At Manor Build, we want to ensure that your new home building process is as smooth as possible. That's why we emphasize the importance of obtaining a geotech report as early as possible. These reports provide valuable insights into the ground conditions of your site, helping us determine the most suitable foundation design for your home.
What is a Geotech Report
Geotechnical reports are comprehensive documents that present the findings of a site investigation, assess ground conditions, and provide recommendations for building foundations.
They are designed to evaluate the suitability of the ground to support a proposed structure and identify any potential geotechnical hazards that may arise during or after construction. For example, they will check for any settlement, slope instability, liquefaction, or other geotechnical hazards.
Often, the Geotech report process involves the following:
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Conducting a site visit
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Drilling boreholes
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Collecting soil samples
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Performing strength tests
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Conducting laboratory analyses
Read more about Geotechnical testing here
Understanding the Importance of Geotech Reports
To make your new home building process is as smooth as possible we emphasize the importance of obtaining a geotech report when you're in the concept design phase. There are two main reasons for this.
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The first reason for this is that these reports provide valuable insights into the ground conditions of your site, helping us determine the most suitable foundation design for your home. By understanding the soil composition and potential risks, we can provide you with a fixed price for the foundations, eliminating any surprises down the line.
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Another reason is that you won't be able to obtain a building consent without it being done. In comparison to several years ago, it is now almost universally required by the council to have a current (within 2 years) geotech report to be submitted along with the building consent, making this process now a requirement.
Timber Pile Foundations in Poor Ground Conditions
Building on poor ground conditions can lead to significant challenges and budget blowouts. However, with the help of information from the geotech reports, we can address these issues proactively. Our team of skilled professionals at Manor Build, along with our trusted partners, will be able to design a simple foundation solution without excessive expense that will work for the unique conditions of your site. By doing so, we ensure that your home remains structurally sound and stable for years to come, even in challenging ground conditions.
One advantage we have is using timber pile foundations which are much easier to engineer for difficult ground conditions than a traditional concrete floor. In some cases a concrete floor will be required to have timber piles underneath it to make it stable!
Another advantage we have is that if a diaphram floor is reccomended by an engineer, we can do this without changing the price or our process, apart from asking the council to do an extra inspection in the build process. This is because our houses as standard are engineered to a diaphram floor standard.
Examples of Estimated Extra Foundation Eequirements and Costs
Note the below is based on our experience with timber pile foundations throughout our supply area. Concrete floors will cost much more to engineer and we wouldn't advise using the below guide.
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Good ground - Standard timber pile foundation built to NZS 3604:2011. (no extra cost)
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Some soft or unstable soil - Deeper piles or rammed piles (extra cost up to $5,000)
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Very unstable soil, Steep slopes - Engineered design (extra cost $5,000 to $10,000)
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Earthquake risk TC3 - Braced piles, excavated build site, diaphram floor, engineered design. (extra cost $10,000 to $30,000) Read more regarding this here
How do I get a Geotech Report?
If you're serious about going ahead with your new build project then it's the time to take action. You'll need a draft site plan showing the location and size of your build on the site. If you've been working with Manor Build we can provide this for you.
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Take your site plan into your local council and ask them for a list of geotech engineers who would be able to provide this service. They'll also be able to advise what will need to be included in the report based on your specific region. It is a good idea to talk through other aspects of the build while you're there, e.g planning restrictions, regulations.
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Ask for pricing and lead times from a range of geotech engineers. Pricing can be anywhere from $2,500 up to $5,000 depending on the requirements.
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Peg or mark the site so they know where to conduct soil checks.
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Contact Manor Build for assistance. In some regions we can point you towards people who we've worked with before.
Let Us Handle Compliance Headaches for You
Navigating the compliance pathway can be a time-consuming and overwhelming process for homeowners. At Manor Build, we aim to alleviate these headaches by helping you through the process with advice and helpful information. By having a comprehensive understanding of your site's geotechnical properties, we can streamline the compliance process and minimize delays. With our expertise and attention to detail, you can trust us to handle all the necessary paperwork and ensure your home building journey is hassle-free.
