Building a quality home starts with dirt. It doesn’t sound glamorous, but proper site or land prep is the foundation for successful home construction. Assuming you’ve already purchased architectural plans or hired an architect, your next step is preparing the land itself. Here’s a rough timeline of the steps between purchasing a piece of land and pouring a new foundation.
The bottom line: new construction home site prep is probably more pricey, time-consuming, and involved than you expected. Budget up to two months total for this crucial phase to guarantee a stable build that meets local building requirements.
1. Investigate + Analyze
When it comes to construction, the strength of the soil is crucial. Strong soil is made of sand or gravel. Even after exposure to moisture, it won’t expand or contract much. On the other hand, weak soil—heavy silt or soft clay—is likely to expand, contract, and erode. Since weak soil can lead to a cracked and crumbling foundation, it’s essential to prioritize soil quality when investigating a site for land prep.
Before construction begins you’ll need to hire a soil engineer to collect and test soil samples. This step ensures that there aren't any chemical or physical conditions present that could damage your home. A proper soil analysis will determine three major things:
- Soil reactivity: How much the soil is likely to move, expand, and contract
- Soil bearing capacity: The weight the soil can support
- Chemical makeup: Whether there are any toxins or contaminants present in the soil
If the engineer finds that the soil contains toxins and contaminants (i.e., lead, arsenic, zinc, barium, copper, cadmium), they’ll likely recommend that you don’t move ahead with the project. If the soil isn’t toxic, they will suggest ways to make up for weak soil or any other issues they find. Common suggestions/solutions include replacing or grading soil, draining the land extensively, and including foundation and earth supports.
After the engineer’s analysis has been completed they will create a report to be submitted when applying for building permits.
Whenever you plan a significant improvement to a parcel of land, you need to know the plot’s exact boundaries, as well as the local laws. If you move ahead with construction but aren’t in compliance with regulations, you face the potential for legal issues that waste money and time.
You can avoid these outcomes by hiring a land surveyor to produce a boundary or mortgage survey. This will reveal exact property lines, improvements, and encroachments. It will also include information on easements (which allow third parties to access your land) and setbacks (which limit where structures can be built on the property). Don’t rely on fences or natural barriers (such as hedges) as property line markers.
If the property is within a subdivision, you might need a standard lot and block boundary survey (also called a recorded plat or recorded map survey). These apply to parcels in planned suburban developments with lot/block legal descriptions.
For parcels in potential flood zones, get an elevation certificate. This document will shed light on the risk of flood and may reduce flood insurance premiums. To determine whether a property is in a flood zone, visit your county property appraiser site.
3. Check Underground
Before breaking ground, make sure the property isn’t host to underground utility lines. (You can do this by calling 811 or visiting call811.com—the national “call-before-you-dig” hotline. If your property does have utility lines running under it, you’ll need to follow local regulations for maintaining proper distance and avoiding them during the excavation process.
Based on your architect’s drawings or blueprints and site plan, you or your general contractor will file for building permits. Whoever files for the permits will be the party that is legally responsible for the project.
For the local building department to approve your plan, your proposed structure must comply with zoning requirements, including setbacks and easements. Your plans must also satisfy regulations regarding grading (changing the contour of the land), septic systems, electrical and plumbing, and more. If the land doesn’t have access to water, power, and sewage, connecting to the grid will add significant expense. You’ll need to determine whether a well needs to be drilled, power lines run, and septic system installed (if there’s no sewer).
If necessary, your GC will need to bring in dumpsters, shipping containers, and portable toilets. They’ll also need to create access roads for workers and construction vehicles. Other than renting a shipping container to keep furniture on-site during construction, these expenses should be covered by your GC (but are almost certainly built into the final bill you’ll receive from them).
6. Silt Fence
Silt fences surround construction sites and help to control erosion. Composed of posts and permeable fabric, they’re required to prevent your site’s dirt from clogging sewers and pouring into streets and neighboring bodies of water. Silt fences perform an essential function and require that trenches be dug. You’ll want to enlist professionals to use an excavator to dig trenches.
If you’ve hired a GC, they’ll be responsible for installing the silt fence.
During this phase, workers demolish or remove structures, trees (including stumps), and rocks. To remove roots, workers often rely on an excavator. Uprooting bedrock can require blasting, and costs can add up quickly. If retaining any structures or parts of structures (like a chimney), a building engineer must make ensure their stability. Demolition work will also cost extra.
After this work is complete your GC will dispose of debris. Be sure to check local laws before burning or burying refuse, and consider reusing some of the debris if possible. Trees can be used for firewood, dirt for filling low areas, topsoil for gardening, and rocks for hardscaping.
Usually, a surveyor and the GC will install stakes and stringlines to mark exactly where the home will be built. This transfer of the building plans from paper to dirt lets the excavator know exactly where to dig for the foundation. Based on the elevation reference point included in the land survey, they’ll also set up a builder’s level. This will help them make sure the foundation and sill levels are set correctly.
9. Rough Grading
Workers excavating or digging the building site will move the earth to make room for the foundation and driveway. They’ll generally use some of the excavated dirt to form an evenly graded surface, to bolster the foundation, and for landscaping. (If the soil is silt or clay, which don’t drain well, it will likely be removed from the construction site.)
When leveling the lot, builders will position the land surrounding the house so that it slopes away to allow for drainage control and to prevent erosion.
If your property will not be hooked up to a town sewer, you’ll need to put in a septic system. The first step in this process is to make sure the parcel passes a perc test, which shows how long water takes to drain from a test pit. A passing score is required to receive a septic permit.