Key takeaways
- Rebedding and pointing is maintenance of the existing ridge and hip bedding on a tiled roof, and should be scoped as a repair to a defined line of tiles rather than as a whole-of-roof re-roof.
- Traditional sand-cement bedding holds the ridge and hip tiles and closes the roof at the junction; flexible pointing is the weather-exposed coating over it, and the two fail in different ways.
- Pointing cracks where the ridge line moves, where bedding was laid too thin or too dry, and where the roof holds water at the junction rather than shedding it.
- Replacing pointing over failed bedding traps the fault underneath, so the bedding must be sounded and rebuilt before any flexible coating goes on.
- Scaffold, safe access and the sequence with other trades are costed into the job from the start, because a return visit to a finished ridge line costs more than the original pointing.
A tiled roof is not a single watertight sheet. It is a set of overlapping tiles, and the places where the roof changes direction — ridges, hips, verges and valleys — are where the system has to be closed by hand. On most tiled roofs in NSW that closure is a mortar bed with the ridge or hip tiles set into it, and a flexible pointing compound travelled over the top.
Both of those materials are wearing items. The bedding is a sand-cement mix that shrinks as it cures and then moves with the roof for the rest of its life. The pointing is a thin, weather-exposed coating that takes the sun, the driving rain and the thermal cycling on behalf of the bedding underneath. When either one fails, water gets into the roof space at exactly the point where the roof is most likely to leak, and the fix is not simply a fresh coat of pointing.
This article is about the repair. New tiled roof work, sarking and underlay installation, and the tie-down of the structure itself sit in separate articles; here the subject is an existing roof that needs its ridge and hip junctions brought back to a serviceable condition, and how to scope, specify and check that work so it is not called back inside a season.
What rebedding and pointing actually covers
Rebedding is the replacement of the mortar bed that holds the ridge and hip tiles and seals the junction between the two roof planes. Pointing is the coating applied over that bed. They are separate operations, done in sequence, and they fail differently.
The bedding does two jobs. It mechanically holds the ridge or hip tile so it cannot lift or slide, and it fills the triangular void between the tiles below and the capping tile above so that wind-driven rain cannot blow straight into the roof space. Traditional bedding is a sand and cement mix, gauged and placed by trowel, with the capping tile pressed into it while it is still plastic.
Pointing is the flexible compound, usually a polymer-modified mortar or an acrylic-based product, travelled over the cured or partially cured bed to form a neat, consistent joint line. Its job is to shed water off the bedding, absorb the small movements at the junction without cracking, and present a clean finish along the ridge.
Because pointing is what you can see, it is what gets quoted. That is the source of most of the trouble with this work: an owner sees cracked and missing pointing, gets three prices for re-pointing, and takes the cheapest. If the bedding under that pointing is drummy, hollow or simply gone, the new coating is a cosmetic skin over a structural gap, and it will crack along the same line within a year or two.
Pointing over failed bedding is the mistake that costs the most. The coating hides the defect, the owner pays twice, and the second visit includes scaffold and strip-out that the first job should have carried.
Reading a roof before you price it
Scope on a rebedding job is decided on the roof, not from the ground and not from a photograph. The useful unit of measurement is the linear run of ridge and hip, broken into sections, with each section marked as sound, cracked, hollow or missing.
Sound the bedding with a hammer or the handle of a trowel. A dull, dead note over a section of ridge means the mortar has separated from the tile beneath, even if the pointing on top still looks intact. That is the section that will fail next, and it belongs in the scope now while the access is set up.
Check the capping tiles themselves. A ridge tile that rocks under light hand pressure is not being held, whatever the bedding looks like. On the hips, look at the bottom end where the hip meets the gutter or the eaves line, because that is where bedding washes out first and where water gets in earliest. On the ridge, look for any low point where water sits on the capping rather than running off, because ponding at the junction is a design and set-out issue that no amount of fresh pointing will fix.
Note the tile profile and colour at the same time. Ridge and hip tiles are matched to the field tile, and on an older roof the profile may no longer be in production. If tiles are going to be broken during strip-out, the owner needs to know before the job starts whether matching stock exists or whether the repair will be visible.
Sequence for a ridge and hip rebedding job
- 1Inspect and mapWalk the roof, sound the bedding along every ridge and hip, and mark each section as sound, cracked or hollow before pricing anything.
- 2Strip the affected sectionRemove the failed ridge or hip tiles and the old bedding, keeping sound tiles for reuse and setting aside broken ones for matching.
- 3RebedLay fresh bedding to the profile and thickness the tile manufacturer requires, working in runs short enough that the mortar does not cure before the tile is set.
- 4PointApply the flexible pointing product over cured bedding to the supplier’s stated thickness and profile, keeping the joint line consistent.
- 5Clean downRemove mortar smear from tile faces and gutters before it sets hard, and check that the ridge line drains rather than ponding.
Materials: the bed, the coating and what they must do
The bedding mix is specified by the ridge tile manufacturer or the mortar supplier, and the mix proportions, the addition of any bonding agent, and the required bedding thickness all come from that source. Do not substitute a stronger or richer mix on the assumption that harder is better. A mix that is too rich shrinks more as it cures, and shrinkage cracking in the bed is one of the common causes of the pointing above it splitting.
Flexible pointing products are similarly product-specific. The supplier states the surface preparation required, the minimum and maximum thickness, the working time, and the conditions the product can be applied in. Those figures matter, and they are on the product data sheet rather than in this article. Get the current sheet before you specify, because the formulations change and an old habit may not match the current product.
Two material decisions drive most of the durability of the finished job. The first is whether the bedding is placed wet enough to bond but firm enough to hold the tile without slumping; a dry, crumbly mix that is trowelled into place will not key to the tile or to the bed below. The second is whether the pointing is applied over bedding that has cured enough to take it but not so much that the surface is sealed and dusty; a coating applied onto a dry, dusty bed sits on top rather than bonding, and lifts at the edges.
Where the roof is in a coastal or high-wind area, the exposure at the ridge is greater and the junction takes more driving rain. That does not change the products, but it raises the standard of workmanship: the bed has to be full and the pointing continuous, because a gap of even a small dimension at the ridge is an entry point for water under wind pressure.
Why pointing cracks, and what the crack is telling you
Pointing cracks for reasons that are readable, and each pattern points to a different cause.
A single long crack running along the length of the ridge, roughly parallel to the capping tile, usually means movement. The ridge line is the highest and most exposed part of the roof, and it moves with thermal cycling and with any movement in the structure below. If the bedding is rigid and the coating is thin, the coating takes the strain and splits. A coating with the right flexibility tolerates that movement; a coating applied too thin does not.
Cracking concentrated at the joints between individual capping tiles, or at the change in direction where a hip meets a ridge, points to the bedding. At those locations the bed has to accommodate two different tile orientations, and if it is too thin or has been feathered out, there is nothing behind the coating to support it.
Pointing that has lifted away from the bedding edge, rather than cracked through, usually means a bonding failure. The common causes are a dusty or contaminated bed, application outside the product’s stated conditions, or application over a bed that had already been coated with something else. Once the coating has separated at the edge, water gets behind it and the whole run is compromised.
Erosion, chalking and a washed-out appearance on the weather face is normal ageing of the coating, and it tells you the pointing has reached the end of its service life. That is the one case where a re-point over sound bedding is the correct scope, provided the bedding is sounded and confirmed.
Bedding faults against pointing faults
| Bedding fault | Pointing fault |
|---|---|
| Hollow or drummy mortar under the ridge tile | Cracked or crazed surface coating |
| Ridge tile sitting loose or rocking | Coating lifting away from the bedding edge |
| Bedding washed out at the eaves end of a hip | Coating chalky or eroded on the weather face |
| Visible gap at the tile-to-bedding junction | Coating split where the ridge line changes direction |
Access, sequence and the trades around you
Almost every rebedding and pointing job needs edge protection or scaffold along the elevation being worked. On a two-storey roof the access cost is a substantial part of the price, and it is the reason a cheap quote and a thorough quote can look so different on paper. The quote that omits adequate access is not cheaper; it is a job that will be done from a ladder or a harness in a way that produces worse work and a higher risk of a fall.
Sequence the work with the other trades on site. If gutters are being replaced, do the gutter work first so the roof work does not have to be redone around new gutter. If the roof space is being used for anything — a renovation, a new service run — the ceiling and the roof cavity should be clear before the ridge line is opened up, because opening the ridge leaves the roof space exposed to rain until the bedding is back in.
Weather matters more on this job than on most. Fresh bedding and freshly applied pointing both need conditions within the product’s stated range, and a ridge line that is rained on before the coating has set will need to be stripped and redone. Build in the ability to stop and cover; a tarp over an open ridge is cheaper than a rebuild.
Where the work is part of a larger renovation and the roof structure itself is being altered, the roof covering and its junctions are only one part of a set of requirements. The checks on roof truss bracing and tie-down cover the structure that the tiles sit on, and the sarking and roof underlay article covers the layer beneath the tiles. Rebedding assumes both of those are already adequate.
Water, condensation and the roof space underneath
Stopping water at the ridge is only half of the moisture story. A tiled roof over a ventilated roof space manages moisture by letting the space breathe, and the ridge and hip junctions are part of how that works. When the bedding is replaced with a solid, well-sealed bed and the pointing is continuous, the roof space below is more closed than it was, and the way moisture leaves the roof space changes.
The Condensation in buildings handbook published by the Australian Building Codes Board sets out how moisture moves through a building and how ventilation and vapour management interact. The point for a roofing repair is that sealing one path does not create a problem on its own, but it does change the balance. If the roof space was relying on air movement through a deteriorated ridge line to dry out, the new work closes that path and any other moisture source in the roof space — a bathroom exhaust discharging into the cavity, a leaking pipe, a downlight penetration — becomes more significant.
Roof ventilation at the ridge is sometimes provided deliberately, through a ventilated ridge system rather than a solid mortar bed. If the roof you are working on has a ventilated ridge, replacing it with a solid bed changes the design intent. Check what is actually there before stripping, and if the roof has a ventilated ridge system, replace like with like or confirm the alternative ventilation is adequate.
Where this fits in the broader compliance picture
Rebedding and pointing on an existing dwelling is maintenance, not new construction, and it does not usually trigger a development application. It can, however, sit inside a larger project that does. If the roof work is part of an alteration or addition, or part of a change of use, the approval pathway for the project as a whole applies, and the roof repair is one line in a broader scope.
Where the project involves a new dwelling or a substantial rebuild, the energy and water requirements for the development are assessed through BASIX, which is administered through the NSW Planning Portal. Roofing choices, including insulation and ventilation, feed into that assessment. On a straight repair job none of that applies, but it is worth knowing where the boundary sits, because owners often assume a repair quote covers a change they have not yet had approved.
Modern methods of construction, described by the NSW Department of Planning, Housing and Infrastructure, are changing how some roofs are assembled, with prefabricated and panelised systems becoming more common in new work. Those systems have their own junction details and their own maintenance requirements, and the traditional mortar bed and flexible pointing approach does not automatically transfer to them. If you are repairing a roof built with a prefabricated system, get the system documentation before you touch it.
For builders keeping their knowledge current across these areas, the PointCPD guide to how NSW builder CPD works explains the categories and the record-keeping, and the course catalogue lists what is available.
Worked example: a ridge line on a western Sydney roof
A builder in western Sydney is asked to quote on a tiled roof where the owner has noticed cracked pointing along the main ridge. The house is a single-storey brick veneer, the roof is a conventional tiled roof with a mortar bed at the ridge, and the owner has two other quotes, both of which describe the work as re-pointing.
The builder gets on the roof and sounds the ridge. About half the run gives a dead, hollow note, and several capping tiles rock when pressed. The pointing is cracked along the length of the ridge and has lifted at the edge on the western side, which faces the prevailing weather. At the base of the hips, the bedding has washed out and there is a visible gap. The field tiles are sound, the sarking beneath is intact, and there is no evidence of a leak into the ceiling space.
The scope the builder prices is not re-pointing. It is strip and rebed of the affected ridge sections and the hip bases, with re-pointing over the full ridge and hip run so the finished line is consistent. The quote separates the access, the strip-out, the bedding, the pointing and the disposal, and it notes that a small number of capping tiles may break during strip-out and that matching replacements may need to be sourced.
One of the competing quotes is lower because it allows only for cleaning and re-pointing over the existing bed. If the owner accepts that quote, the hollow bedding stays in place, the new coating cracks along the same lines within a season, and the second repair carries the scaffold cost again. The builder who sounded the roof is not the expensive option; the builder who skipped that step is the one whose price was never real.
Checking the work before you hand it back
Walk the finished ridge and hip line and check the things that predict whether you will be called back.
- Sound the new bedding. It should give a solid note along the whole run, with no drummy sections.
- Press each capping tile. Nothing should rock or lift.
- Check the pointing profile for consistency and confirm it has been applied at the thickness the product requires, not feathered out to look neat.
- Look for cracks, especially at the joints between capping tiles and at the change of direction where hips meet the ridge.
- Confirm the junction drains. Water should run off the ridge and hip line, not sit on it.
- Clean the tile faces and the gutters of mortar smear before it cures hard.
- Confirm the roof space below the work is dry and that no bedding or debris has fallen into the ceiling void.
Document the finished work with photographs along the ridge and hips. On a repair like this, the record of what was found and what was replaced is the difference between a maintenance history and an argument.
Rebedding and pointing is straightforward work done badly more often than almost anything else on a residential roof, because the visible half of it is easy to sell and the invisible half is easy to skip. Sound the bed, scope the line, use the products as the manufacturer states, and the repair will outlast the coating that prompted the call in the first place.
Questions builders ask
How do I tell whether a roof needs re-pointing or full rebedding?
Sound the bedding along the ridge and hip runs with a hammer or trowel handle. A solid note means the bed is holding and a re-point over sound bedding is the correct scope. A dead or hollow note means the mortar has separated from the tile and the section needs to be stripped and rebedded before any coating goes on.
Why does new pointing crack within a year?
The usual cause is that the pointing was applied over bedding that had already failed or was still moving, so the coating took strain it was never designed to carry. Applying the product too thin, or onto a dusty or damp bed outside the supplier’s stated conditions, produces the same result. The crack pattern tells you which: a long crack parallel to the capping tile suggests movement, while cracking at tile joints points to the bedding underneath.
Can I re-point over the top of the old pointing?
Generally no. A new coating over an old one bonds to the old coating, not to the bedding, and the old coating is already the weak layer. The supplier’s data sheet will state the surface preparation required, and that is the document to work from rather than a general rule.
Does a ventilated ridge change how I repair the roof?
Yes. If the roof has a ventilated ridge system rather than a solid mortar bed, replacing it with a solid bed changes the design intent and alters how the roof space manages moisture. Confirm what is actually there before stripping, and either replace like with like or verify that the alternative ventilation is adequate for the roof space.
What access do I need for ridge and hip work?
Most single and two-storey jobs need edge protection or scaffold along the elevation being worked, and that cost belongs in the quote. Working from a ladder or relying on a harness alone limits how well the bedding can be placed and increases the risk of a fall. The access requirement is set by the site conditions and the relevant safe work guidance, not by what the last job used.
How does a rebedding job interact with condensation in the roof space?
Sealing the ridge line closes one path for air movement through the roof space, which changes the moisture balance rather than creating a problem on its own. Any other moisture source in the cavity, such as an exhaust discharging into the roof space or a leaking service, becomes more significant once that path is closed. The Australian Building Codes Board condensation handbook is the reference for how moisture moves through the building.
Sources
- Modern methods of construction · NSW Department of Planning, Housing and Infrastructure
- Modern methods of construction · NSW Department of Planning, Housing and Infrastructure
- BASIX · NSW Planning Portal
- Condensation in buildings handbook · Australian Building Codes Board
Published 22 July 2026. General information for builders, not legal, financial or engineering advice for a specific job. Check current requirements with the relevant regulator or standard before relying on them.
