The material choice (i.e. timber, PVCu, Aluminium etc) is down to personal preference, but it is important that the whole window or door design has proven performance characteristics.
PVCu windows and doors often have a lower initial cost and can have low maintenance requirements, but there is little scope for repair. Opening window casements and door leaves are more likely to flex, and will expand and contract more as the temperature changes.
Timber may have a higher initial cost, but a properly made timber window or door is likely to have a longer life span. Modern timber windows and doors that are manufactured and finished well are likely to be very durable with minimal maintenance. They are also easier to repair if required.
Aluminium often has a higher initial cost, but is normally stronger than PVCu, so is better for larger windows and doors (e.g. bi-folding doors), and can be used for structural applications. Aluminium windows and doors often require less maintenance, but there is less scope for repair if something goes wrong.
