True roof area worked from the pitch, not the plan view. Sheets cut to length, tiles counted, and every metre of ridge, valley, barge, gutter and flashing measured on its own line.
A roof measured in plan view is always smaller than the roof you have to cover. At 22.5 degrees you are about eight per cent short; at 30 degrees around fifteen. On a big roof that is a real quantity of material and a real hole in the quote.
We take the pitch off the elevations, convert every plane to its true area, and then measure the linear items separately — because on most roofs the flashing, gutter and capping metres carry as much labour as the sheeting does.
Each roof plane is measured individually and converted to true area using its pitch. Hips, valleys and ridges are measured to their true lengths, which are longer again than either the plan length or the rafter length.
For metal roofing we produce a sheet schedule: cut lengths by run, with the profile and finish from the specification, plus fixings, closures and sarking area. Standard-length ordering versus cut-to-length is called out, since it changes both waste and lead time.
For tile roofing we count tiles by type, including ridge and hip tiles by the metre, plus bedding and pointing, sarking, battens and valley irons. Either way, gutter, fascia, downpipes, flashings and penetrations are measured as their own lines.
Nothing here is an allowance. Each line is measured off your drawings in its own unit, so you can check it against the plan yourself.
| Item | How it is measured | Why it matters |
|---|---|---|
| True roof area | Each plane measured and converted from plan area using its pitch | This one conversion is the difference between a right quote and a short one |
| Sheets or tiles | Sheet cut lengths by run, or tile counts by type, plus waste | A sheet schedule lets you order cut-to-length instead of paying for offcuts |
| Ridge and hip | True linear metres, with capping or ridge tiles and bedding | Hip and ridge metres are longer than they look in plan, on every roof |
| Valleys | True linear metres, plus valley irons or gutters and sarking | Valleys are slow, detailed work and belong on their own line |
| Barge and fascia | Linear metres by profile | Easy to measure, easy to forget, and always visible when it is missing |
| Gutter and downpipes | Gutter metres by profile, downpipe count and drop lengths | Downpipe lengths come off the elevations, not the roof plan |
| Flashings | Linear metres by type — apron, step, sill, wall and parapet | Flashing metres are labour-heavy relative to their material cost |
| Penetrations | Counted individually: vents, whirlybirds, skylights, flues, solar | Each one is a detail, a flashing and a labour item |
| Safety and access | Edge protection metres, scaffold and roof anchor requirements | A code requirement with real cost, and never inside a per-square-metre rate |
| Pitch | Approximate factor on plan area | Effect |
|---|---|---|
| 15° | About 1.04 | Roughly 4% more material than the plan suggests |
| 22.5° | About 1.08 | Roughly 8% more — the common metal roof pitch |
| 25° | About 1.10 | Around 10% more |
| 30° | About 1.15 | Around 15% more — common on tiled roofs |
| 35° | About 1.22 | Over 20% more, plus slower and less safe access |
| 45° | About 1.41 | Over 40% more, and effectively a different job to install |
A simple gable roof cuts almost no waste on sheeting. A hipped roof with three valleys and a dormer cuts a lot, because every sheet meeting a hip or valley is a raking cut. We set the waste allowance from the roof geometry rather than applying a flat percentage.
Tiles behave the same way. Cutting into valleys and around penetrations breaks tiles, so the allowance goes up on a cut-up roof and stays low on a straightforward one.
The same five steps on every job, whether it is a single slab or a full tender package.
Email the architectural and structural drawings, the specification and the scope of works in whatever format you have — PDF, DWG, or photos of a marked-up set. If something is missing we will tell you before we start, not after.
Each roof plane is measured individually and converted to true area using its pitch. Hips, valleys and ridges are measured to their true lengths, which are longer again than either the plan length or the rafter length.
Every measured item gets its own colour and legend entry on the drawing. When the takeoff comes back you can see exactly what was counted and what was not, so you are never asked to trust a number you cannot trace. This is the part clients tell us they did not know they needed until they had it.
The takeoff is delivered as a working spreadsheet, not a locked PDF. Your rates sit in their own column, so you can change a supply price or a labour rate and watch the total move. Plug in your own numbers and the sheet is yours to reuse on the next job.
Quantities are re-measured independently and cross-checked against the drawing before anything leaves here. You get the marked-up plans, the priced spreadsheet and a plain-English note on anything we flagged as unclear or excluded.
The takeoff arrives as a live Excel spreadsheet with the colour-coded marked-up plans beside it. Your rates go in your own column, so you can plug in your own supply and labour numbers and reuse the sheet on the next job. Nothing is locked.
First estimate free. After that the fee is confirmed in writing as a fixed amount before any work starts. No retainer, no subscription, no lock-in contract. Full pricing detail here →
Wind classification changes the fixing schedule, and the fixing schedule changes both the screw count and the labour. A coastal or high-wind site can carry substantially more fixings per square metre than a sheltered one.
Coastal exposure also drives the material specification — the corrosion environment decides which coating or substrate is acceptable, and the difference in supply price is significant. We work to the specified product rather than the cheapest equivalent, and note where the spec leaves it open.
Quantities are measured against the standards and the specification for your job. Where a drawing and a standard disagree, we flag it rather than quietly picking one.
| Standard | Covers | Relevance |
|---|---|---|
| AS 1562 | Design and installation of sheet roof and wall cladding | Metal roofing installation |
| AS 2050 | Installation of roof tiles | Tile fixing and flashing requirements |
| AS/NZS 3500.3 | Plumbing and drainage — stormwater drainage | Gutter and downpipe sizing |
| AS 4055 | Wind loads for housing | Fixing schedule and wind classification |
None of these are unusual. They are the things that get missed when a quote is put together at 9pm after a full day on the tools.
If your question is not here, email it through and you will get a straight answer, not a sales call.
Each roof plane is measured in plan and then converted using its pitch, taken off the elevations or the sections. Hips, valleys and ridges are measured to their true lengths separately.
The marked-up drawings show each plane with its own colour and its own area, so you can check the total against the roof before you order.
Yes — cut lengths by run, with the profile and finish from the specification, plus fixings, closures and sarking. That lets you order cut-to-length rather than paying for offcuts, which on a large roof is a meaningful saving.
Yes. Tile counts by type with waste, ridge and hip tiles by the metre, bedding and pointing, sarking, battens and valley irons. Concrete and terracotta are priced as specified rather than interchangeably.
All of them, each on its own line. Gutter and fascia by the metre by profile, downpipes counted with their drop lengths off the elevations, and flashings by type. On many roofs the linear items carry as much labour as the sheeting.
Edge protection metres, scaffold and any roof anchor requirements are listed as separate items with the extent they cover. They are a legal requirement and a real cost, and they never belong inside a square metre rate.
A roof plan, the elevations and the sections, plus the specification for the profile, finish and fixing requirements. If there is no roof plan we can work from the architectural set, and we will note the pitch we have used so you can confirm it.
Most residential roofs come back within 24 hours of the plans arriving. Large commercial or industrial roofs take longer because there are more planes and more detail — we confirm the timing before starting.
Most jobs cross more than one trade. We can price the whole package in one spreadsheet.
Your first estimate is free. Email the drawings and the scope, and you will have a marked-up takeoff and a priced spreadsheet back within 24 hours on most residential jobs. Prefer to talk first? Reply with "KEEN" and your number.