How To Make a Foundation Plan for a House

Giovanni Valle is a licensed architect and LEED-accredited professional and is certified by the National Council of Architectural Registration Boards (NCARB). He is the author and managing editor of various digital publications, including BuilderSpace, Your Own Architect, and Interiors Place.

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Foundation plans are plan-view drawings showing the location of footings, piers, foundation walls, columns, and supporting beams. While the sizing and details of foundation elements are generally designed by a structural engineer, particularly on larger buildings, they are also included as part of the architectural set.

A foundation plan is crucial for a house to have a stable foundation to handle its weight and any other external forces that might affect it. This includes things like strong winds, rain, and earthquakes. A foundation plan is usually created simultaneously with a floor plan and building section but may also be made independently.

If you are creating a full architectural set of drawings, you will need to include a foundation plan. Once you have the structural details and spacing requirements from the structural engineer, you can lay out the elements on the plan based on this information and the dimensions of the home.

Here are some common steps when creating a foundation plan for a house:

Choose a location for the house.
Determine the number of rooms you want.
Plan for fixtures.
Draw the floor plan.
Add vertical circulation and structural elements like stairs or decks.
Figure out where utilities like water and electricity go.

Making a foundation plan can be a significant challenge, especially when doing it for the first time. However, following the mentioned steps can make the process easier. Keep reading to learn more about each stage and the crucial factors to consider when making a foundation plan.

Create the Foundation Plan Only Once the Floor Plan is Set

While floor plans are constantly shifting and being adjusted, it’s best to get this plan as close to possible to being finalized so that you don’t have to go back and adjust the foundation plan.

It might also be helpful to have the building sections as close to finalized as possible for the same reason. When drawing the foundation plan, sections also help locate and the various elements of the foundation.

Wall locations and the sizing of rooms have a direct impact on the foundation layout below. Likewise, the thickness of loadbearing walls, in particular at the perimeter of the house affects the width of the foundation walls.

Given the importance of the floor plan in establishing a foundation plan, we’ll take a more detailed look at the steps involved in this phase and how it eventually translates into a foundation plan. But first, let’s review the relationship between the foundation and the site upon which it rests.

1. Choose a Location for the House

This first step sets up the orientation of the home, the overall dimensions of the structure, and consequently the layout of the foundation plan.

Choose a suitable site to build the house. This spot should be relatively level and free of major obstacles, such as rocks, trees, or boulders.

Also, consider local building codes, soil conditions, drainage, and other environmental factors. This is where a structural, civil, or soils engineer can be particularly helpful.

Some areas may require a house to have a certain number of feet from a canal or river for flood protection, while others may restrict how close one can build a house to power lines and other utility poles.

2. Determine the Number of Rooms You Want

Figure out how many rooms you want your house to have, as well as what size they’ll be. This will also help guide the overall dimensions of your house.

Make sure to include doors and windows in your plan for each room and any major vertical circulation such as stairs or structural elements like decks.

It would also help to consider the sizes of the appliances you plan to install in each room, along with any plumbing fixtures. Doing this will help determine the overall square footage required for each room.

3. Plan for Fixtures

Remember that you’ll need to plan for all your appliances, fixtures, and other necessities. This includes built-in shelving and cabinets as well.

In addition to the square footage required for bedroom or bathroom spaces, don’t forget about other significant rooms such as a kitchen or garage.

Also, don’t forget to include the square footage needed for hallways and stairwells. You may use a computer program or hand-drawn sketches to help you determine the exact amount of required space for all your needs.

4. Draw the Floor Plan

If you’ve chosen a location and figured out how many rooms you want and how much space each one takes up, including access areas like doors and windows. In that case, draw up a floor plan that includes walls, doors, windows, and furniture in its proper place.

For the best results, I recommend following these steps when drawing up the plan:

Start by drawing the room’s outline. Square or rectangular rooms are easiest to create and will be easier to measure later in the process.
Draw in any doors, windows, and staircases that you plan to have in each room. These should be labeled with their dimensions.
Add a legend for each element, so it is easy to identify what they are later on.

Tip: Remember to label each door and window for its purpose. For example, there might be one door for the front or garage, another door to go inside or outside of the house, and several windows throughout.

5. Add Vertical circulation and Structural Elements Like Stairs or Decks

The next step is to add in any vertical circulation and structural elements that might affect your foundation plan. This could include things like staircases or decks, which might require special planning depending on their size and location in relation to the house.

The location of bearing walls and their thickness also needs to be taken into account as this will affect the layout and width of the foundation walls. Keep in mind, for exterior walls, that any surface added to the wall could require widening the foundation wall.

Also, remember to consider drainage when planning for decks. If there’s a drainage problem where water would pool under the deck during rainstorms, it may be best to avoid building on that spot.

6. Figure Out Where Utilities Like Water and Electricity Go

Before you can build your foundation plan, the final step is to figure out where utilities like electricity and plumbing will go. This includes determining how many utilities will be necessary, as well as where they should be placed.

For example, if your house plan requires a septic tank or if it’ll be on a well system, you’ll want to account for the necessary space required.

This is also true for any electrical outlets and features that may require a closer access point than where you’d install your main service panel.

For more insights into these steps, I recommend reading Simplified Design of Building Foundations (available on Amazon.com). The book explains the key activities in this process, including slope stabilization, new material settlements, and how to design key foundation elements.

Crucial Factors To Consider When Making a Foundation Plan

Now that you know how to make a foundation plan for your house, there are a few crucial considerations that you should keep in mind:

Take Time and Care When Planning – When creating the drawings and sketches for your floor plan, take enough time and care to ensure you don’t miss anything. Ensure that all doors, windows, appliances, structural elements, and electrical outlets are clearly labeled and labeled correctly.

Use the Right Software – Use a computer program to help you design your foundation plan, which will give you the best results and more accurate measurements.

If you don’t have access to that kind of software, then use your judgment in sketching out the details for each room.

Be Flexible and Adaptable – Even with the best foundation plan, your house might end up looking a bit different than you first imagined. When drawing up your plan and creating sketches, be prepared to make changes along the way.

Also, keep in mind any future plans for renovations or bathroom expansions. Allow enough room for them when making your initial plan, so you can easily incorporate them into your floor plan later on.

Remember: Building a house is an expensive and time-consuming process, so you want to ensure that you don’t encounter any unexpected problems. Be flexible and adaptable throughout the entire building process, and everything should go smoothly when it comes time for construction.

Follow the Relevant Building Codes – Don’t forget to ensure that your house plan follows all building codes. You’ll need a permit to build the foundation, so you may have to present your foundation plan for approval before finalizing anything.

Final Thoughts

When planning out the foundation of your house, it’s crucial to plan everything out ahead of time. This will ensure that you don’t run into any problems down the road and can quickly correct them if necessary.

Be sure to consider all possible structural elements and room layouts beforehand to know what size they should be. Label each element as you go to ensure nothing gets overlooked.

Also, remember the best way to do this is using drafting software. This type of program will allow you to accurately measure everything beforehand to know the measurements to use.