Updated: May 3, 2020
Cladding is one of the most important decisions you'll make when it comes to building, buying or renovating your home.
New technologies and materials are changing the face of how our homes look and there are a huge number of alternatives out there.
There are many options available now for the external walls and the envelope of the building is of very high importance. So what considerations should you take into account?
What is the Insulation (R-value) when you choose a particular system? Remember, the higher the R-value, the lower your power consumption and generally, the improved health of your family.
Is the structural integrity and bracing values suitable for your site? Ensure you check concrete strength after curing.
Should water penetrate into the external walls, what materials can break down internally and how does this effect the structural integrity of your home?
How does your chosen system weigh up in terms of value? Remember, it is not only the cheapest option you need to look at but consider what ongoing savings you will make through less maintenance. Also consider the environmental impact – from manufacture through to left-over waste.
What claddings can I use over my system? Make sure you can choose something that will provide protection from the elements.
Don’t be afraid to ask for the supporting information to give you the comfort level that you have made the right choice.
Some wall cladding options are:
Weatherboards are shaped planks fixed horizontally and lapped over each other. Rainwater drains down the outside and can only get inside if it is forced upwards between the boards. There are new installation techniques that can greatly speed up application, keeping costs down. As well as timber, weatherboards can be made from materials such as fibre-cement, metal and vinyl (PVC).
Fibre cement exterior wall coverings come in the form of panels and weatherboards. They may be used as the exterior wall covering, or as substrate for monolithic claddings.
Plywood panels may be used as cladding. Gaps are covered with battens or flashings. You can also get plywood weatherboards.
Masonry veneer is a system where a timber-framed home is clad with bricks, stone, or thin concrete blocks. The masonry is connected to the timber framing through flexible wall ties.
Concrete blocks or poured concrete may act as both the structure and the cladding.
Plaster as an exterior cladding provides a clean, and seamless appearance providing an attractive aesthetic to most construction types. It allows for virtually unlimited colour selection, and textural style. Plaster Claddings are applied over a 'rainscreen, drainage' cavity, as with the majority of external claddings today, allowing incidental moisture to drain away, in a similar way that brick veneer, and weatherboard cladding does. Solid Plastering and Proprietry Plaster Claddings are registered, specialist LBP (Licensed Building Practitioner) trades, as such you should investigate reputable system suppliers and qualified registered plasterers that have industry recognised qualifications for the installation, and finishing of the exterior.
There are many different substrates to which plaster can applied the most common include; Brick veneer, solid filled concrete block (new or existing), EIFS (polystyrene), AAC (lightweight masonry panel), fibre cement sheet.All exterior plastering, as with timber weatherboard requires maintenance in the form of cleaning and re-painting.
Metal – Aluminium cladding is extremely durable, lightweight, leak proof GRC or GFRC - A composite material comprising a mixture of hydraulic cement, silica sand, alkali resistant (AR) glass fibres and water.
Major considerations are aesthetics, durability
Waterproofing is a huge concern, but building procedures used in the past for certain products that created problems have largely been addressed and homes being built now use specific techniques to avoid problems.
Options for external cladding will play a major role in how your home looks, so investigate widely for cladding you like that fits with the style of home you’re building.
You can mix different cladding types, too.
Wall cladding must protect the interior from water penetration under all conditions, including rain driven by high winds. It should also stop draughts.
Drained and vented wall cavities - Some cladding systems work on the assumption that some water will inevitably penetrate the outer skin of the building. A cavity between the outer wall covering and the interior lining allows water to drain away through drain holes and air to circulate. With most types of cladding, in all but low-risk situations, a dry cavity is now required under the Building Code.
Wall underlays or building paper - Building paper and synthetic wraps prevent any moisture which does enter the wall cavity, or has got in behind the cladding, from getting into the framing and interior lining.
Flashings - Flashings are strips of metal or other material that cover joints and gaps where water can get in. They are used around window frames, external doorways, and on top of exposed walls, to help stop water getting in, and help to drain it out.