How to Hang Curtains and Blinds Straight on Plasterboard
Right, here’s the thing. I hung close to two thousand curtain rods and blinds over my 25 years on the tools and I can tell you the laser level you bought at Bunnings last weekend is lying to you. Not because it’s broken. Because the ceiling above it is wonky. Aussie houses — even the brand-new house-and-land jobs out at Cameron Park — almost never have a level ceiling. The cornice runs uphill, the bulkhead drops 4 mm over a metre, and your eye reads the whole wall against that ceiling line. So you set your laser perfectly level, mount the rod, hang the curtains, and they look crooked anyway. I had a customer in Merewether last year accuse me of being half-pissed when I hung her curtains — the rod was dead level on a 1.2 m level, but it looked sloped because her cornice dropped 8 mm across the window opening.
The fix is what I call the “two pencil dots and a string” method. Takes 90 seconds, costs nothing, and makes the rod look right against whatever the ceiling is actually doing. Most of the YouTube blokes teach the wrong technique because they’re working in American plasterboard offices with proper square ceilings. Aussie homes are different. The other reason this article exists: most blockout curtain installs I get called back to fix were never going to last. Generic plastic anchor in the Gyprock, hang 8 kg of fabric off it, and within a year it’s pulled out, taking a 50 mm crater of plasterboard with it. We’re going to fix that for good.
What you’ll need
- Stanley FatMax 5 m tape measure
- HB pencil — sharp, not the chewed stub in the drawer
- Roll of mason’s line or any string about 1.5 m long
- Stud finder — Stanley S100 minimum, Bosch GMS 120 if you want to spend a bit
- Cordless drill with PH2 bit and a 3 mm pilot drill (Ryobi One+ or similar)
- Spirit level — 600 mm minimum, the little 200 mm torpedoes are useless for curtain rods
- Hangman snap-toggle anchors (22 kg rated into Gyprock) OR Toggler SnapSkru SP for lighter loads
- Curtain rod brackets and 35 mm × 8g countersunk timber screws for studs
- Stepladder, not a kitchen chair
Step 1: Decide the height before you touch the wall
Standard rule: 150 mm above the window architrave, or halfway between architrave and cornice if that gap is under 300 mm. For floor-to-ceiling drama (which is what most of my clients want now), go right up to within 50 mm of the cornice. Whatever you choose, write it down — left side height and right side height — because you’re definately going to forget by the time you’re up the ladder. Why the height matters: too low and the curtains look stumpy, too high and the eye sees the wall above the rod and the whole window looks shrunk.
Step 2: Find the studs first, position the rod second
This is where 99% of installs go wrong. People decide where the brackets go, then drill, then discover they’ve missed the stud by 40 mm. Now they’re committed and the toggle anchors are doing all the work. Run the stud finder along the full width of the window plus 200 mm either side. Mark every stud edge with a pencil tick. Aussie stud spacing is 450 mm or 600 mm centres — but in older Newcastle weatherboard homes I’ve seen everything from 380 to 720, so don’t assume. If you want the deep dive on tracking down studs reliably, have a read of how to use a stud finder properly — it’ll save you a couple of patched holes.
Step 3: The two pencil dots
Mark your bracket centre on the left at the height you decided. Now measure across to the right side and put a pencil dot at the same height. Don’t level it yet. Just match the height off the floor — measure from the floor on both sides, not from the cornice. The reason: floors are usually more level than ceilings (the slab was poured level once, cornices drift). Why is this counter-intuitive? Most blokes naturally measure down from the ceiling because the ceiling looks like a reference. It’s not.
Step 4: The string trick
Stretch your mason’s line tight between the two pencil dots. Now stand back three metres and look. If the string runs parallel to the top of the architrave (and roughly parallel to the cornice), you’re done — that’s your line. If it looks crooked because the floor slopes too, split the difference: nudge one dot up or down 2-3 mm until the string looks right against both the architrave and the cornice. Your eye is the final judge, not the spirit level. The string IS the level for this job because it averages out the room’s wonkiness. Fair dinkum, this is the single best technique I’ve learned in 25 years and they don’t teach it on YouTube.
Step 5: Transfer to bracket positions
With the string still in place, mark the bracket screw positions. For a standard double rod bracket you’ve got two or three screw holes per bracket. Goal: at least one screw per bracket lands in a stud. If both can hit the stud, even better. If neither can — because your window is positioned between studs — that’s where the Hangman toggles come in (Step 7).
Step 6: Pilot drill (don’t skip this)
3 mm pilot hole, 30 mm deep, into every screw position going into a stud. Pilot holes stop the screw from snaking sideways through the soft pine and pulling the bracket off-true. For Gyprock-only positions where you’ll use toggles, drill the size the toggle packet specifies — Hangman snap-toggles want 13 mm, Togglers want 8 mm. Wrong hole size and the toggle won’t deploy properly behind the plasterboard.
Step 7: Toggles for the no-stud positions
Here’s where the Aussie gotcha bites the US-tutorial crowd. American drywall is denser and 12.7 mm thick. Aussie Gyprock is 10 mm in most homes (13 mm in wet areas) and softer. A US “drywall anchor” rated 5 kg holds about 2 kg in Gyprock before the paper tears. For any blockout curtain over 4 kg total weight, use a Hangman snap-toggle (rated 22 kg in 10 mm Gyprock) or a Toggler SnapSkru SP. Avoid the brittle plastic expansion plugs — they’re for picture frames, not curtains. Don’t be that bloke who uses the generic plug and gets a callback in 6 months.
Step 8: Mount the brackets and check with the long level
Drive the screws to firm — not gorilla-tight. With clip-on brackets you’ll feel them seat. Now lay your 600 mm spirit level across the tops of both brackets. It probably won’t read dead level, and that’s fine — you levelled to the room, not to gravity. Hang the rod and step back. If it looks straight against the architrave and the cornice, the job is right.
Step 9: Hang and adjust the curtains
Put the curtains up before you finish tightening everything. Sometimes the weight pulls the rod down 1-2 mm at a bracket and you’ll want to nudge a screw. Better to find that now than in six months when one side has sagged and your customer is asking pointed questions.
Step 10: The 24-hour test
I always tell clients: open and close the curtains hard ten times the next day. If the brackets feel tight and the rod hasn’t shifted, you’re done. If anything has moved, it’s a stud miss or an under-spec’d anchor — fix it now before the kids start swinging on the curtains. While you’ve got the drill out, the same stud-first approach applies to mounting a TV on plasterboard or installing a floating shelf properly — both use the same anchoring decision tree.
When to call a tradie
Listen mate, most curtain installs are within homeowner skill. Where I’d call someone: motorised curtain tracks (the wiring needs a licensed sparky, no exceptions — fixed wiring is licensed work under AS/NZS 3000), brick veneer walls where the stud is impossible to reach and you need brick-fix anchors, or heritage homes with lath-and-plaster ceilings where modern toggles tear the plaster apart. For lath and plaster, get a plasterer to give an opinion before you start drilling — your one missed hole becomes a 200 mm crack.
Common screw-ups
- Brass screw shears off in the bracket. Cheap brass screws will snap at 1.5 Nm. Use the cordless on clutch setting 5 max, or hand-finish the last few turns.
- Bracket spins free under load. You missed the stud and the toggle didn’t deploy. Re-drill to the toggle’s exact spec size.
- Rod sags in the middle. Long rods over 2 m need a centre bracket. Don’t rely on two end brackets for a 3 m span.
- Eyelet curtains binding. Eyelet inner diameter needs to be 5 mm bigger than the rod, or they snag every draw.
- Levelled to the laser, looks crooked. Always level to the room (the string trick), never to gravity alone.
Cost & time
A pair of decent brackets and a rod from Bunnings or Spotlight runs $35-120 depending on length and finish. Hangman snap-toggles are about $1.50 each in a 4-pack. Time: 45 minutes for a single window if you’ve already got the tools, 90 minutes for a tricky double rod or a bay window. Less than the call-out fee for a tradie, and you’ll have the skill for the next 20 windows in your life.
The Mick wrap
Level the rod to the room, not to gravity. The string between two equal-height pencil dots beats a laser level every time in an Aussie house — your eye reads the rod against the cornice and architrave, not against an invisible horizontal plane. And if you can’t hit a stud, spend the extra two bucks on a Hangman snap-toggle. Generic plastic plugs in Gyprock are the reason I get callbacks. Get those two things right and the curtains will hang straight for the next two owners of the house.
