Undercoat gypsum bag calculator: area and thickness
Our undercoat benchmark is one 33 kg bag per 1.3 m² at 2 cm. Enter the actual wall and ceiling area, thickness and bag weight. Confirm the final quantity with your plasterer, allowing for surface unevenness and application.
Calculate bags for your project
Enter the wall and ceiling area to be plastered, average undercoat thickness and bag size. Your estimate updates immediately.
Sales benchmark: one 33 kg bag for 1.3 m² at 2 cm. Thickness and bag size scale proportionally.
Enter a positive area and thickness and select a bag size.
This is an undercoat estimate, rounded up to whole bags with no additional waste allowance. Surface unevenness and application affect consumption; confirm with your plasterer. Plastering area differs from floor area.
Choose a product and view prices →Your questions, answered
How far does a bag of gypsum-soil plaster go?
Our undercoat benchmark is one 33 kg bag per 1.3 m² at 2 cm. Enter the actual wall and ceiling area, thickness and bag weight. Confirm the final quantity with your plasterer, allowing for surface unevenness and application.
How many bags do I need for 100 m²?
At an average 2 cm, 100 m² of surface needs about 2,538.5 kg, rounded up to 77 bags of 33 kg. This is wall/ceiling area, not floor area; confirm uneven surfaces with your plasterer.