diff --git a/htdocs/product/class/product.class.php b/htdocs/product/class/product.class.php
index 56b9fc527a6..695ab573805 100644
--- a/htdocs/product/class/product.class.php
+++ b/htdocs/product/class/product.class.php
@@ -640,6 +640,20 @@ class Product extends CommonObject
 		$this->width_units = trim($this->width_units);
 		$this->height = price2num($this->height);
 		$this->height_units = trim($this->height_units);
+		// Automated compute surface and volume if not filled
+		if (empty($this->surface) && !empty($this->length) && !empty($this->width) 
+		    && $this->length_units == $this->with_units  
+		) {
+			$this->surface = $this->length * $this->width;
+			$this->surface_units =  $this->width_units;
+			if (empty($this->volume) && !empty($this->height)
+			    && $this->length_units == $this->height_units  
+		   	) {
+				$this->volume =  $this->surface * $this->height;
+				$this->volume_units = $this->height_units;
+			}
+		}
+		
 		$this->surface = price2num($this->surface);
 		$this->surface_units = trim($this->surface_units);
 		$this->volume = price2num($this->volume);