SEC 01 / Why it matters

Why roof ventilation matters

A roof cavity is where the house’s heat and the house’s moisture both end up. What happens next depends on airflow.

On a summer day, the space under the sheeting can run far hotter than the rooms below. It then feeds heat down through the ceiling all evening. In contrast, on a winter night the sheeting becomes the coldest surface in the building. So the warm, moist indoor air that leaks upward condenses on it. As a result, the National Construction Code has moved steadily toward managing exactly this. Specifically, its condensation management provisions push designs to give moisture a way out. A cavity that can breathe sheds both problems; a sealed, still one stores them.

SEC 02 / The air gap

Creating an air gap with steel battens

This is the batten’s quiet second job. Fixed over the sarking or insulation blanket, a top hat batten’s crown holds the roof sheeting off everything below it. In other words, the standoff equals the height of the section. For example, that is 40mm for our roof profile, and 22mm where the ceiling profile is used. The result, then, is a continuous gap on the cold side of the sarking. First, it works as a drainage plane where condensate can run off. It is also a channel through which air can actually move. Indeed, it is a simple detail that much of good roof ventilation practice is built on.

SEC 03 / Energy efficiency

Benefits for energy efficiency

The gap earns its keep twice on energy. For instance, reflective foil facings only insulate when they face an airspace. So the batten cavity is what lets a foil sarking or blanket actually perform to its rating. Moving air in the gap also carries part of the heat load away before it reaches the ceiling insulation. As a result, that shows up as cooler rooms in an Adelaide summer, and less work for the air conditioning. Of course, neither effect replaces bulk insulation. Instead, both make the roof system around it work as designed.

SEC 04 / Moisture and mould

Preventing moisture and mould build up

Mould needs a damp surface and still air, and the batten gap attacks both. For example, condensation that forms under cold sheeting lands on the sarking. It drains, rather than pooling against timber or insulation. Meanwhile, the airflow through the cavity dries what remains before it lingers. So pair the gap with actual vent points, at the eaves, the ridge or both. As a result, air has a way in and out. The cavity then stays in the dry zone where mould does not start.

SEC 01 / Specifications

Product specification comparison

In fact, the clearest comparison is simply what each company would deliver to your site.

Interspan is a Sydney headquartered specialist engineering group, founded in 2006. Specifically, it designs and installs post tensioning systems for concrete structures, across slab, multi strand and stress bar systems. It also delivers structural strengthening and remediation work. For example, that covers carbon fibre strengthening, concrete repair and cathodic protection. Moreover, it operates across Australia and internationally, with a workforce in the hundreds. Then in 2026 it became part of the global DYWIDAG Group. Kspan, in contrast, is an Adelaide fabricator with a deliberately narrow catalogue. We roll steel top hat battens, in a 22mm ceiling profile and a 40mm roof profile. The steel is coated G550 high tensile, in standard or custom lengths.

SEC 02 / Quality control

Quality control and manufacturing

The two companies answer to different kinds of rigour, and both kinds are real. For example, post tensioning lives in the world of certified systems, engineered design and site verification. After all, failure on those structures is not an option. Indeed, the Sydney group’s standing on major projects speaks to how seriously that is done. Batten fabrication, however, lives in the world of repeatability. Specifically, that means steel to AS 1397 and sections made to comply with the relevant Australian Standards. It also means dimensional consistency, batten after batten. After all, a roof plane is only as true as the least consistent piece in it. Kspan runs one profile family through one Adelaide facility precisely so that consistency is the whole job.

SEC 03 / Local supply

Local Adelaide supply benefits

For a South Australian build that needs battens, geography does quiet, daily work. First, fabrication happens in Adelaide, and quotes go back within one business day on SA trade hours. Also, custom lengths and bulk runs come off the same line that rolls the standard stock. Finally, despatch reaches metro, the hills and regional SA without an interstate leg. So when the setout changes mid job, a top up run is a phone call and a short drive. It is not a freight booking.

SEC 04 / Choosing right

Choosing the right batten for your project

Your search may really have been about post tensioned slabs, transfer structures or strengthening an existing building. If so, Interspan and your structural engineer are the right conversation. In fact, none of our products replace that work. However, if it was about the steel that carries a roof or ceiling, the choice is a batten question. First, pick the profile by duty: 22mm for ceilings, 40mm for roofs. Then pick the base metal thickness by span and wind class, and the lengths by the setout. The full range is on the products page. Finally, spans get checked against the published data before anything is rolled.

SEC 01 / Manufacturer tables

Manufacturer recommendations for spacing

The sheeting maker publishes maximum support spacings for every profile and thickness. So that table is the starting point, always.

For example, take the classic corrugated profile in 0.42mm base metal thickness. Published design data lists a 700mm maximum for a single span, 900mm for end spans and 1200mm for internal spans. However, those figures hold under the publisher’s stated wind model, with supports of at least 1.0mm BMT. Meanwhile, step up to 0.48mm sheet and the allowable spans grow. The pattern to memorise is the end span rule. The first and last bays of every sheet run are held tighter than the middle.

SEC 02 / Wind rating

Factoring in wind rating in Adelaide regions

Every site carries a wind classification under AS 4055, from N1 up to N6 in non cyclonic areas. Also, published spacing tables are only valid within their stated wind assumptions. For instance, much of the Adelaide plain sits in the lower N classes. In contrast, exposed coastal edges, ridge lines in the hills and open rural sites climb higher. As a result, a higher class means tighter spacings, more fasteners per sheet, or both. The classification, of course, comes from the certifier, engineer or council paperwork. It is never guessed from the street.

SEC 03 / Roof pitch

How roof pitch affects spacing

Pitch mostly decides which profile you are allowed to use, and the profile then brings its own table. For example, traditional corrugated sheet needs about 5 degrees of fall to shed water reliably. Trapezoidal and concealed fix profiles, however, are rated to shallower pitches in their own literature. So the batten spacing Colorbond roof sheets need does not swing much with pitch directly. Instead, what pitch changes is the profile choice, and the profile changes the spans. Still, the one extra to watch on low pitches is water load and overlap detailing. The profile’s guide also covers both, alongside its spans.

SEC 04 / Sheet profiles

Sheet profile considerations

Rib height is stiffness. A 16mm corrugation, a taller trapezoidal rib and a deep concealed fix pan all span differently in the same thickness. As a result, every profile carries its own table. It is also why numbers never transfer between profiles. Besides, the sheet is only half the check: the battens underneath have their own span and screw pull out tables. Our steel roof battens publish capacity data for the 40mm top hat at the standard spans, in two thicknesses. So both layers of the roof can be checked against the same wind figure.

SEC 01 / The standards

Australian standards for batten spacing

In short, two documents do the talking: the lining standard and the lining maker’s own literature.

For example, on plasterboard ceilings AS/NZS 2589 covers how gypsum linings are applied and finished. Meanwhile, the board manufacturers publish the support centres their sheets are warranted at. So the spacing for ceiling battens on a job comes from those sources, not from habit. Also, it is always a maximum, measured centre to centre. However, a separate check governs how far each batten may bridge between joists or trusses. That is the batten’s own span table. In other words, it is a property of the section rather than the lining.

SEC 02 / Lining weight

How spacing changes with ceiling lining weight

After all, support centres exist to stop the lining sagging between rows. So the heavier and less stiff the lining, the closer the rows. For example, standard 10mm plasterboard sits at 450mm maximum. Stiffer 13mm board then stretches to 600mm. From there, the numbers only tighten further. For instance, fibre cement sheets, timber lining boards and acoustic panels all call for closer centres, from their own tables. The same goes for any ceiling asked to carry batts, as well as services bearing on the lining.

SEC 03 / Resi vs commercial

Residential vs commercial requirements

Residential ceilings are mostly a two number world: 450 or 600, set by the board. Commercial ceilings, however, arrive with more paperwork. For example, fire rated and acoustic systems are tested as complete assemblies. So the batten type, centres and fixings are part of the tested system, and cannot be swapped or stretched. Meanwhile, heavier multi layer linings pull the grid in. Also, services, seismic requirements or an engineer’s specification can override the board’s generic figure. In short, on commercial work the system documentation wins every time.

SEC 04 / Quick chart

A quick reference chart

For everyday work, this is the spacing for ceiling battens at a glance. In other words: maximums, centre to centre, always confirmed against the current literature for the exact product on site.

Our steel ceiling battens are rolled in Adelaide as a 22mm top hat, sized around exactly these grids. Also, lengths run at a standard 6100mm or as custom runs. So send the lining type and joist centres. Then we will confirm the spacing for ceiling battens on your job, plus the batten span to match. Nothing, in fact, gets fabricated before that check.

SEC 01 / Plan the layout

Planning the layout

Ten minutes with a tape and a pencil beats an afternoon of unpicking.

1. Measure the room and pick the direction.Battens run at right angles to the joists or trusses, so the frame above decides the direction before you do.
2. Start the first row near the wall.Set the first batten within about 50mm of the wall line so the sheet edge and cornice are both supported.
3. Divide the span by the maximum centres.Work out how many rows fit at or under the allowed spacing. Then even the rows out, so the last bay is not the wide one.
4. Plan the sheet joints.Plasterboard end joints must land on a batten, so sketch the sheet layout before marking the grid.
5. Order the lengths.Standard 6100mm steel ceiling battens cover most rooms in single runs; custom lengths remove joins on long ceilings.

SEC 02 / Spacing

Correct spacing for plasterboard

The lining sets the spacing. Standard 10mm plasterboard needs support at 450mm maximum centres; 13mm board allows up to 600mm. Both figures come from the plasterboard installation literature and AS/NZS 2589. Both are measured centre to centre. And both are maximums, rather than targets. Heavier linings close the grid up further, per their own manufacturer’s tables. Fibre cement, timber boards and acoustic systems all sit in that camp.

SEC 03 / Fixing to trusses

Fixing methods to trusses

At every crossing, fix through the batten flange into the truss or joist with two self drilling screws. Drive them perpendicular, and snug rather than crushed. Match the screw to the frame. Use fine thread metal screws into steel framing, and coarse thread timber screws into pine. Step up the screw specification when the frame member is thin. Under load, the fixing into a thin chord fails before the batten does. Where two battens meet along a run, land the join on a support, never in mid air.

SEC 04 / A level finish

Ensuring a level finish

Flat is built, not hoped for. Run a string line or laser across the grid, and pack any low crossings before sheeting. A millimetre of packer now is invisible. A millimetre of step between sheets never stops being visible. Rolled steel battens are dimensionally alike. So the packing you do is correcting the frame above, not the batten itself. That is a big part of why the how to install metal ceiling battens process is faster in steel.

Sight the grid from below, walk the perimeter, then sheet. That is the whole discipline of how to install metal ceiling battens. Respect the maximum centres, land joints on supports, and drive two screws per crossing. Then run a string line before the board goes up.

SEC 01 / The role

The fundamental role of battens in a roofing system

A roof is a skin stretched over a frame. Battens are the rows the skin is stitched to.

Ask what battens in roofing are there for and the answer is three jobs at once. They bridge across the trusses or rafters to create a continuous fixing bed for the covering. They collect the loads the covering sees and deliver them into the frame. Those loads run downward from sheet weight, tiles and foot traffic. They also run upward, from wind trying to peel the roof off. And because they run in straight, evenly spaced rows, they set the plane of the roof. If the battens sit true, the covering reads true from the street.

SEC 02 / Timber vs steel

Timber vs steel battens

Timber built most of the country’s older roofs and still turns up on price alone. The comparison on performance, though, keeps landing the same way.

One honest caveat applies. A steel batten only performs to its span tables when the right section and base metal thickness are chosen. That discipline is exactly what the last section of this guide is about.

SEC 03 / Tile and metal

The roofs they are used on: tile and metal

Under a tile roof, battens are set out to the tile’s gauge. That is the hanging distance each course covers. For common concrete tiles it sits in the low three hundreds of millimetres. The figure is always taken from the tile manufacturer’s tables. Every course of tiles hangs its weight on a batten. So the rows are close together, and the load is constant.

Under sheet metal, the logic flips. The sheeting maker publishes maximum support spacings for each profile and thickness. So battens in roofing that carries corrugated or trapezoidal sheet typically run at wider centres, commonly 600mm to 1200mm. The end spans of a run are held tighter than the internal ones. Our steel roof battens are rolled as a 40mm top hat exactly for this duty. Capacity data is published at the standard spans.

SEC 04 / Choosing right

Why choosing the correct batten is critical

Batten failures are quiet until they are not. An undersized section sags between trusses and telegraphs waves through the sheeting. In a wind event, uplift finds the weakest link. That is often the screw pulling out of a thin supporting member, not the batten itself. That is why capacity gets checked twice. The section is checked against its span table, and the fixing against its pull out table. The lower figure governs.

Getting battens in roofing right costs a few careful minutes with the wind classification and the tables. Getting it wrong costs a re roof. Send us the spans, the sheeting and the wind class, and we will size the section before anything is cut.

SEC 01 / The science

The science behind zincalume coating

It is a metallic coating, hot dipped onto the steel strip before the batten is ever rolled.

The current generation of the coating is an aluminium, zinc and magnesium alloy. It runs at roughly 55 per cent aluminium, with small additions of magnesium and silicon. The balance is zinc. Each metal has a job. Aluminium forms a stable barrier layer. Zinc protects sacrificially, corroding first so the steel does not. Magnesium sharpens that self protection at the places coatings fail first: cut edges, scratches and screw penetrations.

SEC 02 / Vs galvanised

Zincalume vs galvanised steel

Galvanised steel wears a coating of zinc alone, designated with a Z class such as Z275. Zinc’s sacrificial protection is excellent. It is why galvanising has survived for more than a century. The catch is that zinc is consumed as it works. The aluminium rich alloy adds a barrier that is not consumed the same way. In typical open air exposure, a coated sheet of comparable class is generally expected to outlast a galvanised one.

Galvanised still earns its place. It behaves well in contact with fresh concrete and mortar. It also suits some rural and agricultural settings. Those uses keep Z coatings in specifications for good reason. The point is not that one coating is universally better. The alloy coating is simply the modern default for roofing, ceiling and framing components. That is why quality battens are rolled from it.

SEC 03 / Roofs and ceilings

Benefits for roofing and ceiling applications

Battens live in a hard part of the building. A roof cavity cycles from hot and dry to cold and damp overnight. Condensation forms exactly where the battens sit. The alloy coating is built for that duty. It protects through wet and dry cycling and holds up around fastener penetrations. It keeps doing so for decades. There is no rot, no swelling, and no termite exposure of the kind timber battens bring.

That is the material story behind our steel roof battens and steel ceiling battens. Both are rolled from coated G550 high tensile steel, as 40mm and 22mm top hat profiles. The corrosion protection is on the coil before it ever reaches the roll former. Coating class matters more near the coast, where salt loads climb. So do washdown zones. Tell us where the build is and we will talk it through.

SEC 04 / Standards

Australian standards for zincalume products

The governing document is AS 1397, the standard for continuously hot dip metallic coated sheet steel and strip. It covers both the steel base and the coating. Every compliant coil also gets a plain language designation. AS 1397/G550/AM125 means the standard, G550 steel at 550 MPa minimum yield, and an AM coating of at least 125 g/m2.

SEC 05 / Adelaide supply

Sourcing zincalume battens in Adelaide

Kspan rolls battens in Adelaide from coated G550 high tensile steel to AS 1397. The range covers a 22mm ceiling profile and a 40mm roof profile. Lengths run at a standard 6100mm, or as custom runs. The coating class is confirmed on the data sheet for every order. Quotes go out within one business day. Despatch runs across metro and regional South Australia, so the coil to site distance stays short.

SEC 01 / The name

Understanding Wallspan’s product range

First, the untangling, because it saves everyone time.

Wallspan is an Adelaide kitchen and wardrobe company. It designs and installs kitchen renovations and custom wardrobes, including walk in robes and sliding door systems, from showrooms at Gepps Cross, Mile End and Noarlunga. If a new kitchen or robe is what you came for, their showrooms are the right destination, and nothing on this page competes with that work.

Kspan sits on the other side of the plasterboard, literally. We are an Adelaide steel fabricator, and we make top hat battens: the cold formed sections that frame, straighten and carry wall and ceiling linings. Similar name, different trade. If steel for walls is what you were actually after, the rest of this page is for you.

SEC 02 / Wall framing

Using top hat battens for wall framing

A top hat batten is a hat shaped steel section: a flat crown with a web down each side to a fixing flange. On walls it works as a furring channel and girt. Fixed over masonry or an uneven frame, it creates a straight, true plane for lining or cladding, and the crown height opens a cavity behind the skin for services, insulation or drainage.

Both profiles are fabricated in our Adelaide facility from G550 high tensile steel, corrosion treated, in standard 6100mm lengths or custom runs. The full range is on the products page.

SEC 03 / Why steel

Benefits of steel for interior and exterior walls

Walls show every shortcut. Steel battens are dimensionally alike and stay that way: they do not bow, twist, split or creep as moisture moves through the seasons, so the lining fixed to them stays flat and the shadow lines stay honest. Steel is also non combustible as a material, has nothing in it for termites, and handles wet areas and external cavities without the slow movement that timber brings.

SEC 04 / Compliance

Load bearing and compliance information

A batten or girt is a secondary member. It carries the skin: the lining inside, the cladding outside, and the wind load acting on both. The building’s structure still runs through the studs, columns and slabs behind it, so battens are sized from span tables against cladding mass and wind pressure rather than treated as load bearing frame.

SEC 05 / Quotes

Get a quote on steel battens for walls

Send through the wall areas, the lining or cladding type, the cavity depth you need and the lengths involved. We check the section and centres against the load, quote within one business day, and despatch from our Adelaide facility across metro and regional SA. And if it was a robe you were pricing after all, we wish the renovation well.