Pose des Corniches de Plafond : Guide Pas à Pas

Manuel de pose pas à pas pour réussir les angles rentrants et saillants sans jours disgracieux, encollage parfait et peinture sans traces.

La pose de corniches de plafond en polyuréthane transforme l'atmosphère d'une pièce en assurant une liaison parfaite entre le mur et le plafond.

Étape 1 : Traçage de la Ligne Guide Murale

Step 1: Surface Preparation and Layout Marking — Clean dust, grease, and loose paint from the installation path. Measure down from the ceiling using the profile height dimension and snap a chalk line along the perimeter. Estimated Duration: 20-30 minutes per room. Common Mistake: Installing over dusty or damp substrates without checking if the surface is fully dry and sound.
Step 2: Dry-Fit Measurement and 45-Degree Miter Cutting — Measure corner-to-corner distances and cut 45-degree miter angles on a compound saw with the profile inverted against the fence. Test fit joint ends in place without adhesive. Estimated Duration: 30-45 minutes. Common Mistake: Failing to measure actual corner angles with a protractor, assuming all room corners are perfectly 90 degrees.
Step 3: Polyurethane Adhesive Bead Application — Apply continuous 6 mm beads of polyurethane assembly adhesive along the top and bottom mounting flanges on the reverse side of the profile. Estimated Duration: 15-20 minutes. Common Mistake: Using standard silicone sealant instead of dedicated polyurethane adhesive, which leads to joint failure.
Step 4: Profile Mounting and Mechanical Screw Securing — Press the profile firmly into the wall-ceiling corner along the reference line. Drive countersunk screws through the profile into wall anchors spaced every 40-50 cm. Estimated Duration: 30-60 minutes. Common Mistake: Omitting mandatory mechanical screw fixings and relying solely on adhesive to support profile weight.
Step 5: Joint Putty Application and grain 180-220 Sanding — Fill screw holes and profile butt joints with joint filler. Allow full drying, then sand smooth using grain 180-220 sandpaper. Estimated Duration: 45 minutes (excluding putty drying time). Common Mistake: Sanding with coarse grit under 180, which gouges the factory-primed polyurethane coating.
Step 6: Localized Priming and Two-Coat Paint Finishing — Spot-prime sanded joint areas. Apply two uniform coats of paint over the entire profile length, ensuring UV-resistant paint is selected for exterior projects. Estimated Duration: 1-2 hours (plus coat drying interval). Common Mistake: Applying standard interior paint on exterior installations subject to UV radiation and thermal shifts between -100 °C / +80 °C.

Étape 2 : Découpe en Boîte à Onglets Inversée

Placez la corniche en appui inversé dans la boîte à onglets et sciez à 45° en appliquant une marge de coupe de 10%.

Étape 3 : Double Encollage et Pose Mur-Plafond

Déposez un cordon de colle structurelle colle de montage à base de PU (séchage en environ une heure) sur les deux talons de contact et pressez fermement sur le tracé.

Étape 4 : Masticage des Angles, Ponçage et Peinture

Comblez les joints au mastic acrylique souple, poncez au grain fin grain 180-220 et peignez sur l'apprêt primaire acrylique blanc monocomposant sous -100 °C / +80 °C. Imperméable (inférieure à 1 %). Devis valables 7 jours, livraison départ usine départ usine.