Quality Control

HAZ Stone quality control plan:

The objectives of the HAZ Marble Quality plan is to establish and set out those procedures which need to be adopted and operated in order to ensure that all work carried out at the project:

1) Accords fully with the design intent of the project architects.
2) Complies in full with the Contract Specifications.
3) Performs completely in accordance with the Contract performance specifications.
4) Follows fully the requirements of all standards laid down in the contract.
5) Provides the Client with all the necessary information, calculations, samples and drawings to enable the Client or any future Owner to identify all work has been carried out in accordance with the Contract documents.

The Quality Control Plan shall be prepared under three main following headings:

Pre-Installation phase,
Installation phase,

Pre-Installation phase:

The Quality Plan defines the design centres for all design work and sets out the procedures and checks which are undertaken to ensure that:

1) All necessary calculations are prepared and checked, submitted and proved prior to the commencement of final design.
2) All design accords with the design intent of the project architects.
3) All designs are fully co-ordinated.
4) All HAZ Marble Design work is fully co-ordinated with other contractors.
5) All drawings are prepared and submitted in accordance with the procedures laid down by the Project Architects.
6) All drawings are fully checked for correctness prior to submittal.
7) Any variance from approved construction drawings resulting from changes on site are subject to the same scrutinies as original designs and all such changes together with back up calculations are fully recorded for As Built documentation purposes.

The Quarry:

The Subcontractor shall visit the Quarry by the client to supply the required material for the project to make sure the supplier has sufficient resources, proper means of production and capacity required for the job.

The quality plan identifies the quarry location and sets out details of the type of stone and its performance criteria. It also sets out:

1) Controls and tests to be carried out on the quarried material and test centre location.
2) Conformity requirements of quarried material, permitted faults etc.
3) Inspections to be carried out and the frequency of the inspections.
4) Information requirements to the client.
5) Inspection forms and inspections for their use.


The Subcontractor shall visit the manufacturer and quality of the polished slabs and cut to size material. Cutting tolerances to follow ASTM standards; thickness +/-2mm, size +/-1.5mm, diagonal +/-2mm.

The Subcontractor shall also verify that the manufacturer has the proper means for cutting, polishing, flaming, sandblasting and producing special details required for the project. The daily production rate of the manufacturer shall also play an important role in determining the capability of the manufacturer.

The manufacturing of the material will be done according to the cutting lists prepared by the subcontractor. The dowel holes on stones to be drilled according to calcuations and given to the manufacturer on the cutting sheets.


The Subcontractor shall visit the Manufacturer before very shipment and perform a quality check on the finished product. One random selected cut to size stone from each crate will be inspected thoroughly against visual defects; such as cracks and spots, surface finishing defects and cutting tolerances. It will also checked that the crating is strong and suitable for overseas transport. Polythene sheets should be provided in between the slabs to protect the surface finish. The maximum weight of the crates will be controlled in coordination with site conditions, not to exceed the capacity of available unloading and lifting equipment.

Material and Workmanship:

In addition to the above, the quality Plan also sets out the procedures and checks which are undertaken to:

1) Control the quality of all stone purchased and used on the project.
2) Control the quality of any precast units or any subframes used in the project.
3) Control the identification of stone, precast units, fixings and materials incorporated in the project.
4) Ensure all fixings, insulation and miscellaneous materials purchased and incorporated in the project are satisfactory for the purpose.
5) Carry out all tests required to show that the materials and workmanship incorporated in the Project conform to Contract Performance specifications and on to the client all such tests results for his future reference.
6) Carry out random and formal checks of the work in progress to ensure conformity with the detailed requirements of the Contract and to identify any system which fail to conform and record corrective action taken.

Documentation and Administration:

The quality Plan defines communication channels and sets out the procedures and checks which are undertaken to:

1) Ensure the passage of information quickly and correctly between communication points.
2) Control the flow of project documentation.
3) Maintain clear and complete project records and ensure that information is easily retrievable from those records.
4) Create and maintain day files and registers.
5) Record all changes, variation orders and instructions which relate to the project and ensure that all changes, variations and instructions are implemented.
6) Maintain an up to date record of management, Subcontractors, Supplies and project personal.
7) Ensure that revisions to the Quality Plan are controlled and issued.

Installation phase:

The Subcontractor shall establish a Quality Control department on site to control the quality of the finished product. The following should be checked regularly.

1) Proper unloading, handling and stocking of the material to ensure minimum wastage.
2) Levels, grid lines, alignment and plump lines during installation at every row. The base given by the Main Contractor. The Subcontractor will transfer and mark these reference points and lines at every row. Every row must be checked before proceeding.
3) The required torque should be applied to expansion bolts.
4) Material prepared to be installed for an elevation should be uniform in colour and visual defects.
5) Cavity.

The quality control will also ensure that the installation is done in accordance to specifications. If the irregularities encountered on the concrete is higher than allowed and considered in the calculation of load bearing the fixing system, subcontractor shall inform the Main Contractor of suitable system and provide the related structural calculations for review.

Handover phase:

1) Every elevation should be checked after completion and comment on remedial works, if required.
2) After cleaning the completed elevation, but before dismantled the scaffolding the completed elevation elevation should be released for preliminary hand over.
3) The protection of the completed elevations after preliminary hand over and acceptance will be under the responsibility of the main contractor until final hand over.