Concrete Blockwork
This site is for poor nations and for students lacking access to books, libraries and stable Internet connections. If you are in a developed nation, please go to the original site:
From www.brickworks.net.au, accessed Dec 2011
This site has much more to offer and needs your support to continue to offer this information for your benefit.
Click on photos to enlarge. In Firefox, to return, cancel the window of the enlarged photo, or click the tab of this window.
Contents
Gauge
Tools Required.
Laying Method
Starter Bars.
More blockwork.
Finishing Blockwork
Gauge
Nominal block height gauge is 200mm.
Nominal block length gauge is 400mm
Block widths vary: 90mm, 150mm, 140mm and 190mm blocks are available.
Tools Required
Tools required are just standard bricklaying tools.
Setting Out
Similar to standard bricklaying, cutting blocks should be avoided at all times if possible.
Horizontal steel bars are placed every 2 courses, or 400mm centres.
Vertical steel bars are placed every 1 block width also 400mm centres.
Starter Bars
Starter bars stop the blockwork from moving laterally.
The bars are set at 400mm intervals in the concrete footing or slab. They are best set out and drilled into place when the concrete has set.
Positioning the starter bars at the concrete pour stage is very rarely successful as the spacings are usually wrong.
Once the wall has gone off the core of the block is filled with fine concrete and more bars are inserted.



not found
Profiles/Straight edges
Note the profiles/straight edges plumbed at every corner. At the corner the profile sets two walls vertically. This photo shows how each profile must be secured at the top by a diagonal and a cross-piece.
Clamps are preferable to nailing, which tends to move profiles. Clamps allow easy adjustment for fine-tuning of plumb profiles.
Lifting these heavy blocks to head-height and carefully placing on top of others without moving them, requires stamina. Have scaffolding ready, to avoid unnecessary strain.



not found
Steel door frames
The steel door frame has a spreader inserted to stop the jambs from bowing as the blockwork progresses up the jamb.



not found
Efficiency
Note how the site is swept clean of dropped mortar, and buildings materials are grouped so as to keep pathways clear. This avoids materials being in the way and thus slowing builders, and raising labor costs.
In addition, note the warning written large on a doorway. Safety is of utmost importance. You want to avoid injury. The boss wants to avoid losing skilled builders to injury and losing time-off for first-aid treatment.
All injuries, no matter how slight, should be recorded in a specific first-aid diary.



not found
Finishing Blockwork
Finishing blockwork is similar to Finishing Brickwork. The most common mortar finishes in commercial buildings are round jointed, or flush. But blockwork in offices and houses is usually rendered, which requires perpends to be left hollow.