OSD UPRCT pic

Dual Orifice vs Single Orifice OSD Tank Design in NSW

A dual orifice on-site detention tank uses two outlets to control discharge across both small and large storms, while a single orifice system relies on one. Dual orifice designs match predevelopment flow rates more accurately across the 20% to 1% AEP range, reduce overflow risk, and align with the Upper Parramatta River Catchment Trust Handbook…

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proposed terraces strata Pattern book CDC

NSW Pattern Book CDC: Plain English Guide to Approvals, Subdivision and Strata

NSW Housing Pattern Book explained. CDC vs traditional CDC, eligibility, requirements, timeline, cost, and how Torrens or strata subdivision is approved by a private certifier. Article The NSW Housing Pattern Book is a set of pre-approved housing designs. Low-rise patterns can be approved by a Complying Development Certificate (CDC) in 10 days. Mid-rise patterns use…

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pattern book devlpment nsw

What the NSW Pattern Book Actually Means for Subdivision and Certification

The NSW Pattern Book is a set of pre-approved low-rise housing designs that can move through a faster 10-day Complying Development Certificate pathway. It speeds up building approval. It does not, on its own, deliver subdivided lots or strata titles. That part still depends on a separate certification process, and most online coverage skips it.…

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subdivided residential block

Housing and Productivity Contribution NSW: What CDC Duplex Applicants Need to Know

There is a widespread misunderstanding about how the Housing and Productivity Contribution applies to CDC duplex projects, and it is costing applicants money and causing real project delays. The short version: under the latest EP&A (Housing and Productivity Contribution) Order 2024, the HPC for a CDC dual occupancy is not captured at the subdivision stage.…

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A surveyor reviewing engineering drawings on-site

Subdivision Certifier vs Council for Subdivision in NSW: What Actually Matters

Most content comparing "private certifiers" and "council" in NSW focuses on building work. For subdivision, the question is different, and the answer depends on your project pathway, not a generic comparison between two service providers. It is also worth clearing up the terminology before anything else. A Subdivision Certifier is a person registered under the…

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About Southwell Certifiers

Southwell Certifiers Pty Ltd provides independent certification services across New South Wales for Subdivision Works Certificates, Complying Development Certificates, Subdivision and Strata Certificates and Compliance Certificates.

 

Our focus is clear advice, efficient approvals and reliable certification outcomes for developers, engineers, architects, project teams and surveyors.

Contact Info

Southwell Certifiers Pty Ltd provides Dean Dehghan-Khalaji – Registered Certifier (BDC 05320)

admin@southwellcert.com.au

(02) 8734 5676

Sydney NSW

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