- July 31, 2017
Remedial works to a roof top terrace membrane by Strata Engineering Solutions in Elizabeth Bay, NSW.
PROBLEMS
The top units in this property had water ingress issues, and a new membrane was required to prevent water ingress and degradation of the concrete slab. The rooftop terrace was covered with pavers and pebbles, then a layer of geofabric, insulation, and then the membrane.
The Owners Corporation initially sought quotes from several builders, but the quotes they received had significant variations in cost, materials specified, and allowances thereof. This process had not provided a clear direction to take.
They then engaged Strata Engineering Solutions to prepare tender documentation to enable accurate pricing comparison. SES prepared the contracts and acted in a superintendent role during the works.
SOLUTION
Strata Engineering Solutions undertook an initial report outlining the problems. SES produced tender documentation for the remediation of the waterproof membrane and awarded the job to Laser Building Services and Son Waterproofing, who commenced the project in March 2016.
The concrete slab was found to be in good condition with no major cracking or spalling issues. The falls across the slab were found to be sufficient in most locations, requiring only some areas of screeding. These were marked out by SES and the contractor. As there were minimal screeding works required, the client was saved significant expense.
The remedial works involved the following:
1) Grinding up of the existing membrane to allow for the concrete substrate to be inspected and remediated as necessary.
2) Removal of the blockwork planters.
3) Re-screeding of the slab as-required.
4) Installation of a double layer bitumen waterproofing membrane with a materials warranty of 15-20 years.
5) Installation of a new geofabric, reinstatement of the insulation, and cleaning of existing pebbles and pavers.
6) Installation of screens to prevent loss of pebbles.
7) Cleaning of the AC ducting which was removed to allow for waterproofing underneath.
RESULTS
Strata Engineering Solutions had provided a long term waterproofing solution which prevented water ingress and maintained protection to the concrete slab.
The condition of the concrete slab was assessed and proven to be satisfactory. Clean pebbles and pavers were reinstated so the rooftop terrace was improved aesthetically as well as structurally.
- Concrete Defects
- Water Damage
