Calculatrice de Corniche

Dernière mise à jour: 2026-06-23

Utilisez le Calculatrice de Corniche pour obtenir des résultats précis. Saisissez vos valeurs ci-dessous.
Données
Résultat
Entrez les valeurs et appuyez sur Calculer
Common Sizes — Click to Fill
Longueur de la pièce (m) Largeur de la pièce (m) Longueur de chaque pièce (m)
Small door 2.5 m 2 m 2.4 m
Standard door 3.75 m 3 m 2.4 m
Large door 5 m 4 m 2.4 m
Window 7.5 m 6 m 2.4 m
Bay window 10 m 8 m 2.4 m
Outils associés
Calculatrice de Plinthe Calculatrice de Terrasse Calculatrice de Palissade Calculateur Fenêtres Aluminium/PVC

Qu'est-ce que le Crown Molding Calculator?

Crown molding runs along the ceiling perimeter of a room, and ordering the right linear metres is critical — molding is sold in fixed lengths (typically 2.4 m or 3.6 m) and joins are visible if you use short off-cuts. This calculator computes the room perimeter, adds 10% for angled cuts and waste, and tells you how many lengths to buy.

You may also find the Baseboard Calculator, Decking Calculator, and Fence Picket Calculator useful.

Qui utilise cette calculatrice?

This tool is used by homeowners installing crown molding, finish carpenters quoting trim jobs, and interior designers specifying millwork.

Comment utiliser the Crown Molding Calculator

  1. Saisissez votre Room length.
  2. Saisissez votre Room width.
  3. Saisissez votre Corner type.
  4. Saisissez votre Molding piece length.
  5. Cliquez sur Calculer pour voir vos résultats instantanément.

Formule

The calculator uses the following formula:

Perimeter = 2 × (length + width); Linear metres needed = perimeter × 1.1; Pieces = ceil(linear_m ÷ molding_length)

Exemple de calcul

A 5 m × 4 m room with 90-degree corners requires 18 m of molding perimeter. Adding 10% waste gives 19.8 m — so buy 9 lengths of 2.4 m molding (21.6 m total).

Calcul étape par étape

  1. Room perimeter: 2 × (5 + 4) = 18 m
  2. Add 10% for mitre cuts and waste: 18 × 1.1 = 19.8 m
  3. Pieces of 2.4 m: ceil(19.8 ÷ 2.4) = 9 pieces

Erreurs courantes à éviter

  • Not adding extra for mitre cuts — each inside corner wastes ~5 cm per piece
  • Forgetting to measure the height at which crown contacts the wall and ceiling
  • Ordering standard lengths without checking if longer pieces reduce waste
Pro Tip: Use a compound mitre saw for crown molding corners — the dual-angle cuts are difficult to do accurately with a standard mitre box. For large rooms, use longer molding lengths to minimise joins.

Questions fréquentes

How do I cut crown molding corners?
Crown molding corners require compound mitre cuts — typically 45° mitre and 33.9° bevel for 90-degree inside/outside corners. A dedicated crown molding mitre setting on your saw makes this easier. Test cuts on scrap before cutting good stock.

What is the waste allowance for crown molding?
10% is standard for rooms with 90-degree corners. Add 15–20% if the room has many corners or bay windows, since each corner requires angled cuts that waste material.

Should crown molding be nailed to studs or the top plate?
Crown molding should be nailed at 45 degrees into both the ceiling and wall — hitting studs and ceiling joists where possible. Use a stud finder first. Finish nails (50–65 mm) with a nail gun give the cleanest result.

How do I fill gaps between crown molding and the wall?
Use paintable latex caulk, not silicone. Apply a thin bead along the top and bottom edges, smooth with a damp finger, and paint after it dries. Small gaps (< 3 mm) are expected and easily caulked.

Can crown molding be installed on vaulted ceilings?
Yes, but it requires raking crown molding that runs at the slope of the ceiling, not horizontal. The calculations are more complex. For dramatic vaults, consider cove molding which is more forgiving to install.

Écrit et révisé par l'équipe éditoriale de CalcToWork. Dernière mise à jour : 2026-06-23.

calcto.work — Calculated on 2026-06-23