Fill and sand a wall
Save £50–100 in 45 mins — no decorator needed
Most people hire a decorator for this. You probably don't need to.
Last updated: March 2025
Only basic tools needed — most homes already have them.
Before you start
Filling and sanding is the most important prep work before painting. Skipping it shows through even two coats of paint.
Most holes and cracks in a wall are caused by nails, screws, minor impacts, or normal shrinkage. All of them can be fixed with the same basic technique.
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Tools & materials
- ✓Filling knife— a 4-inch flexible blade is ideal — you may already have one
- ✓Small bowl of water— to wet the filler before applying
- !Ready-mixed filler— buy — Polyfilla or own-brand equivalent from any hardware shop
- !Sandpaper 120-grit and 240-grit— buy — coarse to shape, fine to finish
- !Primer or mist coat— buy — needed over bare filler before painting
Want everything in one go?
Prices shown on retailer sites. Always check current pricing before purchasing.
Clean out the hole
Remove any loose plaster, dust, or old paint from inside the hole with a screwdriver tip or brush. The filler needs to bond with solid material.
Most people get this done in under 5 minutes.
Where beginners go wrong
Painting straight over filler without priming — filler is porous and shows as a dull patch through paint.
Not cleaning out the hole first — filler applied over loose material falls out within days.
Underfilling and trying to sand it flat — it is better to slightly overfill and sand back.
Stop and call a decorator if...
Cracks that keep coming back — this indicates structural movement
Cracks wider than 5mm or at window and door corners — may need specialist attention
Damp or discolouration around the crack — fix the source of moisture first
Cost breakdown
Recommended starter kit
Five tools that cover most home repairs.
- →Adjustable spannerAmazon·Screwfix
- →Screwdriver setAmazon·Screwfix
- →PTFE tapeAmazon·Screwfix
- →Spirit levelAmazon·Screwfix
- →Tape measureAmazon·Screwfix
Want everything in one go? Get it on Amazon
What you just learned
You now know how to prepare walls to a paint-ready standard. Filling and sanding is the skill that separates a professional-looking paint job from an amateur one.
Most people would pay a tradesperson for this.
⚠️ Watch out if you rent
Filling small nail holes when you leave is expected and helps protect your deposit. For larger holes, check your tenancy agreement — significant damage beyond fair wear and tear may be chargeable.