Typical renovation order
- Insulation in open walls and ceilings.
- Drywall: sheets, tape, compound and screws.
- Paint: walls, ceiling and primer for new drywall.
- Flooring or Tile.
- Baseboard and trim to cover expansion gaps.
Start with the square footage calculator if your rooms aren't simple rectangles. You can add each result to your project list to build one shopping list for the whole room.
Measuring a room once for everything
Write down the length, width and ceiling height of each room, plus the size and number of doors and windows. Those few measurements feed every interior calculator here: wall area for drywall and paint, floor area for flooring and tile, perimeter for baseboard.
Waste allowances differ by material
| Material | Typical allowance |
|---|---|
| Drywall | About 10% |
| Flooring, straight lay | 5–10% (check the manufacturer) |
| Tile, straight / diagonal / herringbone | ~10% / ~15% / ~20%, plus a spare box |
| Baseboard / crown | 10% / 15% |
These are rules of thumb. Each calculator page explains when to go higher.