Aluminium and glass facades and shopfronts

What decides the price of a shopfront or facade

A facade is always made to fit the building, so two openings of the same size can cost quite differently. What weighs most:

• The size of each pane. Large single panes look best, but they are thicker, heavier and need special transport and lifting. Splitting the shopfront into two or three panes reduces the cost considerably.
• The type of glass. Single laminated, double, solar control or acoustic.
• The profile system. A shopfront in a standard window series is cheaper than a mullion-and-transom facade designed for great heights.
• The doors. A hinged door with a closer is simple. Swing doors, automatic sliding doors or doors with access control add to the price.
• The existing structure. If the lintel, pillars and floor are straight and sound, fitting is straightforward. Out-of-square openings or deteriorated concrete need preparation.
• Access and hours. Working at height, over the public road or out of hours has its own costs.
• The finishing. Flashings, thresholds, pillar casings and composite panel around the shopfront.

For a first figure, the measurements, the photos and how many doors you want and where are enough.

Which glass to choose: safety, sun and weight

In a shopfront, the glass is almost everything. Three questions help you choose:

What happens if it breaks? For shopfronts, glass manufacturers recommend laminated glass: two sheets bonded to an interlayer that holds the fragments and keeps the opening closed even when the glass is broken. Toughened glass is much more resistant to impact, but when it breaks it shatters into small pieces and leaves the shop open. For doors and walkways, laminated glass made from toughened sheets can be used, which combines both.

How much sun does it get? A shopfront facing south or west heats the shop and fades whatever is on display. Solar control glass reduces the heat coming in, and laminated glass itself filters out almost all ultraviolet radiation, which protects the goods in the window.

How much does it weigh? Each square metre of glass weighs 2.5 kg per millimetre of thickness. A shopfront pane three metres by two and a half, in 10 mm laminated glass, comes to nearly 190 kg. This determines how many people and what equipment are needed for fitting and replacement.

A word of warning: toughened glass cannot be cut or drilled after it is made. Holes for handles and cut-outs have to be right in the order.

How the job goes in a shop that stays open

Replacing a shopfront does not have to mean closing the business for days. The work is organised so that the opening is left open for as little time as possible:

• 1. Measuring and specification. Accurate measurements, division of panes, door positions, colour and type of glass. It is also when we work out how the glass gets in and where the van can stop.
• 2. Manufacturing. The frames and glass are made to measure. Nothing is taken down in the shop until all the material is ready.
• 3. Preparation. The day before or on the day itself, the area behind the shopfront is cleared and the floor and anything nearby are protected.
• 4. Removal and fitting. The old shopfront comes out, the new frame goes in, then the glass and doors. With a standard shopfront, the aim is for the shop to be closed and secure at the end of the same day.
• 5. Finishing and adjustment. External sealing, internal finishes, adjusting the doors and closers.

Two things worth sorting out in advance: occupying the pavement or road, which in many municipalities needs permission from the town hall (câmara municipal), and the alarm and sensors connected to the old shopfront, which should be disconnected and reinstalled by whoever fitted them.