Inner West Sydney Roof Inspection Report Purpose:
Provide a roof condition report to N.C.C 2016 Vol.2, AS 1562.1, AS 1562.3, SA HB 39 2015: The installation Code for Metal Roofing and Walling and Manufacturer’s Instructions. Provide recommendations to extend longevity.
Inspection Site Gallery
Findings & Recommendations In Inner West Sydney Roof Inspection Report
- Roof area to the southern buildings displays evidence of numerous sealant applications and previous ingress issues. Plant/ A/C penetrations have caused ponding in numerous locations, resulting in corrosion and previous ingress throughout the roof. Non-compliant to SA HB39 refer 8.6.1 and AS 3500.3 refer 4.4.3.
- Non-compliant/ problematic penetrations are typical throughout the roof.
- Walkway awnings have suffered heavy foot traffic damages throughout. Severe damage / ponding is present throughout. All awning roofs require replacement.
- External sealant applications are failing in numerous areas due to continual ingress at the anti-capillary features. Roof sheeting throughout requires replacement.
- Box gutters are showing evidence of ponding throughout due to a lack of effective gradient. This ponding results in rapid corrosion of the box gutter material. Non-compliant to SA HB39 refer 5.3.2 (i) All box gutters require replacement and the fall must be adjusted to allow for complete drainage.
- Flashings have experienced external sealing and previous ingress issues throughout. All flashings and cappings are to be replaced in conjunction with the roof replacement.
- Roof valleys installed to the low pitched upper roofs are non-compliant to N.C.C Vol2. Refer 22.214.171.124 (i)
- Roof Valleys are installed on a pitch lower than 12.5-degreees. Must be designed as a box gutter with compliant discharge. (Rainwater head) The roof should be raised via Roof Raiser / Ash grid system to allow for sufficient box gutter depth.
- Soaker gutter installation to the upper roof has suffered heavy ponding and Corrosion. A box gutter should be installed in conjunction with the raised roof height as mentioned above.
- Eaves gutters are heavily ponding throughout the upper roofs. Non-compliant to AS 3500.3 refer 4.5.3. All eaves gutters require replacement and the fall must be adjusted to allow for complete drainage.
- Roof valleys installed below a pitch of 12.5 degrees are non-compliant to N.C.C Vol2 refer 126.96.36.199 (i). See above #6 for compliance. Roof must be raised to accommodate box gutter installations.
- Roof penetrations throughout are noncompliant and show evidence of previous ingress issues due to external sealant applications. Tray flashings provided have not achieved 150mm effective coverage. Non-compliant to SA HB39 table refer 8.1.4.
- Eaves gutters are ponding and suffering corrosion. Non-compliant to AS 3500.3 refer 4.5.3
- All roof penetrations are non-compliant and problematic. Ponding and anti-capillary issues are present throughout.
- Non-compliant/ problematic penetrations shown.
- Walkway roofs have suffered heavy foot traffic damages and require replacement.
- Upper roof valleys are installed below a pitch of 12.5 degrees.
- Box gutters throughout are heavily ponding and non-compliant.
- Flashings have suffered previous ingress issues and external sealant applications which will continually fail.
- Soaker gutter to the upper roof is suffering heavy ponding and corrosion.
Building Code References In Inner West Sydney Roof Inspection Report
8.6.1 Collar Flashings
Where any part of the roof surface is penetrated by any pipe, pole, duct, flue, shaft, cable or tank support, the penetration is to be flashed to prevent the entry of rainwater, and to permit the roof surface and penetrating object to expand and contract without detrimental effect to any part of the roof.
4.4.3 Corrosion due to crevices
Metal roof drainage systems and support systems shall be designed and installed to achieve
complete drainage or drying. Shielded areas capable of causing permanent ponding shall be
avoided to prevent the possibility of intense localised corrosion known as crevice corrosion.
4.5.3 Eaves gutters
Eaves gutters shall be installed as follows:
(a) Gradients Deviations from nominal gradients shall be smooth and not cause
Where a building is likely to move due to reactive soils, gradients may need to be not flatter than-
(a) I :250 to achieve an effective gradient not flatter than I :500; or
(b) I :500 to achieve an effective gradient with no permanent ponding.
Light condensation will not generally cause permanent ponding, whereas heavy condensation, particularly in conjunction with retained silt, can reduce the design lifetime of the product.
B6.5.1 Surface Damage
Badly damaged panels should be replaced and the manufacturer consulted for the best way to remove and replace the panels. Minor damage can often be repaired in situ.
B 6.5.2 Sheet Damage
A dent, split or puncture in the external skin should not be left untreated as it will accelerate corrosion and, in some insulated products, absorb water into the insulation core. On a roof, it is sometimes possible to repair by over-skinning with a matching profiled skin. All edges are to be sealed to prevent moisture getting between the two skins. On a wall, it is not usually possible to over-skin and in this instance replacement of panel is generally the preferred option. The panel manufacturer should be consulted as to the preferred option.
Roof Inspection Conclusion Based On Findings
- All roofs have reached their serviceable lifespan, are beyond repair and require replacement.
- The upper roofs must be raised to allow for the additional depth required to provide box gutter installations.
- We also recommend that the main roof areas are also raised to allow for additional box gutter depth and to allow the fall of the box gutters to be increased and drain freely.
- The Roof Raiser / Ash grid system that is proposed is capable of sustaining Solar Panel installations given their load weight does not exceed the Manufacturer’s Instructions.
- It is also imperative that the underlying support span members are steel purlins as Roof Raiser systems can not be installed to standard roof battens.
- All A/C units will require removal and reinstatement with P.V.C cowling and compliant flashings to ensure no ingress issues persist. Surrounding cladding to the lower roofs will require removal and alterations to allow for the additional roof height.