Home Improvement
Moulding Calculator
Enter perimeter, opening widths, waste and stick length to see linear metres and sticks to buy.
How much moulding do I need?
Moulding and trim are sold in sticks of fixed length, so the job is linear metres first: room perimeter (or measured runs) minus openings you will not cover, then waste for miters and mistakes, then divide by stick length and round up. Crown, chair rail and picture rail follow the same take-off idea even when profiles differ. External returns and complex bay windows need extra beyond a flat waste percent. Skirting uses nearly identical maths — see skirting board — and paint quantities for the same walls sit in the paint calculator.
Worked example
Perimeter 16 m − 2.4 m openings = 13.6 m; +10% ≈ 15.0 m; 2.4 m sticks → 7 sticks.
Limits and assumptions
Straight runs. Does not invent lengths for every miter scrap — raise waste on ornate rooms.
Frequently asked questions
Perimeter or individual walls?
Either — sum the runs where moulding will sit. Do not count openings twice.
What waste % is sensible?
Simple rectangles often 5–10%; many corners or short offcuts may need 15%+.
Is moulding the same as skirting?
Skirting is a common floor-level moulding; this page is generic for any linear trim profile.
Paint before or after install?
Often prime lengths before fixing; final coat after — quantities are separate from stick counts.