A wall was opened up, a beam installed, and everything seemed fine when the props came out — but weeks or months later, doors near the new opening start binding and a crack has appeared running across the wall directly above the beam line.
This is not a cosmetic issue and it should not be treated like the finishes problems covered elsewhere in this handbook. It is a structural symptom, meaning the beam or its supports are behaving differently under load than the design assumed, and it needs professional structural input before anything else happens.
What the symptoms are telling you
Doors binding near the opening happen because the frame around them has physically moved out of true as the beam above deflects — even a small amount of deflection is enough to throw a door frame's alignment off. A crack appearing directly over the beam, rather than randomly across the wall, points specifically to that beam line as the source of the movement, not to unrelated general settlement.
Causes, in order of likelihood
There are a limited number of reasons a structural opening deflects after completion, and all of them are matters for structural assessment rather than general building judgement.
- The beam sized without properly allowing for deflection limits under the actual loads above it
- Padstones — the load-spreading pads beneath the beam ends — omitted or undersized for the wall construction
- Props removed before the new beam was confirmed to be fully bearing and taking the load as designed
- The load path from roof or floors above not properly carried down to the foundation through the new arrangement
How to tell the causes apart — and why this isn't a DIY check
Unlike most of the faults in this handbook, this is not a case where a homeowner can reliably narrow down the cause themselves by checking a few visible things. Whether padstones were installed correctly, whether the beam was sized to the actual loading, and whether the load path is properly continuous down to the foundation are all questions that require a structural engineer's calculation and, usually, some opening up to inspect what was actually built.
What a homeowner can usefully do is note whether the movement is ongoing or has stabilised — record the crack width and door clearance over a few weeks — and pass that information to the structural engineer, since it helps establish whether this is a completed, one-off settlement or continuing deflection that needs more urgent attention.
What a survey should record before an engineer visits
Useful preliminary notes for whoever assesses the opening include the exact crack width measured with a simple gauge, the date it was first noticed, and whether any door or window near the opening has become noticeably harder to close over the same period.
It's also worth photographing the crack and door clearance at intervals rather than relying on memory, since a documented rate of change — or the absence of one — is one of the most useful pieces of evidence a structural engineer can be given at the outset.
Why guessing at a fix before assessment makes things worse
Filling the crack or planing the binding door without understanding why the beam is deflecting removes the visible evidence that would otherwise show whether the movement is ongoing, which can delay recognising a worsening structural problem.
Any remedial attempt that adjusts propping, packing or bearings without an engineer's specification risks redistributing load in a way that wasn't calculated, which can affect parts of the structure well beyond the immediate opening.
Common questions
Is this an emergency?+
Ongoing deflection over a structural opening should be treated seriously and assessed promptly. It's not necessarily a sign of imminent failure, but it is a structural matter, and continuing movement needs a structural engineer's judgement on urgency rather than guesswork.
Can I get a builder to just re-support the beam without an engineer?+
No reputable builder should carry out remedial structural work without an engineer's assessment first, because the correct fix depends entirely on why the deflection happened, and guessing at that risks making the problem worse or missing the actual cause.
Will building control need to be involved?+
Very likely, particularly if the original opening required building control sign-off, since remedial structural work of this kind typically needs to be assessed and approved through the same route.
Book a free site visit to scope a structural assessment
We coordinate the structural engineer's assessment first, and only price remedial works once the cause and the fix have been properly established.