Two different jobs
Before a repaint, Indian walls often show both roughness and cracks. Homeowners reach for wall putty hoping one product will fix everything. It usually will not.
- Wall putty smooths micro-pores and minor undulations so the finish looks even.
- Crack filler (a flexible acrylic or cementitious repair compound made for cracks) rebuilds a damaged line or gap so the crack does not telegraph through the paint.
Using putty as a “cheap crack filler” on deep or live cracks is one of the most common reasons lines reappear after the first season of heat and rain.
Quick comparison
| Wall putty | Crack filler | |
|---|---|---|
| Best for | Fine levelling, pinholes, slight waves | Visible cracks and gaps that need repair |
| Typical thickness | Thin skim coats | Fills the opened crack depth as directed on the tin |
| Flexibility | Levelling compound—not designed as a movement joint | Choose a filler suited to minor movement where appropriate |
| When to use | After cracks are repaired (or alone if no cracks) | Before full putty on cracked walls |
| Cannot replace | Primer or topcoat | Structural repair or waterproofing |
This guide keeps crack filler generic—confirm the exact repair product with your dealer. Focus on sequence into MRF primers and finishes once repairs have cured.
Crack types in homeowner language
Hairline / shrinkage cracks
Fine lines from plaster drying or temperature movement. Often cosmetic if the wall is dry and stable. Still open them slightly, clean, and fill with a suitable crack filler rather than smearing putty over the top.
Wider plaster cracks
You can fit a fingernail or more. Open, clean out dust, fill in layers if needed, cure, sand flush, then putty the surrounding area for a uniform face.
Damp-related cracks and stains
Cracks with dark edges, soft plaster, or white salts point to moisture. Painting over them without fixing seepage (bathroom leaks, external seepage, roof damp) invites a repeat. See also bathroom walls and exterior climate guidance for seepage façades.
Structural / settlement cracks
Zigzag cracks across beams and columns, cracks that keep widening, or cracks tied to doors that suddenly stick. Stop and call a structural professional. Decorative filler and emulsion will not make an unsafe wall safe.
Decision tree
- Only slight roughness, no visible cracks → putty as needed → primer → paint
- Hairline or plaster cracks, wall dry and stable → crack filler first → putty → primer → paint
- Cracks with damp → fix moisture → dry → filler → putty → primer → paint
- Widening / zigzag / structural signs → engineer first; do not rely on paint
Recommended order before painting
- Diagnose the cause — movement, shrinkage, or water. Fix active leaks first.
- Open and clean the crack — remove loose material; dust-free surfaces bond better.
- Apply crack filler — follow the product’s depth limits and cure time. Deep cracks may need more than one pass.
- Cure fully — do not rush sanding or putty onto soft filler.
- Sand flush — feather edges so the repair does not show as a ridge.
- Wall putty — skim the area (or full wall if specified) for a uniform plane; sand.
- Primer — use the primer matched to your finish (putty vs primer order).
- Topcoat — two coats of the chosen MRF interior or exterior finish as the room requires.
On new plaster, also respect curing time—MRF prep notes require freshly plastered surfaces to cure, with coating after a minimum of 30 days. See how long after plaster.
Mistakes that bring cracks back
- Putty-only on deep cracks — putty shrinks and the line returns.
- Painting over active damp — filler and paint fail together.
- Skipping primer after repairs — uneven absorption highlights every patch.
- Ignoring exterior seepage — interior filler cannot stop water driving from outside.
- Expecting paint to stop structural movement — it will not.
After repair — MRF painting system
Once fillers and putty have cured and the wall is clean and dry:
- Primers: Altura 2-in-1 Wall Primer or AquaFresh PU Wall Primer as suited to your topcoat. Browse the primer hub.
- Putty: MRF VILASA Wall Putty is named on Altura application notes for levelling undulations—confirm coats and use on the product sheet. Putty is for smoothness after cracks are filled, not a substitute for filler on open cracks.
- Topcoats: AquaFresh, Altura, or Visa lines according to interior/exterior needs—only after the repair stack is sound.
Match primer and finish from the same system where possible, and follow recoat intervals on the tin.
Exterior vs interior (high level)
Interior cracks are often shrinkage or minor movement. Exterior cracks more often tie to sun, rain, and seepage—so waterproofing and façade drainage may matter before any filler. Use exterior-rated systems outdoors; do not assume an interior emulsion will protect a cracked exterior wall.
Related guides
- Putty vs primer: correct order
- How long after plaster before painting
- Best exterior paint for Indian climate
- Best paint for bathroom walls
Next step
If cracks keep returning, fix the moisture or movement source first. When repairs have cured, ask an MRF Paints dealer for the right primer and finish for the room—not another coat of putty over an open crack.
