Damaged Lintels Above Windows & Doors
The horizontal beam above your window or door. When it fails, everything above it starts cracking.
Lintels are the horizontal beams that support brickwork above windows and doors. When steel lintels rust they expand up to 7x their original size, cracking the bricks above and eventually failing structurally. Signs include rust stains on brickwork, cracks radiating from window or door corners, and bulging or bowing brickwork above openings. Proper repair means temporarily propping the load, cutting out the old lintel, installing a new galvanised or stainless steel lintel, and rebuilding the brickwork. Romans Building Services assesses damaged lintels above windows & doors across Sydney before recommending repair, so the visible damage and the cause are both dealt with.
Last updated: 2026-05-29
What is damaged lintels above windows & doors?
A lintel is the horizontal beam that carries the weight of brickwork above a window or door opening. In Australian homes built from 1900 to around 1970, lintels were almost always mild steel — painted once and then forgotten. Steel rusts when exposed to moisture, and when embedded in brickwork it rusts slowly but continuously.
When steel rusts, it expands up to seven times its original volume. That expansion cracks the bricks above the window, pushes the bricks out of line, and eventually causes structural failure. The classic signs are rust stains bleeding down the brickwork, cracks radiating from the corners of window and door openings, and bricks starting to bulge or come loose above the lintel.
Lintel failure is common on Sydney Federation, Interwar and mid-century homes. The good news: it is a contained repair, not whole-house structural work. The bad news: it has to be done properly, with temporary propping, full lintel replacement, and brickwork rebuild. Quick patch jobs always come back.
Signs to look for
- Rust stains bleeding down brickwork from above a window or door
- Cracks radiating from the corners of openings (often stair-step)
- Bricks loose, bulging, or bowing above windows
- Window or door no longer closing properly
- Visible rust on any exposed lintel ends
- Internal cracks in plaster above the opening
- Gaps opening between the lintel and the brickwork
Why it happens
- Steel lintel rusting — moisture reaches the steel through cracks, bad flashing, or masonry porosity
- Salt air accelerating corrosion (coastal suburbs)
- Failed or missing damp-proof course allowing moisture into the lintel
- Original construction without proper rust protection
- Direct water ingress from failed window sills or roof flashing above
- Age — 50+ year old mild steel lintels commonly fail on pre-1970 homes
How urgent is this?
A visibly failing lintel is a structural concern. Eventually the brickwork above the opening can fall — while you do not want to be standing under it when that happens, the more common problem is that once bricks start moving, the repair scope grows fast. Catch it when cracks first appear and the fix is contained. Leave it five years and the whole wall above the window may need rebuilding.
How we fix it properly
Assess and prop
We confirm the lintel is failing, check the extent of brick damage, and install temporary propping to support the load above. Propping stays in place throughout the work.
Remove damaged brickwork
Bricks above the lintel that are cracked, spalled or displaced come out carefully. We salvage what we can for reuse or replacement matching. Goal is clean access to remove the lintel.
Cut out the old lintel
The failed steel lintel is cut out and removed. The bearing points at each end are cleaned back to sound masonry.
Install new lintel
A new lintel — galvanised steel, stainless steel, or precast concrete depending on span and load — is installed with correct bearing at each end and proper DPC to prevent future rusting.
Rebuild brickwork
Matched bricks and lime mortar rebuild the damaged area. Replacement bricks sourced to match colour, size and texture. Pointing matched to surrounding mortar. Done right, the repair is invisible when finished.
Typical cost range
Single lintel replacement typically $1,500 – $4,500 depending on span, access and brick matching requirements. Full facade of multiple failing lintels can run $8,000 – $20,000+.
Every job is different. We give a firm quote after inspection.
Common questions
Why is there rust running down my brickwork above the window?
The steel lintel above the window is rusting. Water has reached the steel — usually through a failed sill, cracked pointing, or general masonry porosity — and the rust is bleeding through to the surface. It means the lintel is deteriorating and needs attention.
Can you just paint over the rust to fix it?
No. The rust is inside the wall, on the lintel. Painting the surface does nothing. And because the steel is expanding as it rusts, cracking bricks from inside, surface treatment is pointless. The lintel has to come out and be replaced.
How long does a lintel replacement take?
Single lintel on a residential property: typically 2–4 days including propping, removal, installation and brick rebuild. Multiple lintels on the same facade can be done together, often 1–2 weeks.
Will the repair be visible?
Done properly, no. Matched brick, matched mortar, matched profile — the repair blends into the surrounding wall. On heritage work we take extra care to match aged brick colour and weathering.
Damaged Lintels Above Windows & Doors in your area
The causes and right fix for damaged lintels above windows & doors vary with local housing stock and exposure. Read the version closest to where you are:
Where we see damaged lintels above windows & doors most often
Some suburbs have more of this problem than others — the local housing stock, age, and coastal exposure all play a part. Click through for the local context.
Think you might have damaged lintels above windows & doors?
Send a photo or call Minas directly. We will tell you straight whether it needs doing now, or whether it can wait.