diff --git a/printed/butt_box.scad b/printed/butt_box.scad
index 6880fa9..703e704 100644
--- a/printed/butt_box.scad
+++ b/printed/butt_box.scad
@@ -50,6 +50,10 @@ function bbox_name(type)       = type[8] ? type[8] : "bbox"; //! Optional name i
 function bbox_skip_blocks(type)= type[9] ? type[9] : [];  //! List of fixing blocks to skip, used to allow a hinged panel for example
 function star_washers(type)    = type[10] ? type[10] : is_undef(type[10]); //! Set to false to remove star washers.
 
+function bbox_volume(type) = bbox_width(type) * bbox_depth(type) * bbox_height(type) / 1000000; //! Internal volume in litres
+function bbox_area(type) = let(w =  bbox_width(type), d = bbox_depth(type), h = bbox_height(type)) //! Internal surdface area in m^2
+    2 * (w * d + w * h + d * h) / 1000000;
+
 module bbox_shelf_blank(type) { //! 2D template for a shelf
     dxf(str(bbox_name(type), "_shelf"));
 
@@ -205,7 +209,7 @@ module _bbox_assembly(type, top = true, base = true, left = true, right = true,
     width = bbox_width(type);
     depth = bbox_depth(type);
     height = bbox_height(type);
-    echo("Box:", width, depth, height);
+    echo("Box:", width, depth, height, volume = bbox_volume(type), area = bbox_area(type));
 
     t = sheet_thickness(bbox_sheets(type));
     bt = sheet_thickness(bbox_base_sheet(type));
diff --git a/readme.md b/readme.md
index 9bb787b..3a766b0 100644
--- a/readme.md
+++ b/readme.md
@@ -3243,6 +3243,12 @@ Uses [fixing blocks](#fixing_block) and [corner blocks](#corner_block).
 | ```bbox_width(type)``` | Internal width |
 | ```star_washers(type)``` | Set to false to remove star washers. |
 
+### Functions
+| Function | Description |
+|:--- |:--- |
+| ```bbox_area(type)``` | Internal surdface area in m^2 |
+| ```bbox_volume(type)``` | Internal volume in litres |
+
 ### Modules
 | Module | Description |
 |:--- |:--- |
@@ -3253,6 +3259,7 @@ Uses [fixing blocks](#fixing_block) and [corner blocks](#corner_block).
 | ```bbox_base_blank(type)``` | 2D template for the base |
 | ```bbox_front(type)``` | Default front, can be overridden to customise |
 | ```bbox_front_blank(type, sheet = false)``` | 2D template for the front |
+| ```bbox_front_blank(type, sheet = false, width = 0)``` | 2D template for the front |
 | ```bbox_left(type)``` | Default left side, can be overridden to customise |
 | ```bbox_left_blank(type, sheet = false)``` | 2D template for the left side |
 | ```bbox_right(type)``` | Default right side, can be overridden to customise |