What is site preparation in construction?
Proper site prep is the phase of the build process that must be completed before other construction activities proceed. The construction project's success depends on how well this step is carried out, and a site prep contractor should be involved in this task.
Site preparation involves determining the appropriateness of the selected land for its intended use:
- Is the property large enough to put the structure on and have sufficient setbacks?
- Will the building interfere with existing utility lines?
- Are current traffic needs on the property affected by the proposed location?
- Is the soil suitable for construction and access road construction?
- Do easements exist that the new structure could interfere with?
These are just a few issues to consider during the initial prep work. We will help you prepare for your new build by covering the major steps and guiding you through the process.
Construction site preparation checklist
Here's an overview of the steps involved in building site preparation for construction projects.
STEP 1 - Site Surveying
Surveying a site and drawing out the exact area where the structure is to be erected is the responsibility of a surveyor. Most localities will require a site survey showing where the new building sits and its distance from existing structures and property lines.
This survey will also indicate where the septic system will be placed if that is a part of the project.
STEP 2 - Soil Testing and Analysis
When buying new land, you should have the soil tested and analyzed before the purchase is finalized. If you already own the property, soil testing must still be completed. The test aims to see if the land can absorb water and whether it can support the proposed structure. There are two different tests.
The water test is referred to as a perc test, which is short for a percolation test. This will determine if the land will drain water at a prescribed rate to prevent marsh-type conditions on the property and to support a septic system. A county health inspector is usually present to ensure the test is done correctly.
Soil Investigation and Site Analysis
During the planning stage, you must first conduct a field investigation. This involves gathering information, assessing data, and reporting potential hazards beneath the ground that have not been revealed. In most cases, construction issues are caused by unexpected ground conditions that could have been avoided if a proper site investigation had been conducted.
A geotechnical site investigation is performed by a geotechnical engineer (soils) working with a geotechnical contractor. A soil engineer is a professional who analyzes the physical properties of soil and determines its adequacy for construction. The engineer provides recommendations for the loadbearing capacity of the soil, which is used in the design of the structure's foundations. The engineer helps you avoid problem soils, such as expansive clays, saving you time and money.
STEP 3 - Site Clearing and Possible Demolition
In this step, the area is cleared. The site prep contractor will ensure that a rough grade is established for the entire site. This can include tearing down existing structures, tree and root removal, and removal of any existing underground construction elements.
STEP 4- Site Plan Design
A site plan, also known as a plot plan, is a two-dimensional map depicting the buildings that will be constructed on a property plot. A professional land surveyor prepares the plan. The plan will show the position and orientation of your structure on the ground, including roads, sidewalks, landscaping features, and water supply lines.
Clear property lines are the first thing seen in a plan drawing of the job site. Then come the exact distances between important structures and landscape elements. It addresses all that lies within the boundaries of the property.
STEP 5 - Grading and Soil Preparation
Excavation begins once the engineering plan (provided by your building supplier) and site-plan have been approved and all permits have been obtained. Breaking ground for a new structure is generally not allowed before obtaining a building permit. Grading will involve bringing the site to a level from which foundation excavation will proceed. During the site clearing phase, this may have been accomplished, but the land is often cleared, not brought to the final grade.
Additional fill may have to be brought in during the grading process if needed to raise the soil level to the desired elevation and ensure proper drainage. In some cases, soil from prior excavation could be reused for the same purpose. Either way, the fill must be compacted in accordance with the soil engineer’s recommendations and code provisions. Proper compaction of the soil at the base of the foundation is critical. Not only is it required by the codes, but it also prevents settlement of the structure and other problems in foundations and concrete slabs on grade.
STEP 6- Run Services to the Job Site
Utilities will be run to the site at this project stage. This will require another set of professionals to come to your site and identify existing power, water, or gas lines nearby. A licensed contractor must obtain the necessary permits to extend the gas and electric lines to the site.
Check with your plumber to ensure your current pump and bladder system can handle the new load if you use an existing well as a water source.
How long does it take to prepare a site for construction?
When the plans are drawn, evaluations completed, and permits obtained; construction can begin! So, how long should this process take? For most build projects, getting the site ready for construction will last between 1 and 2 months. However, obtaining the necessary permits in some jurisdictions might take much longer, so check with your local building department.
What does site preparation cost?
Preparation cost estimates should help further define your budget for the entire project; the estimates will vary by state and local conditions. The following very rough costs are given as a guideline and based on the square footage of the building, not the lot size. Your actual costs will likely vary.
|Square Footage||Clearing||Surveying||Soil Testing||Plan Design||Grading|
NOTE: If there is no power at your job site, utility costs can range from $10,000 to over $30,000, depending on your location and proximity to public utility connections. If there is power at your site, a temporary power pole could cost $1,700-$4,500.
For More on the Build Process
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