Frequently Asked Questions


Installation of Rib & Block System

  1. Space ribs out evenly on top of slab on 2 layers of DPC (damp course) with a block in between the ribs for accurate spacing.
  2. Install the support shuttering and props to support slab underneath crossribs / stiffner ribs @ equal centers of 1.5m (leveled).
  3. Place the balance of the blocks as per engineer’s drawings. No blocks to be placed on top of crossribs.
  4. Place the Y-10 steelbar reinforcing on top of crossrib shuttering.
  5. Install all beams-, skylights- and cantilever reinforcing as per engineer’s specs.
  6. Plumber and electrician to install services including downlighter boxes, etc.
  7. Ref100 Mesh to be placed on top of slab and services material. No electrical down pipes to be sticking through the Mesh.
  8. Polystyrene to be placed between the concrete slab and the outside brick walls.
  9. Remove all the rubble from the slab and wash any excess material from the slab.
  10. The appointed engineer has to inspect the slab before casting can commence.
  11. Concrete casting to be done – readymix @ 25 mpa to 30 mpa pumpmix (as per engineer’s specs).
  12. Reinforced beams MUST at all times be casted with a poker vibrator and a needle!!! The concrete needs to grip properly around the reinforcing steel.
  13. Small slabs can be casted by making use of a concrete mixer and by using an approved recipe available at our office.
  14. Wet the slab every day for at least 5 days after casting for proper curing.
  15. Wall on wall brickwork can proceed within 24 hours after casting. All other brickwork on the slab has to be done after the props have been removed.
  16. Props to be removed after 14 days.
  17. Engineer’s Completion Certificate will be issued after the removal of props and shuttering.
  18. Plaster only once props have been removed as the slab has settled.


  1. Final quotations can only be given once the final measurements were done on site.
  2. Final reinforcing steel quotations can only be given once the engineer’s have been consulted.
  3. Concrete pillars to be casted with the correct reinforcing (engineer’s specifications) with a proper footing!
  4. Lintels are often used to build staircases. These staircases require built walls on both sides of the staircase, so that the lintels and brickwork can be placed on these walls for support.
  5. If you need your plans stamped by our independent structural engineer together with a letter of appointment from him for your City Council submission, we will assist you with the process. The full engineer’s fee is payable before any plans will be submitted at the engineer’s office.


Free consultations and technical advice are rendered at our office by qualified and experienced personnel.
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