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STRUCTURAL ENGINEERING/ STRUCTURAL ENGINEERS

Our structural engineers with experience on a wide range of projects provide expert support at every stage of your project. We work together with other professionals on projects ranging from a single beam for house alterations, high-end architecturally designed residential houses, commercial structures, seismic assessment of existing buildings (ISA and DSA), retaining wall design, earthquake damage assessment, and pre-purchase structural assessment for insurance purposes.

Our professional structural engineers provide the following specialist services:

  • Design of beams, columns, frames using timber, steel and concrete,
  • Design of foundation system for TC1, TC2, TC3 and mass movement sites,
  • Design of commercial and industrial buildings, including portal frame, tilt panels and foundations (shallow or deep piled foundations),
  • Design of structural members for all types of residential developments,
  • Pre-purchase structural assessments reports to confirm the structural conditions of residential structures, commercial and industrial buildings,
  • Structural design of retaining walls, including timber pole, masonry, and concrete walls with or without tiebacks,
  • Initial and detailed seismic assessments (ISA and DSA) to determine the seismic strength in terms of a percentage of New Building Standard (%NBS),
  • Design of seismic strengthening to meet 34%NBS, 67%NBS or 100%NBS,
  • Damage assessment reports and remedial works for residential, commercial, and industrial buildings.
  • Design of foundation re-levelling works, including full structural and geotechnical package and construction monitoring (PS1 and PS4),
  • Construction monitoring and PS4,
  • Design of temporary structures such as sheet pile, scaffolding and propping design.

Please contact our experienced chartered structural engineer below for further information:

Akram Kawa, 0221079901, akram@geotestgroup.co.nz

SCOPE OF SPECIFIC STRUCTURAL ENGINEERING SERVICES

DETAILED STRUCTURAL DESIGN

We provide structural design package from concept to completion for new residential and commercial structures, foundations design, retaining walls, portal frames, bracing design for new residential structures, alteration and/or extension to existing commercial, industrial or residential structures, and repairs.

The requirement for a detailed design is assessed on a case-by-case basis. The design will be determined by geotechnical conditions of the site, the proposed shape of the building, architectural layout, and preferred construction material such as steel, timber, concrete, or masonry. Our structural design package will include:

  • Structural drawings and specifications,
  • Design Features Report (DFR),
  • Design calculations
  • Producer Statement PS1,
  • Design LBP Memo,
  • Safety in Design
  • Durability letter – B2 (if required).

We will also carry out structural construction monitoring and provide a producer statement PS4 (construction review), which is required by local authorities as part of the Code of Compliance Application and approval.

Prices will be variable depending on the complexity of each project. We will be able to provide fixed prices for smaller projects.

Our turnaround time is reasonably short. Depending on the size of each project, we can complete our design package within 4 weeks after confirmation of the contract provided that all information is available (geotechnical and architectural).

SEISMIC ASSESSMENT (ISA & DSA – %NBS)

The seismic assessment of existing buildings is required throughout New Zealand to identify Earthquake Prone Buildings and manage the risk in a timely manner. The assessment will be done as per the MBIE Guidelines for earthquake-prone building regulations and EPB Methodology that came into force on 1 July 2017. The guidelines provide a method for two-level of assessments:

  • Initial Seismic Assessment (ISA) – This is for a broad indication of the likely level of seismic performance of a building. It involves a site inspection, a desktop review of the building property file and carrying out the IEP spreadsheet analysis followed by a short report.
  • Detailed Seismic Assessment (DSA) – This will involve detailed assessment of all structural components in a building that will impact the seismic performance of the building. In this process, a hierarchy of strength and potential structural weaknesses will be identified. Once this information is available, the seismic strengthening design becomes easier.

Both seismic assessment methods rate the building as a percentage of the new building standard (%NBS) applied to an equivalent new building at the same time. A building is an Earthquake Prone Building if the seismic rating is <34%NBS. A DSA is required if the ISA identifies the building as having a seismic rating of <34%NBS. For seismic assessment, the new building standard refers to the minimum life safety performance requirements of Building Code B1-Structure.

Due to the variable nature of each building, we are unable to offer these services for a fixed price.

Depending on our current workloads, our turnaround time for an ISA is two weeks.

STRUCTURAL INSPECTION & REPAIRS

Our structural engineers have a wide range of experience with structural assessment of damaged houses caused by the Canterbury and Kaikoura Earthquakes. This is required to support EQC and/or insurance claims for the remediation of earthquake-related damages.

Our assessment includes a visual inspection of the building, a floor-level survey, a verticality survey of the walls and columns, a level survey of the door heads, benchtops, and windowsills.

As part of the repairs, we provide a full structural design package for consenting purposes, which includes:

  • Structural drawings for foundation relevelling and crack repairs (if required),
  • Geotechnical letter Provided that onsite data is available,
  • Design calculations,
  • Design Features Report,
  • Safety in design,
  • PS1, and
  • Design LBP Memo.

Our price for foundation repairs for a typical standard house is estimated at $1,650+GST. The fee for a structural inspection is variable, depending on the size of the house. However, for a standard inspection, our fee will start from $1,450+GST.

TEMPORARY WORK DESIGN

We provide a comprehensive service of temporary work design for scaffolding and sheet piling. Our experienced team will develop solutions to ensure your work is completed efficiently and safely. As part of our temporary work design, we provide design calculations and verifications, sketches, report and PS1 sign off.

SHEET PILING DESIGN:

Our structural engineers have a wide experience including sheet pile design. Sheet piling is often required for temporarily supporting the side of trenches, basement excavations, excavation adjacent to an existing building, and as a retaining structure for supporting a crane platform. Our engineers have been involved with various sheet piling projects with a maximum excavation depth of 7.5m below ground level. The sheet pile can be installed as either temporary or permanent structures.

Our approach for the design of sheet pile is to:

  • Carry out site visit to understand the site conditions and assess the risk,
  • Review the geotechnical report,
  • Carry out design calculations to obtain the loading demand,
  • Check sheet pile sections and embedment depth for the obtained loading demands,
  • Check deflections and tolerances,
  • Provide report, engineering sign off and sketches.

Scaffolding Design:

Our structural engineers provide scaffolding structures that require engineering design when they are shrink-wrapped or supporting a loading platform. Our skilled team has a wide range of design experience with scaffolding structures. Whether your project is small or large, we can design, verify and sign off your scaffolding structure.

Our approach to scaffolding is to:

  • Carry out site visits to discuss your specific needs, assess the site conditions and the layout of the scaffolding,
  • Carryout design calculations for the proposed scaffolding,
  • And provide design documentation including PS1 sign off, design recommendation letter and design calculations.

For further information and costing, please contact our Chartered Professional Engineer,

Akram Kawa on 0221079901, akram@geotestgroup.co.nz