Can You Add A Basement To A House? [See The Process Involved, Pros, & Cons]

Basements & Other Rooms, Blog, Construction

It can get confusing wrapping your head around the concept of adding a basement to your house. Basements have a lot of benefits, not just for you but also for the value of the house. But can you add a basement to an already existing house?

Although it is not too common as many people seek other alternatives to get more out of their house, it is still very possible. However, there are certain factors or conditions that you must consider first.

In this article, I will write about the process involved in adding a basement to a house, its pros and cons, and other alternatives I think you should consider before commencing your plans.

Can you add a basement to an existing house?

Although the normal process of building a basement occurs when the house is still in the construction phase, it is still possible after construction. The process, however, is long, costly, and arduous. Adding a basement to an already existing house can take anywhere from 9 to 14 months before the project is completed.

How do you add a basement to a house?

1. Getting the house ready to renovate

Firstly, the house is ready for renovation. This includes clearing or removing any tree or bush that is close to the surrounding of the house. It also includes making sure that no drainage pipes or electric wires are around the building site.

A professional landscaper should be able to determine if the house is ready for renovation. Or whether or not it would be ideal to add a basement to the house in the first place.

2. Getting the house out of the way

The contractor will have to lift the house and brace the foundations so the house walls and floor are not damaged as work commences. This has to be done. Otherwise, it would be impossible for the workers to use all the necessary tools to get the job done.

The contractor may also recommend another alternative if he/she deems it preferable. Another commonly used alternative is called excavation, where an access hole for the digging equipment and workers is created through the house. Afterward, they place several supports underneath, which they later make permanent.

3. The digging process commences

After getting the house out of the way or ensuring there is clear access to the space being used, digging commences. Most contractors, after using a lift to brace the house, would simply use a backhoe.

They use the backhoe to dig the ground and take the dirt out of the way. But as I mentioned earlier, if excavation is used, the digging will have to be done manually, as a backhoe cannot be used.

4. The building process starts

After the basement space has been dug out, the building process commences. This includes adding basement walls and having plumbing done to ensure water can run easily in and out.

Also, ventilation pipes are properly installed while still ensuring the foundation is strong enough to hold all the weight. A waterproof membrane would also be installed so water doesn’t leak into the house if it rains heavily.

What are the factors to consider before adding a basement to your house?

Zonal laws: Your local zonal laws may prohibit adding a basement to houses in that region. This is usually the case for areas prone to flood. Check with zonal laws to confirm first.

Insurance policies: Before attempting to add a basement to your house, check your insurance policies first. Adding a basement to your home may void your existing home insurance policy.

The foundation of your house: Most foundations aren’t strong or sturdy enough to handle the extra weight. Have a landscaper check if your foundation is sturdy enough first.

What are the pros and cons of adding a basement to an existing house?


1. Adds living space to the house

Basements can be used for many things, but one of the main benefits is that they add extra living space. Once the basement is finished, it can be used as another room by anyone in the house, even by guests. It can also be used as a playroom for the kids, a workshop, etc.

2. Adds storage space

A basement can be used for storage, ranging from Christmas decorations to gifts. A large unfinished or partially finished basement might serve this purpose as they are more spacious.

3. Adds value to your home

Although it would not add as much as a similarly sized ground-floor living space, it does add value to the house. However, its value will be higher if it is actually a finished basement.


1. High costs

The cost of adding a basement to an already existing house can be quite high. There is a lot of complexity in lifting the house and ensuring the safety of the workers; therefore, it costs more than one would expect.

2. Pest

Insects and rodents find the basement to be a very attractive spot, mainly because of its high moisture content and dim lighting. Once they start dwelling there, it’s only a matter of time till they find their way to the upper level of the house.


Do basements need foundations?

Yes, they do. The foundation is actually one of the most important parts of the construction.

Can you fill in the basement of a house?

Yes, you can. However, filling a basement may damage the structural integrity. So, it is best to seek the insight of a professional engineer first.

In summary – Can you add a basement to a house?

The simple answer is yes. However, there are many factors you must consider before commencing this plan. For example, if the zonal law permits it, if the insurance policy for your home permits it, or if the foundation is sturdy enough.

That being said, considering the many processes and finances involved in this process, people seek alternatives. People simply invest the funds in a barn or garage or remodel the house so it can be spacious. This is why seeing a basement added after a home is built is kind of rare.

I believe you found this article insightful. If you did, visit Samkinsconstruction for more insightful content today.

Thanks for reading.

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