Adding a basement next to an existing house

Adding a basement next to an existing house. If you want to enlarge your home living space then it is a good idea for you to add a basement for your house.

As we all know that building a basement, before building a house is very common these days. But we can never imagine it before building a basement next to an existing house.

So, these days nothing is impossible if you want to do anything. Of course, you need to make a plan and a proper guideline to do something different.

You can also make a contract with your nearest construction companies. As we know that these kinds of projects may bring challenges for you. But in case you want to build a basement for your house or someone else house, this content must be going to help you.

When you make a plan for a basement don’t forget to check the local building codes and get a permit for legal construction work so that you can do your project without facing any hurdles.

Adding a basement next to an existing house

adding a basement next to an existing house

Analysis of Surface Types

Before going to start anything it’s better to do some analysis of the surface type as well as foundation type. You have to analyze whether your home is suitable for adding a basement or not.

If you have a hard surface then building a basement is suitable for your home. But it may be more challenging if you have a soft muddy surface downside of your home.

On a soft muddy surface, it’s better to not leave any space around the foundation.

Even a slab-based home may put you in difficulty. As you may know that you have to do digging so it can cause demolishing the slab. You may also need to do your plumbing again because it probably existed under the slab.

Construction Companies

It is more feasible to start excavation from the outer side. But if you hire any construction company, they can lift your home or place to a near-empty place and can start building your home foundation with blocks and concrete layers.

After completing your basement you can again place your house above the basement that you lifted for a time. But, adding a basement is an expensive, time-taking, and also a complicated project to do.

One more thing is that you required space in front of your house because you need to use different tools, equipment, and machinery dor dig the basement from the outer side.

Steps to Add a Basement

If you are going to enlarge your house living space then it is a good idea for managing double space in a single limited space. While planning the procedure and designing the structure for the basement you need to know that it requires a lot of jobs instead of doing one type of job to accomplish this project.

For example, you need a skilled and expert team for building a foundation, construction, plumping, and electricians. You’ll also need a contractor to get your permit for legal work. So, you can see that this is not a project that you can do yourself.

  • Make a Space

make a space

If you want to add a basement next to an existing house then you need to keep in mind that you have to start digging from the outside of your house.

To accomplish these activities you’ll require some machinery, appliances, and tools. So, these kinds of heavy machinery want someplace to keep them on the spot and also to run them.

If you have some space like a yard or space equal to a room, then it is a very fine thing that may reduce some worry from your mind.

So, keep in mind that you need to make that area free of objects, decorative items, or any kind of thing that makes any obstruction in your work.

In case, if you don’t have a free area or you are living in a society with no free space in front of your house, then this situation may cause some complications for you.

Because it is essential for your project, you need to get some space for working. Here, we can suggest that you should request the people living near to your house if they have any yard or free space in their house.

If you have some cooperative and supportive neighbors and you can borrow some area from them, then you may find an easy way to start construction for your basement.

  • Holding or Lifting House

In this step, you have to make a plan that either you want to dig for your basement or you want to temporarily lift your house from the existing place.

Here, you can contact your expert contractor for making the best plan for you. He may give you the best idea based on your surface and foundation types.

If you choose a method of digging your house then you required a crane, jacks, blocks, and tie-down straps. This material can hold up your house to make your excavation possible.

Crane and jacks may help you to support your existing house using blocks and tie-down straps. You can follow this method if you don’t have enough space for lifting the house.

But if you choose the second method to add a basement then it required a second way. If you have a large area near to your home then this method is more suitable for you.

In this process, your professionals elevate your house and place it near the existing place using a crane. Don’t worry as it is temporary. They’ll place it back when they’ll build the basement.

Make sure that where you place your house, that area must be cleaned from any plants, obstacles, or any kind of statue.

  • Excavation Machinery & Tools

After making your plan of cleaning free space and choosing the method of excavation or lifting and moving your house, now it’s time to start digging for adding a basement.

In this step, you need to know what kind of machinery you are going to use for digging your basement. Using a backhoe for excavation is common and a quick way of digging.

But there are a lot of other types of machinery and tools that are very useful in the process of digging like loaders, excavators, augurs, or piling rigs with the help of a hummer.

While digging your basement, keep in mind that using a front loader, throw out the excavated soil to make the place clean for working easily.

Drainage & Insulation

While adding a basement to your house, make sure that you have a proper plan for a drainage system. You have to level your ground so that the water cant be stuck on the floor and can flow outside easily.

Moreover, You need to protect the walls of your basement from the inside as well as outside. So that you may prevent any kind of leakage of water from the walls and ground.

Better drainage system safe your walls and ground and maintains the strength of your basement.

Spray foam, fiberglass, and foam board are some types of insulation that you can use in your basement. As we know the insulation provides a shield and protects your property in various forms.

Plumbing & Electric Wirings

In this step, you have to make a plan about plumbing your basement. You may make a plan of building a bathroom or a kitchen for your basement. So, you have to be concerned about the access to watering.

A basement without electricity is a thing that you can’t even imagine. Lights are the most crucial part of our lives. You must have to make a plan for the assessment of the electricity for lights, fans, or using any other appliances.

Walls & Columns

walls & columns

We know that walls and columns are the things that play a major role in holding and carrying the weight of your house. You have to make sure that you may use that kind of material that makes them twice stronger.

Like you can use great stuff foam for this purpose. But it’s better to use gloves and long shoes because great stuff can get over your hands or skin.

You can also use underlayment for your basement. You can also use any kind of substance that can protect your basement from leakage and make it waterproof.

After the construction of walls and columns, you have to secure the area around the walls from the outer side. So that you can prevent your walls from soil slopes.

As adding a basement is a super expensive project. So, it will be nice to not take any kind of risk that can create problems for you in the future.

Calculate Expenses

Adding a basement to an existing house is not an easy job. It is a very challenging, time taking and very expensive project. If you want to do a rough estimate for the expenses then you can calculate it by yourself.

One square foot can charge you between 30 to 70 dollars. So it means that if you want to add 1500 square feet of the basement, then it may cost you 45000 to 105,000 dollars.

Pros of Basement

  • You can expand your living space.
  • Enlarge storage space 
  • Utilizing a single place and can get a separate living area.
  • Maximize the value of your home.

Cons of Basement

  • Highly expensive


Adding a basement next to an existing house is a super idea to enlarge your space. Before starting construction, it is better to make a full plan for the project.

Even if you hire any construction company, after these guidelines you may be able to get a clear concept of building a basement.

Make sure to get some precautionary measures while accomplishing your basement project activities.

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