions.
- Same dimensions and sash layout?
- Same opening type?
- System clearly identified?
- Full glazing make-up specified?
- Comparable whole-window performance?
- Same shutters and accessories?
- Equivalent finish and security requirements?
This turns the comparison into an assessment of the solution, not just one number.
Choose the required performance first
Start by defining what you need to improve: thermal insulation, noise reduction, solar control, security, weather tightness, large dimensions, design or a combination of these. From there, suitable CORTIZO systems and configurations can be compared on a like-for-like basis.