Block walls and plaster: straight, staggered and cured
New walls and plaster are covered by paint within weeks. Cracks that appear later usually started with rushed curing or poor joints.
- 1.5 cmmaximum plaster per coat for one common ready-mixManufacturer
- 3+ dayskeeping plaster damp, out of sun and windManufacturer
- ¼ blockminimum stagger of vertical jointsGood practice
- Lintelover every door and window openingGood practice
Good blockwork is laid on full mortar beds with vertical joints staggered course by course and a lintel over every opening. Plaster goes on a dampened wall, at the thickness per coat the product allows (one common ready-mix: up to 1.5 cm per coat), with corner beads, and is kept damp for days after, out of sun and wind. In Dubai heat, rushed curing is the main cause of cracks.
Why check before it is covered. Cracked plaster can be patched, but patches show through paint; a crooked or badly bonded wall has to come down.
The checklist
0 of 14 checked · 0 issuesEach check shows its basis: Manufacturer Published standard Good practice. Hold points, in coral, are the moments to see the work before it is covered.
Before any wall goes up
At design stage- Community approval, and a permit where needed, is in place for new or moved walls Moving walls is a modification in most master communities. Use the approvals finder. Good practice
- No load-bearing wall is removed without an engineer’s design and a permit Structural changes need a consultant. See structural changes. Good practice
- Wall lines marked on the floor as the drawing shows, and agreed Moving a wall after it is built means rebuilding it. Good practice
Blockwork
While walls go up- Each block on a full bed of mortar, joints about 10 mm8–12 mm Thin or patchy joints make weak walls. Good practice
- Vertical joints staggered by at least a quarter block, course by course¼ block Joints in a line make a crack line. Good practice
- Walls plumb and straight, checked with a level as they rise A wall out of plumb shows at every corner and doorframe. Good practice
- A lintel over every door and window opening Without one, the blocks above crack or sag. Good practice
- Mortar used fresh, within about an hour and a half, never re-watered Re-watered mortar is weak. Good practice
Plaster
While plastering- The wall is dampened a few hours before plastering A dry wall sucks water out of the plaster and it cracks. Manufacturer[1]
- No coat thicker than the product allows≤ 1.5 cm For one common ready-mix plaster. Thicker coats slump and crack. Manufacturer[1]
- Corner beads on every exposed corner, plaster level and straight Beads give sharp, straight corners that do not chip. Good practice
Curing
For days after plastering- Plaster sprayed with water several times a day for at least 3 days3+ days One common ready-mix: 3 to 4 times daily for at least three days. Many Dubai contractors cure for 7. Manufacturer[1]
- Fresh plaster protected from direct sun and wind Fast drying is the main cause of plaster cracks in Dubai. Manufacturer[1]
- No cracks, hollow-sounding patches or loose areas before painting Tap the wall. Hollow plaster comes away later. Good practice
All 14 checks, including the hold point. Tick them on site, add notes and photos, and download a PDF to send your contractor. Free with a SoukLocal account.
Sign in freeQuestions to ask your contractor
- Do we have the community approval for the new walls?
- Will there be a lintel over every opening?
- Which plaster, and how will you cure it in this heat?
- How long will you wait before painting?
Questions
Why does new plaster crack in Dubai?
Mostly because it dries too fast: a dry wall, coats too thick, or no curing in sun and wind. Plaster makers say to dampen the wall first, keep each coat within the stated thickness and keep the plaster damp for days afterwards.
How long should plaster be cured?
As the product says. One common ready-mix plaster needs spraying 3 to 4 times a day for at least three days, protected from sun and wind. Many Dubai contractors cure for 7 days.
Do I need approval to build a new wall in my villa?
Often yes. In most master communities a new or moved wall is a modification that needs the developer’s NOC, and some need a permit. Load-bearing walls always need an engineer.
Sources
Written from the working method statements of a Dubai design-and-build contractor, then checked against manufacturer data sheets and published guidance. Each check says which. Manufacturer figures are examples from one product or system: follow the data sheet for the product used on your job. This page helps you ask the right questions; it is not a certificate that work is sound.
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