How Much Jointing Compound Do I Need?
Quick Answer
Approximately 0.5 kg per m² of plasterboard
A 30m² room (walls and ceiling) needs ~15 kg of jointing compound plus ~50m of tape
How We Calculated This
- Plasterboard area: 30m²
- Compound per m²: ~0.5 kg (3-coat system)
- Total compound: 30 × 0.5 = 15 kg
- Tape: ~1.5–2m per m² of board = ~50m
Jointing Process (3-Coat System)
- Bedding coat: Apply compound to joint, embed paper tape
- Filling coat: Build up over tape, feather edges to ~150mm wide
- Finishing coat: Thin skim over joint, feather to ~250mm wide. Sand smooth
Types of Compound
- Ready-mixed (tub): Convenient, longer working time, slower drying. ~£8–15 per 5 kg tub
- Setting compound (powder): Sets by chemical reaction (20, 45, 90 min variants). Faster, harder finish
- Finishing compound: Smoother consistency for the final coat
Tape Types
- Paper tape: Standard, strongest bond. Used with compound
- Self-adhesive mesh tape: Easier to apply but less strong. Best with setting compound
- Metal corner tape: For external corners (protects the edge)
Coverage Rates by Brand
- Gyproc Easifill: ~1.3m² per kg (thin coat)
- Knauf Fill & Finish: ~1.5m² per kg
- Siniat GTEC Joint Cement: ~2.0m² per kg
Last updated: April 2026