Framing accurate door rough openings during first-fix timber framing is essential for hanging doors smoothly without binding or requiring excessive packing. Use this comprehensive guide and sizing tables to determine exact stud-to-stud framing clearances, cavity pocket requirements, and AS 1684 structural member lengths for Australian residential projects.
What Is a Door Rough Opening in Australian Framing?
In Australian residential carpentry, a door rough opening (often called the stud opening or framed opening) is the structural timber opening created during first-fix framing to accept a pre-hung door frame or loose jamb set.
The rough opening must always be larger than the physical door leaf. It must accommodate the thickness of both timber jamb legs (typically 19mm primed pine), the operating margins between the door and frame (3mm perimeter gaps), finished floor level (FFL) build-up, and sufficient plumbing clearance for plastic horseshoe packers.
If your rough opening is framed too tight, you will not be able to plumb the jamb on out-of-square studs. If it is framed too wide, standard 67mm or 42mm architraves will fail to cover the gap between the timber jamb and the surrounding plasterboard.
Australian Standard Door Sizes & Stud Opening Chart
Australian door manufacturers (primarily Hume Doors and Corinthian Doors) manufacture internal and entrance doors in standardised metric dimensions. The table below lists standard door sizes with their corresponding rough opening and clear passage dimensions:
| Application / Room Type | Door Leaf Size ($W \times H$) | Stud Rough Opening | Outside Frame Size | Clear Passage Width |
|---|---|---|---|---|
| Small Linen / Broom Cupboard | 520 × 2040 mm | 580 × 2100 mm | 564 × 2074 mm | 473 mm |
| Wardrobe / Cupboard | 620 × 2040 mm | 680 × 2100 mm | 664 × 2074 mm | 573 mm |
| Pantry / Ensuite / Powder Room | 720 × 2040 mm | 780 × 2100 mm | 764 × 2074 mm | 673 mm |
| Standard Internal Passage | 820 × 2040 mm | 880 × 2100 mm | 864 × 2074 mm | 773 mm |
| Wide Internal / Front Entry | 870 × 2040 mm | 930 × 2100 mm | 914 × 2074 mm | 823 mm |
| AS 1428.1 Wheelchair Accessible | 920 × 2040 mm | 980 × 2100 mm | 964 × 2074 mm | 873 mm (Passes ≥850mm) |
| High Ceiling Passage (2.7m/3.0m) | 820 × 2340 mm | 880 × 2400 mm | 864 × 2374 mm | 773 mm |
| High Ceiling Entry Door | 870 × 2340 mm | 930 × 2400 mm | 914 × 2374 mm | 823 mm |
For wall framing schedules and overall stud layouts across an entire project, refer to our Wall Framing Calculator to calculate studs, noggings, and bottom plates.
The +60mm Rule: Clearance Breakdown
The universally accepted rule of thumb among Aussie chippies is to frame rough openings 60mm wider and 60mm higher than the door leaf. Here is the exact millimeter breakdown of how that 60mm clearance is consumed during second-fix installation:
Rough Opening Width Formula (Hinged Door):
Rough Width = Door Width + (2 × Jamb Thickness) + (2 × Door Margins) + (2 × Packing Gap) Example for 820mm door: 820 + (2 × 19mm) + (2 × 3mm) + (2 × 8mm) = 880 mm
Rough Opening Height Formula (Hinged Door):
Rough Height = Door Height + Head Jamb Thickness + Top Door Gap + Floor Clearance + Head Packing Gap Example for 2040mm door: 2040 + 19mm + 3mm + 15mm (FFL) + 23mm = 2100 mm
- Jamb Thickness (38mm total): Standard pine jamb legs are 19mm thick each (left and right).
- Operating Margins (6mm total): A 3mm clearance gap is required on both hinge and latch sides so the door swings smoothly without binding.
- Packing & Plumbing Allowance (16mm total): Leaves ~8mm on each side for sliding plastic packers and leveling the jamb against uneven wall studs.
- Floor Clearance (15mm): Allows the bottom edge of the door to swing freely over carpet underlay or tile transition angles.
Cavity Sliding Pocket Door Framing Specs
Cavity sliding doors (pocket doors) do not follow the standard +60mm rule because the timber pocket unit and aluminium top track assembly require extra structural width and head height.
Standard Australian cavity units (manufactured by Hume, Corinthian, and CS Cavity Sliders) require the following stud rough openings:
Cavity Slider Rough Opening Formulas:
Rough Width = (Door Leaf Width × 2) + 20 mmRough Height = Door Leaf Height + 90 mmExamples for standard cavity slider openings:
- 720 × 2040 mm door: Requires a
1460 × 2130 mmstud rough opening. - 820 × 2040 mm door: Requires a
1660 × 2130 mmstud rough opening. - 870 × 2040 mm door: Requires a
1760 × 2130 mmstud rough opening.
Because cavity sliders create a wide unsupported span in the wall frame (e.g. 1660mm wide for an 820mm door), they require structural lintel sizing. Use our Lintel Calculator to verify header beam spans under AS 1684.
Door Jamb Profiles & Wall Depth Matching
Selecting the correct jamb width is critical during first-fix framing so that the jamb edges finish exactly flush with the lined plasterboard surface on both sides of the wall.
| Wall Framing Type | Plasterboard Lining | Required Jamb Width | Standard Profile |
|---|---|---|---|
| 90 × 45 mm Studs (Standard External & Internal) | 10mm plasterboard (each side) | 110 mm | 110 × 19mm Single Rebated Pine |
| 70 × 35 mm Studs (Internal Partitions) | 10mm plasterboard (each side) | 90 mm | 90 × 19mm Single Rebated Pine |
| 140 × 45 mm Studs (Acoustic / Plumbing Wall) | 10mm plasterboard (each side) | 160 mm | 160 × 19mm or 160 × 30mm Custom Jamb |
| 90 × 45 mm Studs (Acoustic 13mm Soundstop) | 13mm Soundstop (each side) | 116 mm | 116 × 19mm Machined Pine |
Single Rebated vs Flat Jamb with Planted Stop
Single Rebated Jambs have a 38mm wide × 12mm deep rebate pre-machined into the solid timber. They provide maximum strength and clean sightlines, making them the default choice across Australian residential construction.
Flat Jambs with Planted Stops use a flat 19mm board where a separate 30×12mm stop bead is tacked into position on-site. They allow on-site adjustment if the door leaf has slight bow or if custom door seals are installed.
AS 1684 Jack Studs, King Studs & Lintel Support
Under AS 1684 (Residential timber-framed construction), every door opening penetrating a load-bearing wall must have properly designed timber framing members to transfer vertical and lateral loads:
- Jack Studs (Trimmers): These vertical studs sit directly under the ends of the lintel header. They transfer roof and upper-floor loads from the lintel down to the bottom plate and subfloor. The cut height of a jack stud is equal to the rough opening height minus the bottom plate thickness (45mm).
- King Studs: These are full-height studs placed immediately alongside the jack studs, running continuously from the bottom plate to the underside of the double top plate. They provide lateral restraint against wind pressures and door slamming vibrations.
- Lintel Header: The horizontal timber beam spanning the rough opening width. The minimum lintel span must equal the rough opening width plus the thickness of the supporting jack studs (e.g. 880mm + (2 × 45mm) = 970mm).
For heavy tile roofs or girder truss point loads sitting above the door opening, verify span tables with our Timber Span Calculator.
Jobsite Checklist & Common Framing Pitfalls
Avoid these costly on-site framing mistakes during first-fix framing:
- Forgetting Floor Level Build-Up (FFL): If you frame the door opening to 2100mm directly off a bare concrete slab, and the owner later installs 18mm hybrid timber flooring on underlay, your effective door opening height drops to 2082mm, forcing you to undercut the door leaf. Always check architectural FFL details before cutting jack studs.
- Bowed Jack Studs: If you use crown-in or bowed framing timber for jack studs, the timber can bow inward and pinch the door jamb. Always select straight MGP10 studs for opening trimmers.
- Failing Diagonal Squareness: Always cross-measure the diagonals of the framed opening before fixing king studs. A difference greater than 3mm means the opening is out of square and will make hanging pre-hung doors frustratingly slow.
- Missing Double Jack Studs on Sliders: Cavity sliders and wide openings exceeding 1200mm span require double jack studs (2 trimmers under each lintel end) to prevent excessive deflection under live roof loads.