If you are considering converting your concrete tile roof to long-run iron, one of the first questions you are likely to ask is – how long will this actually take? And closely behind that comes the equally important question – can I live in my home while it is happening?
The good news is that a tile-to-iron conversion is a well-practised process for an experienced roofing team, and in most cases, your home will be fully weather tight again within a matter of days. Below, we walk through the full process from start to finish, give you a realistic sense of the timeline, and tell you exactly what to expect while the work is underway.
Why Homeowners Choose To Convert From Tiles To Iron
Before getting into the process itself, it helps to understand what the conversion actually involves and why so many homeowners (particularly in earthquake prone areas like Canterbury) are making this switch.
The short answer here is that concrete tiles are heavy. On a standard New Zealand home, a concrete tile roof can weigh anywhere from 40 to 80 kilograms per square metre. Long-run steel roofing, by contrast, typically weighs around 4 to 7 kilograms per square metre. That is a significant reduction in the load placed on your home’s structure.
Beyond the weight factor, concrete tiles are prone to deterioration over time. They crack, shift, and allow moisture to penetrate. Many older tile roofs in New Zealand were also installed without underlay, meaning there is no secondary barrier between your home and the weather if a tile moves or breaks.
Long-run iron, installed over quality underlay, provides a far more reliable weatherproofing system. It is also lower maintenance, lighter, and can significantly improve the thermal performance of your home when paired with appropriate insulation.
The Full Conversion Process Step By Step
1. Initial Assessment And Quoting
A roofing contractor will visit your home, inspect the existing tile roof, assess the condition of the underlying structure, and discuss your material and colour options with you. This is also when any structural concerns are identified, for instance, if the roof framing needs reinforcing or if damaged rafters need attention before the new roof goes on.
At this stage, you will also choose your roofing profile and colour. This matters more than many people expect; the colour of your roof has a significant impact on the overall appearance of your home, so it is worth taking the time to look at samples in natural light and consider how the colour will sit alongside your cladding and joinery.
2. Scaffolding Setup
Before work begins, scaffolding is erected around the perimeter of the roof. This is both a safety requirement and a practical necessity. Expect scaffolding to go up the day before the roofing work starts, or on the morning of day one. The scaffolding will remain in place until the job is complete and the site has been fully cleaned up.
3. Stripping The Tiles
The first major phase is the removal of the existing concrete tiles. This is the loudest and most disruptive part of the entire job. Your roofing team will work methodically across the roof, lifting tiles and passing them down to be sorted at ground level. Tiles are heavy and need to be managed carefully to avoid damage to your spouting, gardens, and driveway.
Once the tiles are stripped, the battens they were sitting on are also removed. At this point, your roof framing (the purlins underneath) is fully exposed. Your roofer will inspect this carefully for any rot, damage, or sections that need repair before proceeding.
Depending on the size of your roof, tile stripping typically takes one to two days for a standard residential home in New Zealand.
4. Structural Repairs And Preparation
If any repairs to the roof framing are needed, this is when they are carried out. In many cases, particularly on older homes, some sections of timber will need replacing. This is not unusual and should be factored into your timeline expectations. Your roofer should flag any likely repairs during the quoting stage, but occasionally additional issues become visible only once the tiles are off. New timber battens are then fixed to the rafters at the correct spacings to suit the chosen roofing profile. This forms the base onto which the new iron will be fixed.
5. Underlay Installation
Quality underlay is installed over the battens before any iron goes on. This is a step that was often skipped on older tile roofs and is one of the reasons those roofs deteriorate. A good underlay provides a secondary weatherproofing barrier, helps manage condensation, and contributes to the acoustic and thermal performance of your new roof.
6. Iron Installation
With the underlay in place, the long-run iron sheets are lifted and fixed to the battens. This is satisfying work to watch. Experienced roofers work efficiently across the roof, overlapping sheets correctly, aligning ridges, and ensuring every fixing is seated properly to prevent future leaks. Depending on the roof’s complexity, including the number of valleys, skylights, chimneys, and penetrations to work around, iron installation on a standard home typically takes one to two days.
7. Flashing, Ridging, And Finishing
Flashings are the metal pieces that seal the joints between your roof iron and any vertical surfaces, penetrations, or changes in roof plane. These include ridge caps along the top of the roof, hip cappings, valley flashings, and any flashings around chimneys or skylights. This is highly skilled work and is where a lot of potential leak points are either correctly sealed or left vulnerable. A good roofer spends as much care on the flashings as on the iron itself. Rushed or poorly fitted flashings are one of the leading causes of roof leaks on otherwise well-installed roofs.
8. Spouting And Downpipes
Most tile-to-iron conversions also involve replacing the existing spouting and downpipes, either because the old system is worn or because the new roofline requires adjustments. New Colorsteel spouting is fitted to complement the new roof, channelling water away from your home’s foundations effectively.
9. Cleanup And Disposal
All old tiles, battens, packaging, and waste materials are removed from site. A professional roofing team leaves your property clean and tidy, including clearing out any debris that has collected in your gutters. This is the final step before scaffolding comes down.
Timeframes – What To Realistically Expect
For a standard single-storey residential home in Christchurch on the flat, for example, a tile-to-iron conversion typically takes three to five working days from scaffolding up to scaffolding down. A larger home, a complex roof with multiple planes, or a job that uncovers significant structural repairs may extend that to a week or slightly beyond.
Here is a rough day-by-day picture for a typical conversion on a medium-sized home:
- Day 1: Scaffolding erected, tile stripping begins
- Day 2: Tile stripping completed, structural inspection, any repairs carried out, battens installed, underlay laid
- Day 3: Iron installation
- Day 4: Flashing, ridging, spouting, and downpipes
- Day 5: Final checks, clean up, scaffolding removed
One thing to note – weather is always a factor in all New Zealand roofing jobs. Your roofer should communicate clearly with you about how any delays due to rain or high winds will affect the schedule, and in turn you should expect delays where the weather turns bad – safety always comes first!
What To Expect While Living In The House
This is the question many homeowners are most concerned about, and understandably so. The short answer is reassuring – in most cases, you can continue living at home throughout the conversion.
- Will It Be Noisy? The biggest day-to-day impact is off course the noise, particularly around the tile removal process. Concrete tiles being lifted and passed down scaffolding, along with the general activity of a roofing team working overhead, means the first day or two will be noticeably loud. If you work from home and need quiet for calls or concentration, it is worth planning around this.
- What About The Dust? Another consideration, particularly on older tile roofs where there can be accumulated grit and debris, dust can be an issue. Luckily most of this stays outside, but some fine dust may enter the roof space. It is worth covering any stored items in the ceiling void if you are concerned.
- What If It Rains? Weather exposure is a key concern for most homeowners, and yes there will typically be a period of hours, rather than days, where some portion of your roof is exposed between the tiles coming off and the underlay going on. Your roofing team manages this carefully, working in sections and always aiming to have the roof weather tight by the end of each working day. A good roofer will always check the forecast and plan accordingly, avoiding stripping more roof than can be covered in a day.
- Will Access To The Driveway Be Restricted? Yes, this may be temporarily restricted as tiles are moved to a skip or trailer. Let your roofer know if you have specific access needs so they can plan around them, or you could think about parking your vehicles out on the street for the day.
- What About The Spouting? Your spouting will be removed and replaced during the job, which means for a day or two you may not have functional guttering. This is standard and your roofer will ensure it is reconnected before leaving site each day if rain is forecast.
How To Choose The Right Roofing Team
A tile-to-iron conversion is not a small job, it requires skill, experience, and proper project management to go smoothly. The timeline estimates above assume you are working with an experienced team that does this type of work regularly, knows how to manage the structural inspection stage, and communicates clearly with you throughout.
Ask your roofer upfront what their process looks like day by day, what happens if they discover structural issues once the tiles come off, and how they handle weather delays. A confident, experienced roofer will have clear answers to all of these questions.
Done well, a tile-to-iron roof conversion is one of the most worthwhile investments you can make in your home. The result is a lighter, warmer, more durable roof that will protect your home for decades to come. If you would like to discuss a tile-to-iron conversion for your Christchurch or Canterbury home, get in touch with the team at Action Reroofing for a free assessment and quote.
