Plaster Cracks Around Windows _verified_ Jun 2026

| Design Element | Specification | | --- | --- | | Frame anchor type | Slotted or adjustable (allow ±3 mm movement) | | Plaster type near windows | Lime-cement-sand (1:1:6) with 0.5 kg/m³ polypropylene fibers | | Corner reinforcement | Perforated stainless steel L-angle, overlapped 100 mm at corners | | Window-to-plaster joint | 5–8 mm gap with backer rod + sealant, never butt joint | | Lintel bearing | Minimum 150 mm bearing each side; cambered to prevent deflection | | Sill support | Continuous steel angle or full-depth sub-sill blocking |

Once the compound is bone dry, sand it smooth with fine-grit sandpaper. Feather the edges so the patch blends into the existing wall. Wipe away dust with a damp cloth, prime the area, and paint. plaster cracks around windows

How do you know if you should grab a putty knife or call an engineer? | Design Element | Specification | | ---