GreenLock V12 Block

Planning

• Measure the height and length of the proposed wall and multiply these two numbers together to calculate the square meter surface area. Multiply this number by 12 to obtain the number of blocks required for the wall. 
• Retaining walls must comply with local building regulations.
• A rule of thumb is, where the wall is less than 1,2m built to a batter of 70° (from horizontal) and
  where soil and drainage conditions are good and well compacted, there should be no need for an
  engineer. Where however, the height of the wall exceeds 1,2m, or if problem soils (clay) or a high
  water table exists, or where a structure is to be erected on top of the retained fill close to the wall, or
  even load bearing walls, then the services of an engineer or competent person are required. In such
  cases, the local authorities should insist on a design and stability certificate from the engineer

Typical Installation

• Measure the wall layout and mark the course using string and stakes.
• Dig a trench 400mm deep, 600mm wide and create either compacted gravel or a concrete base 200mm deep. (Gravel foundations are usually sufficient for walls less than one (1) meter in height.) It is imperative that the foundation is level in all directions.
• Place the first row of blocks on the foundation ensuring that the concave and convex interlocking ends of the blocks mesh as closely as possible. The blocks must be placed level in all direction on the foundation. If need be and to level the first block row perfectly, one can embed the first block row in a mortar bed.
• Each marker (inset dimple) on the block represents a 10º (ten degree) change in angle. For a twenty degree curve, line up the second marker with the main marker. A maximum turn of 105º can be achieved. The seven markers on the large circumference of the block represent an angle of 45 ° between each marker.

What is the “OFF SET”

One measures the OFF SET at the beginning of each block row. It is the dimension measured from the edge of the first block of the first row to the edge of first block of the second block row laid and so on. For the visual effect of a retaining wall it is important to note that the distance / dimension of the OFF SET at the beginning of each block row should always be the same. Even if curves, circles or soft angles are integrated into a wall, this rule applies. For instance if one chooses to lay the first block of the second
row of blocks exactly halfway over the joint of the first block row, then each subsequent row should be laid the same way. The GreenLock 12 series is 380mm long the OFF SET dimension would then be 180mm.

It is not important what the OFF SET dimension is, as long as it always the same dimension with each row laid. If one follows this advise the finished wall will look stunning, aesthetically pleasing and important for the eye, with evenly fluted joints. If one does not follow this rule, the wall will not be weaker but it will visually look untidy and create a “dizzy” look.

Important Note:

If a sharp corner, like 45 or 90 degrees corner is integrated into the wall this rule does not apply. For sharp corners and after the first block row has been placed and laid including the corner, the second row of blocks should start with the corner block placed exactly over the bottom corner block using the chosen Set Back dimension. The next blocks are then laid in both directions away from the corner block. The joints between the blocks of each block row will automatically form an evenly distributed fluted pattern over the
whole length and height of the finished wall.

The 45° marker on the back block lines up with the centre marker on the front block, means that there is a 45 ° angle between the blocks.

The 45° marker on the back block lines up with the 10° marker on the front block giving an angle of 35° between the blocks.
The 45° marker on the back block lines up with the 10° marker on the front block giving an angle of 35° between the blocks.