Masonry Works Construction Methodology
Before Masonry Works
1. All precast concrete masonry blockwork will be carried out in accordance with the
specification and Project Quality Plan.
2. Checks Prior to Start of blockwork:
a. Ensure that the area to receive the blockwork is as per the contract
drawings and approved finishing schedule.
b. Check if preceding activities have been inspected and approved.
c. Ensure that blocks are procured from the approved manufacturer(s). Except
where otherwise approved in writing each material shall be obtained from a
single source.
d. Source certificates shall be obtained for all raw materials e.g., sand,
cement, and blocks to show compliance with the contract specification.
3. Handling and Storage of Materials:
a. Blocks shall be delivered to the site palletized and offloaded as near to the
point of use as practicable on a clean hard surface free from contamination
by mud or surface water.
b. Cement shall be stored off the ground, kept dry, and used in order of
delivery.
c. Store metal ties and straps undercover and protect them from damage and
distortion.
4. Preparation of Work, Materials, and Components:
a. When the materials and components are distributed to the work area,
ensure that the structure is not overloaded.
b. Plan for scaffolding material required for block work at heights. Plan for
additional manpower for lifting blocks at heights.
c. Set out anticipating the position of openings etc. in the work above to avoid
unnecessary cutting and adjustment of masonry units leading to incorrect
or uneven bonding.
5. Preparation of Mortar Mixes: (shall be as per specification)
a. Mortar shall be mixed by machine except for small quantities only.
b. Then mixed at the site batch boxes shall be used to ensure correct and
consistent mix proportions.
c. Use mortars (other than retarded mortars) within 2 hours of mixing or as
specified.
During Masonry Works
1. Spread the mortar along 1 corner of the footing.
a. Use a trowel to spread a few slabs of mortar around the corner's base of
the footing.
b. Spread the mortar 1 in (2.5 cm) deep and 8 in (20 cm) wide in the marked
area.
c. Continue to spread the mortar to account for the distance of about 3 to 4
blocks.
2. Center the corner block on the footing.
a. Stand over the footing and gently set the concrete block down, making sure
it’s level and flat.
b. Center the corner block in the footing by measuring around the block and
making sure it’s even.
3. Continue to lay the concrete blocks in a line out from the corner.
a. Start laying blocks from the corner or edge of the wall to work in one
direction.
b. Apply a 1 in (2.5 cm) thick layer of mortar to the sides of each block.
c. Keep laying blocks and applying mortar until it reaches the next corner.
4. Check the alignment of the blocks with a level.
a. Before stacking more concrete blocks on top of the initial foundation, check
if everything is aligned.
b. Use your mason's level by laying it on the first set of blocks.
c. Check both the outside and center sections of the bricks.
5. Apply mortar to the top of the blocks.
a. Use your trowel to spread 1 in (2.5 cm) of mortar over the entire width of the
block.
b. Then, spread the mortar so it covers the length of about 3 blocks in the
direction of laying the bricks.
6. Stack the blocks on top of each other.
a. Lay the block down on top so the edge of the top block aligns with the
halfway mark of the bottom block.
7. Add reinforcement rods for high walls.
a. Place the 1/4" steel reinforcement rods into each opening of the concrete
blocks.
8. Strike the mortar joints.
a. Once the mortar mix has set enough so you can leave a thumbprint in it,
run a concave jointing tool along each joint to remove the excess mortar.
b. Start with the horizontal joints, then move to the vertical joints.
After Masonry Works
1. Let it dry and cure.
2. Cut chases and holes neatly and without damaging the walls as per the following
unless specified otherwise:
a. Chases in blockwork to be less than 75mm.
b. For hollow units maintain a minimum of 15mm thickness between the
bottom of the chase and the void.
c. Do not cut horizontal or raking chases to a depth exceeding one-third the
thickness of the single leaf in walls or leaves contracted of solid units.
d. Holes shall not exceed 300mm x 300mm unless specified otherwise.
e. Do not cut chases back-to-back exceeding the dimensional restrictions in
a, b, and c. Offset such chases in line by a distance at least equal to the
wall thickness.
f. It is preferable to use approved cutting tools, particularly when it is
necessary to avoid heavy impact and vibration. The number and position of
chases shall be strictly in accordance with the specification since
unauthorized chasing might adversely affect one or more of the functional
requirements of the walls e.g., its loadbearing capacity.