The plans shown below are for six basic designs, which - because of the simplicity and modularity of the VN concept - can be readily extended and customised, provided the following conditions are respected:

  All load-bearing walls are 60 cm wide, and gable walls 40 cm wide. A vault can be any length, but its width cannot exceed 3, 25 m.

 Openings can be made in load-bearing walls every 80 cm at the most. Such openings can be complete (for windows) or partial (for shelving, niches, cupboards). Note that the numbers of windows shown on the plans below are the maximum number technically possible: most VN clients fit fewer windows.

These strictly defined dimensions guarantee the stability of the vault.

The total average cost per square metre of a VN building 12 000 Francs CFA, i.e. 39 000 Francs CFA for each linear metre of vault constructed.

External Kitchen model

1 short vault (roof area equivalent to13 metal roofing sheets)

• Ext length : 5,3 m
• Ext width : 4,45 m
• 1 wide gable wall opening to outside
• Up to 8 windows possible

Estimate of time and materials for basic structure:

• Materials :
  — 10 barrows of rocks (laterite)
  — 1220 large bricks (c. 38 cm long X 18 cm wide X 18 cm high)
  — 20 barrows of good quality earth for the small bricks and mortar for the vault
  — 43 barrels of water

• Labour :
  — 15 days for 1 VN builder
  — 15 days for 1 apprentice
  — 12 days each for 3 labourers

Living room - Bedroom model

1 vault (equivalent roof area to 20 metal roofing sheets)

• Ext length : 8,3 m
• Ext width : 4,45 m
• 1 bedroom (3m long), 1 living room (4.3m long)
• 1 ext door, 1 int door, and up to 13 windows

Estimate of time and materials for basic structure:

• Materials:
  — 14 barrows of rocks (laterite)
  — 1920 large bricks (c. 38 cm long X 18 cm wide X 18 cm high)
  — 31 barrows of good quality earth for the small bricks and mortar for the vault
  — 67 barrels of water

• Labour :
  — 24 days for 1 VN builder
  — 24 days for 1 apprentice
  — 19 days each for 3 labourers

’Pistol’ model

2 vaults : 1 long and 1 short, at right angles (equivalent roof area to 36 metal roofing sheets)

• 1 vault ext lenghth : 9.8 m
• 1 vault ext length : 5.3 m
• Ext width of each vault : 8.3 m
• 1 bedroom (4.5m long), 1 salon (5.6 m long) and 1 kitchen (3.2 m long)
• 1 ext door, 2 int doors and up to 19 windows

Estimate of time and materials for basic structure:

• Materials:
  — 26 barrows of rocks (laterite)
  — 3265 large bricks (c. 38 cm long X 18 cm wide X 18 cm high)
  — 53 barrows of good quality earth for the small bricks and mortar for the vault
  — 114 barrels of water

• Labour :
  — 20 days each for 2 VN builders
  — 20 days each for 2 apprentices
  — 20 days each for 5 labourers

Standard model

2 vaults (equivalent roof area to 43 metal roofing sheets)

• Ext length : 9.8 m
• Ext width : 8.3 m
• 2 bedrooms (3.2 m long and 4.5 m long), 1 shower, 1 salon (5.6 m long) and 1 kitchen (3.2 m long)
• 1 ext door, 4 int doors and up to 19 windows

Estimate of time and materials for basic structure:

• Materials:
  — 30 barrows of rocks (laterite)
  — 4222 large bricks (c. 38 cm long X 18 cm wide X 18 cm high)
  — 69 barrows of good quality earth for the small bricks and mortar for the vault
  — 147 barrels of water

• Labour :
  — 25.5 days each for 2 VN builders
  — 25.5 days each for 2 apprentices
  — 25.5 days each for 5 labourers

Standard model + 1 bedroomet and 1 véranda

3 vaults (equivalent roof area to 63 metal roofing sheets)

• Ext length: 12,15 m
• Ext width : 9,8 m
• 3 bedrooms (3,2 m, 4,1 m et 4,5 m long), 1 shower, 1 salon (5,6 m long), 1 kitchen (3,2 m long) and 1 véranda (4,7 m long)
• 1 ext door, 7 int doors portes and up to 23 windows

  

Estimate of time and materials for basic structure:

• Materials:
  — 43 barrows of rocks (laterite)
  — 6165 large bricks (c. 38 cm long X 18 cm wide X 18 cm high)
  — 100 barrows of good quality earth for the small bricks and mortar for the vault
  — 215 barrels of water

• Labour :
  — 37 days each for 2 VN builders
  — 37 days each for 2 apprentices
  — 37 days each for 5 labourers

Basic Two-storey model

4 vaults : 3 on ground floor, 1 on first floor (equivalent roof area to 92 metal roofing sheets)

• Ext length : 12,15 m
• Ext width : 9,8 m
• 5 bedrooms (3,2 m, 4,5 m, 4,4 m, 4,4 m, and 3,2 m long), 2 salons (4,4 m long), 1 shower, and 1 kitchen (3,2 m long)
• 1 ext door, 7 int doors and up to 37 windows (23 on ground floor + 14 on first floor)

  

Estimate of time and materials for basic structure:

• Materials:
  — 63 barrows of rocks (laterite)
  — 8960 large bricks (c. 38 cm long X 18 cm wide X 18 cm high)
  — 146 barrows of good quality earth for the small bricks and mortar for the vault
  — 313 barrels of water

• Labour :
  — 54 days each for 2 VN builders
  — 54 days each for 2 apprentices
  — 54 days each for 5 labourers