September 2018

At Locker Group we make no secret of our love for perforated metal. We have over 60 years experience in manufacturing this bold and versatile product, and know how much it can add to both the interior and exterior of architectural projects.

However, you don't have to just take our word for it. This article gives 4 recent examples of perforated metal in architectural action from across the globe. Prepare to be amazed:

1. The Miami Museum Garage

Any building constructed in Miami's Design District will have stiff competition when it comes to standing out from the crowd – this area is known for innovative design, art and architecture.

We'll let you judge for yourself, but we'd say the Miami Museum Garage does a pretty good job. The facade is inspired by ant colonies, with the structure representing a similar hive of activity. Public areas such as a playground, a garden and an art space are selectively shown, with the rest of the building disappearing behind an epic perforated metal screen.

This is a perfect example of why perforated metal is excellent for use in facades. Not only is it visually striking, this building makes use the material's natural capacity for sun and wind shelter while also permitting great air and light filtration.

2. Yokohama nursery

There are many aspects of the Yokohama nursery that make it a great piece of architecture. From the warm interior feeling created by the plywood boards to the windows designed to resemble traditional dwellings in the area, every aspect is well thought through and well executed.

However, the aspect of this building that really stands out to us is the perforated metal facade. Not only does it stand out from the white structures on either side of the nursery, the perforation pattern has been cleverly arranged to resemble the constellations of a galaxy. Now these kids get to literally play among the stars!

3. Salesforce Transit Center 

Opened to the public on the 11th of August 2018, the Salesforce Transit Center is a truly iconic addition to the city of San Francisco. The building, which was 17 years in the making and will serve as a central transport hub for the city, is said to be inspired by nature as well as art and math. 

The design features a jaw-dropping 3,992 perforated white aluminium panels, decorated with an intricate geometrical pattern designed by mathematician and physicist Sir Roger Penrose.

For those who want to take things a step further, Locker Group offers a Pic Perf range of facades where images can be precisely perforated into the metal sheet, creating a truly unique and eye-catching result.This structure really shows off the artistic capabilities of perforated metal. One of the features of this product that makes it so engaging for architects is the fact that there is an almost limitless variety of patterns and shapes that can be punched in.

4. The Vancouver 'Tree House'

Here's one for the future. 

The slopes of West Vancouver will soon be graced with the presence of a 12 story condo building, which at this point is being called the 'Tree House'. 

The facade will feature a range of materials including dark painted metal, exposed concrete and, you guessed it, perforated metal. Here, perforated metal will be used in the soffits of individual units which will cantilever from the main structure.

The material was chosen for this project for reasons similar to the Miami Museum Garage – namely its ability to provide visual contrast and shade. The 'Tree House' is designed to blend into its surroundings, and the capacity that perforated metal has for establishing natural feeling light flow will be of great use in fulfilling this aim.  

We hope this article goes someway to showing you the amazing potential that perforated metal has for use in architecture. Each of these projects use the material in different ways, and architects need to be able to count on suppliers to deliver products on schedule, and to their exact specifications. Locker Group prides itself on working closely with our clients to ensure that high quality and reliable deliverables. 

With so many ways to treat and finish metal products, it can be hard to choose which method is best for your project. Since the 1970s, powder coating has been a favourite option among architects due to its versatility and durability, as well as its eco-friendly credentials. But how does this technique work, and what makes it so popular?

Here's the Locker Group guide to powder coating in architecture.

Architects need to consider the stages of the powder coating process.

The process of powder coating

Powder coating is the addition of a protective plastic layer to a metal substrate using a spray gun. It may sound like child's play, however there's a little more to the process than meets the eye:

• Do I need to prepare the metal? Before any spraying takes place it's crucial that the metal is decontaminated and cleaned. The presence of unwanted substances on the base product may mean the powder doesn't stick well, causing bumps and other unwanted features. Common contaminants include grease, corrosion patches, oil and mill scale. Later on we'll discuss which pre-treatments best suit different metal types.   
• What's in the coating? The spray emitted from the gun comprises ingredients including polymer resins, levelling agents and pigments, which have been melt mixed and ground into a powder. By changing the colour of the polymer, you are able to get a wide variety of different colour coats.
• How does it stick to the substrate? The spray gun itself supplies an electrostatic charge to the powder particles (a process called electrostatic spray deposition), meaning they're attracted to the earthed metal.
• Why is this process so effective? The adhesive properties of the coating are increased further when the parts go through a curing oven. The heat reacts with the chemicals in the coat to create dense cross-links between the molecules that are very difficult to breakdown. 

The benefits of powder coating for architects

The process described above gives powder coats some unique characteristics that make it ideal for use in architectural projects. Here are some of the most important:

Choice – You can powder coat your chosen features in just about any colour, meaning powder coating provides aesthetic function in addition to the practical benefits we will mention shortly. However, don't stop at colour – from matte to ultra glossy you have an almost limitless selection of textures too.

Durability – Powder coats are long lasting. Unlike many of the paint based finishing techniques with which it's often associated, powder coating has a high tolerance for a variety of environmental conditions, as well chemicals and abrasion.

Environmental compliance – 2018 has seen awareness of human impact on the environment reach new levels, and it's important that architects and industrial practitioners minimise their negative effect on the planet. There are a number of features of the powder coating process that make it more ecologically sound than many alternative techniques:

• It eliminates, or greatly reduces, the emissions of volatile organic compounds (VOCs), which are traditionally found in paints.
• Powder coating also minimises or removes the release of hazardous air pollutants (HAPs) associated with conventional liquid coatings.
• If more powder is sprayed than necessary, the excess can be retrieved for future use.
• Powder coats usually don't contain heavy metals that can be dangerous for people as well as the environment.

Powder coating is more environmentally friendly than most wet paint techniques.

Which metals suit powder coating?

The good news if you like what you're hearing about powder coating so far, is that it's a technique applicable to a wide range of products. For architects this means that it can be used extensively on both the inside and outside of builds. 

Here we'll have a look at three specific metals which are the primary materials for many of our favourite products. They all make excellent candidates for powder coating, but require unique treatment prior to spraying.

1. Aluminium – The lightweight yet strong nature of aluminium means that it's a firm favourite in building design. However, the oxide coating that gives aluminium its rust resistant reputation must be removed prior to powder coating to allow the polymer to bond with the metal itself, rather than this protective outer layer. This can be achieved through surface blasting or submerging the metal in a phosphate solution.
2. Galvanised steel – As galvanised steel has already been finished (through the process of galvanisation), it may seem like an odd choice to include here. However, as powder coating adds another layer of protection, this substrate is actually one of the most common to undergo the process. In addition, the fact that galvanised steel has the capacity to form a layer of zinc oxide or zinc carbonate, similar to the oxide layer on aluminium, means that similar techniques must be employed to remove this before spraying can commence.
3. Stainless steel – For stainless steel the focus is on profiling the surface of the metal to make it easier for the powder to stick. This could involve blasting with a sharp substance such as aluminium oxide or, at a more advanced level, an acid etch. 

A few drawbacks

While powder coating has a lot going for it, it wouldn't be fair to paint it in a perfect light, if you'll excuse the pun. Here are two drawbacks you should consider:

• Achieving a thin layer is difficult – This is due to a relative lack of control over the rate and amount of powder applied to the target. If you're looking to apply 6 millimetres or less, this isn't the technique for you.
• It's hard to remove – We told you it's durable. However, the flip side of this advantage is that removing powder coats will take some time if mistakes are made.

Powder coating is a useful tool in an architect's arsenal, but only when implemented correctly for your unique project. At Locker Group we work directly with our architectural clients to deliver products tailored to your requirements, engaging with you every step of the way.

So you've decided to incorporate woven wire into your next architectural project. Firstly, congratulations – you've chosen a versatile and aesthetically interesting product that can be used to add flair to a wide range of builds. 

However, now you're faced with the happy problem of choice. Due to its ability to perform both visual and practical roles in the design of a building, and the fact that it can be used internally and externally, there's a fair bit of thought required when selecting woven wire for use in architecture.

Here are a few factors to bear in mind:

How will it function?

With a variety of materials and profiles to choose from, you need to consider the function of the woven wire you're planning to install.

Woven wire has a number of common purposes, including:

• Sun shading.
• Providing a shield from wind and rain. 
• Creating a partition. 
• Allowing the flow of air and light through a space.

However, a wire mesh feature intended to give a feeling of privacy is clearly going to require a different profile to one where the desired outcome is allowing more light into an area.

For example, in the redevelopment of the PwC premises in Sydney, Design Director Gavin Harris wanted a woven wire product for the ceiling that allowed transparency and reflectivity without losing light, aesthetics or sound in the space. Ultimately Locker Group's Planar 441 provided exactly the right balance, and was incorporated into this unique and interesting design.

Will it be used internally or externally?

Clearly there are different requirements for any metal-based architectural feature depending on whether it's used internally or externally. Wire mesh used to provide a feeling of privacy in a restaurant will be under a lot less stress from the elements than the same feature used to create a 3D effect on the outside of a building.

In addition to choosing the woven wire mesh that's best suited to the environmental conditions of your project, it's also important to think about finishing techniques. As well as protecting the metal substrate from the elements, finishing techniques can enhance its the visual proprieties – contributing to how it will impact your design.

How much does it weigh?

The relative weights of the elements you include in your building design are of great importance when establishing safety and costs. We'll return to costs in a bit more detail later, but let's have a look at the weights of woven wire mesh, and what this means for your design.

Of all the metal materials you're likely to use in your project, woven wire products will probably be the lightest. They range from 0.178 kilograms per square metre (kg/m²), for grade-316 stainless steel, to 8.1 kg/m² for galvanised steel. 

Whilst there are obvious benefits of using lightweight elements such as wire mesh, there are still important safety considerations – especially for architectural applications such as building facades. The installation of any panel facade, whether wire mesh or perforated metal, should be preceded by a thorough examination of the fixing system, and what the implied load will be for the support structure.  For external uses, it's also important to factor in wind loads, especially on corners. 

AS/NZS 1170 is the most important standard regulating load requirements for buildings, so ensure that your mesh manufacturer is able to provide full certificates for the products they supply to you.

As well as the implications for the building itself, you should consider how weight will impact on the ease of installation. Returning to our example from the PwC design in Sydney, a supporting spring line was required to ensure a fast and safe implementation of the woven wire on the ceiling. Making these considerations in advance can save you time and money when it comes to bringing your design to life.

What will it cost?

After safety, costs and deadlines are the biggest considerations. Builds have tight budgets and timeframes, so you need to ensure that the materials you choose aren't going to break the bank or cause you to fall behind.

This, again, is where the lightweight nature of wire mesh really comes into its own. Woven wire mesh is typically easy to install, reducing labour costs and helping you stick to deadlines.

For example, when Locker Group supplied stainless steel woven wire for use in Vogel House, a high profile building in the parliamentary district of Wellington, New Zealand, the installation process was completed in a matter of days. The mesh was delivered in three rolls and attached at the top and bottom of the staircase it was screening, with Locker Group providing technical assistance to ensure a fast but safe installation. 

As such a versatile and easy material to work with, it's no wonder that woven wire plays a role in so many architectural designs around the world. Locker Group works closely with its clients to create tailored products that fit your requirements, and your budget.