All Stellaria products FAQs.
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Stellaria NZ Ltd is the NZ distributor for all Wienerberger, Internorm, BOEN and MST Marbles products.
Wienerberger, Europe is one of Europe’s largest multinationals producing clay construction blocks, clay roofing tiles, clay facing bricks, clay facing tiles and clay pavers & piping systems. Founded in 1819, Wienerberger was publicly listed in 1901. Wienerberger now exports worldwide with 202 plants in 30 countries and is the global market leader for clay facing bricks, roof tiles and pavers. Wienerberger stands for high-quality natural clay products, which are marketed under the brands KORAMIC, POROTHERM, TERCA, PENTER and ARGETON. Wienerberger produces roof, wall, façade and paving from pure natural clay. Brick is one of the oldest building materials in history and therefore sets a perfect example for the modern concept of sustainable products. Wienerberger is exemplary for its environmental and business ethics, diverse designs and creations, energy-efficient construction and durable quality, holding their value for a very long time. Building with Wienerberger therefore, represents an economically and ecologically sound investment for the future.
Allow 100mm for the brick, and 50 mm for the cavity.
Tumbled bricks are ‘tumbled’ in a large drum containing stone chips and sand to create an old and aged look.
A bagged finish is a very thin, watery plaster applied over the bricks to give an aged and stressed look without losing the definition of the individual bricks.
Yes – Salting (commonly called efflorescence) occurs naturally on all natural clay (not concrete) bricks, but it comes mostly out of the mortar, and not the bricks themselves.
Generally, salting will naturally stop with exposure to weather and rain after around 6 – 12 months on its own, depending on brick thickness and size, and exposure to the weather. You can wash your brick facade if you wish, with a soft brush and clean water, but know that your brick will stop salting after around 6 – 12 months naturally, so there’s no need to worry about it. We do not recommend water blasting your brickwork as this may cause damage to the surface of the brick.
Any brick can – in areas with excessive moisture, inadequate ventilation, or a significant lack of sunlight or air movement. Bricks are a porous, natural product. Don’t worry – mould has absolutely no effect on the structural integrity/strength of the brick itself as they are a natural clay brick that is 100% organic and inert.
With the standard 100 series Terca brick, any positive or negative detailing can be created. This is the limitation with commercial, mass-produced 70 series bricks. If 70 series bricks are laid out of alignment, then they may no longer comply with the NZ building code.
No. They’re exactly the same price, because of the need to maintain quality and cut them from the ‘parent’ brick.
Yes. Any bricks can be blended, just ensure that the bricks are all the same length, height and depth.
Refer to the 2021 catalogue of blended brick series under brochures on the .
Rustic bricks take on a whole, recycled, traditional look. They appear uneven in texture, form and colour, to provide an aged, classic look, which is usually characterised in 100+ year-old buildings.
No maintenance is needed – that is the essence of brick cladding.
Mechanical bricks are machine wire-cut bricks with very straight, crisp, sharp edges. They tend to be used in designs that are more ‘industrialised’, modernistic projects, with clean and fine lines. On the other hand, handmade bricks have a more soft, natural, aged appearance, where a softer and more natural look is wanted.
You have many options with numerous, elastomeric cement-based adhesives that can be used to fix brick slips to cement-based substrates. (Sika, Ardex, Mape, etc.). We recommend only cement-based substrates, not timber-based substrates. If you’d like more information, contact us directly.
We always recommend Mason’s brick ties. The higher the level of the brick facade, the more brick ties required per m2.
There is a mortar colour to match every brick, and the colour of mortar joint will depend on the design of the brick facade. So bagged brick will give you the aged look; raked joints will give you individual definition of every brick; flush mortar joints will give you a more monolithic soft look to the wall.
Every Terca brick we offer has a DoP. (Declaration Of Performance). They’re a kiln-fired clay product and as a result, they have a durability well in excess of any other cladding system. However, bear in mind that they will only be as good as the substrate they are fixed to.
Eco bricks are a more cost-effective, slim-line brick meeting the market for minimum-thickness veneer bricks. However, they lack the thickness for any significant detailing.
This brick has the mortar laid to the centre of the brick which creates a ‘dry-stone’ effect to the wall cladding. Looks like stone but is clay brick.
Any brick veneer only offers the advantage of solar gain if there is no insulation between the brick and the built environment. In other words, no room will benefit from solar gain from brick veneer with timber frame where there is a layer of insulation between the brick and the room.
Yes. They’re a kiln-fired product with an A-rating in fire resistance, which is the highest possible rating.
Soft mud bricks (or stock bricks) are produced using a similar methodology to handmade bricks but using a machine.
These are 24-hour kilns that fire the clay bricks to 1200 degrees Celsius.
We usually recommend a maximum of up to 10% as the bricks are of high quality and breakages will generally never occur during transit from Belgium.
This is extremely rare, if ever; they never have to date. But if this is the case, our marine cargo insurance will cover any breakages.
Mostly Belgium, but occasionally France and the Netherlands.
Every brick comes with a technical producer’s statement which cross-references all of the NZ/Australian building code with European building code requirements. European building code requirements far exceed NZ and Australian building code standards.
It depends on the colour of the brick you’ve chosen and the final look you’re after. If you want to highlight the individual bricks, use a contrasting colour. If you want to create a quieter, more monolithic effect, choose a matching colour to the brick. Again, contact us directly for more advice, we’d love to help you out.
Yes. Every single one of our bricks has its own Declaration of Performance (DoP).
Standard clay brick installation as per NZBC & NZS.
We recommend EzyMix bagged mortar colour options, which is a specific brick veneer structural mortar, with around 9 different colours. You can look at mortar colours . Alternatively, standard masonry mortar is readily available, which is just a grey cement colour. If you’re unsure, contact us directly and we’ll answer your questions.
It depends on the colour of the brick you’ve chosen and the final look you’re after. If you want to highlight the individual bricks, use a contrasting colour. If you want to create a quieter, more monolithic effect, choose a matching colour to the brick. Again, contact us directly for more advice – we’d love to help you out.
Random bond is a pattern where the vertical joints have no regularity between the courses.
This means the Terca bricks will be deliberately sized and divided into 3rds and 1/2s to create a random look in each course. This creates a cobbled, authentically traditional appearance.
To create a unique and standout look for your brick facade.
Porotherm is a natural fired, solid clay construction block. It is available in a range of sizes, complete with accessory blocks (Lintels and Portals) design-engineered in accordance with the NZ building code requirements for each project and seismic region. Solid clay construction now forms up to 80% of the building material choice throughout Europe. Clay and lime have been used for hundreds of years and is now used extensively throughout the world.
Clay construction is design-engineered to be twice as strong as conventional construction methods. POROTHERM, in it’s current form, has been used extensively throughout Europe for the over 50 years and is now used worldwide in many high seismic zones such as Russia, China and Europe. Rigorous shake table testing documentation is available to show the extent of tests carried out by Wienerberger Engineers, meeting the highest Euro standards. This construction method is extremely earthquake resistant.
The acoustic rating for R25 is Rw + C 42. LR42Th+ is Rw + C 44.
Due to the thermal matrix design of the clay block most commonly used in NZ, R25Th+ at 250mm wide and kiln fired at temperatures of 1200c, water penetration is minimal. A breathable plaster system being waterproof and organic with mineral paint exterior finish is applied to meet E2 requirement.
Standard masonry fixings or Hilti Screws available in NZ.
Chases are cut in the walls at a depth of 30mm. This is easily and quickly achieved by a builder, blocklayer, plumber or electrician using a double saw chase cutter with a vacuum.
A standard 250 Th+ Porotherm block requires 8 blocks per m2. By comparison, standard concrete blocks require 12.5 blocks per m2.
Porotherm is 4 times faster to lay than traditional concrete building methods being a confined masonry system. The steel & concrete is only required, depending on the engineering in the lintels over the openings and the portals installed up to 5m increments along the wall. This has a significant impact on the end cost to build. Labour cost is the largest component of costs to any construction company or builder. Porotherm significantly reduces this.
The design life of Porotherm is 150 years. The life expectancy of the clay block is many generations.
Porotherm Clay blocks have a guarantee of 100 years. Installers are certified by Stellaria NZ.
Yes, absolutely. Totally natural clay construction. The Wienerberger sustainability story is at the heart of all their operations. To offset the carbon footprint required to transport from Europe to NZ, Stellaria offers 5 native or specimen trees (of your choice) to everyone building in Porotherm. We believe this gives something back to the environment the only element Stellaria NZ takes from the environment – the cost to ship it here!
None. Porotherm 250 Th+ has a F.R.R of 3 hours minimum.
Sentinel-Haus Institut, the European centre for healthy building skills.
EMISSIONS DANS L’AIR INTERIEUR – Volatile Substances in Indoor Air.
AVEC LA TERRE CUITE means with clay, No Development of Mould.
ENVIRONNEMENTALE ET SANITAIRE is a Health Declaration.
NATUREPLUS – Respect for Saving Non-Renewable Resources.
QUALITEL – Acoustics & Thermal certificate Lower Energy & Maintenance.
AFNOR NF – characteristics certified by the French NF norm for clay blocks.
EXCELL ZONE VERTE – Green Certificate.
A lime-based plaster system is highly recommended to retain breathability of the block. Any cladding system can be used on Porotherm.