What a Plastered Wall Can Hide: Three Building Mistakes Worth Checking For

A standard wall needs to be vertical and level, which takes time and constant checking. On a stock brick wall, a lean of 10mm to 15mm over a two-metre height can be corrected later by applying a thicker plaster layer on one side and a thinner one on the other. The wall ends up looking straight, but the weight distribution through the structure is uneven, which can contribute to cracking later.

Uneven Brick Courses

Bricks are meant to be laid in uniform, parallel rows using string lines to keep everything level. When that discipline slips, rows start sagging or climbing. A thick, uniform coat of plaster buries that inconsistency completely, so the problem is invisible until cracks or settling appear years later.

Structural Voids and Poor Binding

To save time and mortar, some bricklayers “perk” bricks, placing a dab of mortar on the ends rather than fully flushing the vertical joints. This leaves air pockets inside the wall that you cannot see once plaster goes on, but they do weaken the structure, allow moisture to travel through the wall, and are a common reason a wall anchor crumbles into empty space when you try to mount a shelf or a television.

The Cost of Fixing It Afterwards

When a wall has these issues, correcting it usually means “building up” or double-skinning the plaster to make the surface look flat, which burns through far more sand and cement than originally budgeted. Thick plaster layers are also more prone to slumping while wet and shrinking as they dry, which is a common cause of cracking before the house is even painted. Our single-skin wall cost breakdown and double-line wall comparison show how quickly plastering costs escalate even under normal conditions, before factoring in a correction job.

Face Brick as a Built-In Quality Check

Choosing face brick for your exterior walls acts as a natural filter for the standard of work on your site. Every joint is on display from the moment it is laid, so the bricklayer has to maintain plumb lines, consistent mortar, and careful handling throughout the job. If you are comparing brick grades for this kind of exposed finish, our guide to FBX vs FBS vs FBA face brick grades explains which one suits your project and budget.

Frequently Asked Questions

How do I check if my wall is out of plumb?

A spirit level or plumb bob run down the face of the wall will show any lean. On a finished plastered wall, a laser level held against the surface can reveal unevenness that is not visible to the eye.

Can a skew wall be fixed without rebuilding it?

Minor deviations can sometimes be corrected with careful plaster building up, but this uses significantly more material and does not fix the underlying structural issue. Significant lean usually requires partial or full rebuilding.

Are structural voids in brickwork common in South Africa?

They occur more often on rushed sites where bricklayers are paid by speed rather than quality. Requesting fully flushed joints and inspecting sample sections before plastering is a reasonable way to check.

Does face brick cost more because of the extra skill required?

Face brick often has a higher labour cost per brick because of the precision involved, but this is frequently offset by removing the plaster, primer, and paint stages entirely. See our full cost comparisons for the numbers.

What should I ask my builder before they start plastering?

Ask to inspect the raw brickwork for plumb, level, and joint consistency before the plaster coat goes on. Once plastered, these issues are far harder to verify.

Get a Quote From Dezyno Bricks

Dezyno Bricks supplies premium clay face brick, semi-face brick, and plaster brick across South Africa from our yard in Springs, Gauteng. Browse our FBS face bricks range or plaster bricks, call us on 061 538 5968, email sales@dezynobricks.co.za, or message us on WhatsApp to get a quote for your next project.