Can You Convert A Duplex Into A Triplex? Here is the answer


Owning a triplex property can be an excellent investment for you as an investor or a residential homeowner, so it makes sense that you are considering turning your duplex into a triplex. Most owners see triplex properties as a method of upping their income stream and reducing maintenance expenses. So if your question is

Can I Turn My Duplex Into A Triplex?

You can turn your duplex into a triplex and increase the value of your home. Though the conversion process can be long and tedious, the end will justify the hard work you put in. To get more knowledge on what it takes to convert a duplex into a triplex, continue reading, and you will be highly enlightened.

What To Consider When Converting Your Duplex To A Triplex

While converting a duplex to a triplex, you must consider two significant factors.

  • Zoning
    You have to find your city zoning location and check if you are in a zone that permits triplex properties. Zoning also comes with many bylaws like ratios, height restrictions, bus stops, parking lot sizes, etc. Non-compliance with the city zoning rules and necessities will affect your building permit approval.
  • House Type
    Find out if your duplex space meets the requirements of your city triplex property code? Ensure you have enough parking space or a basement to serve as a parking lot.

Is Converting Your Duplex To Triplex A Good Investment?

Yes, converting your duplex to a triplex is a good investment. Though it also comes with a few drawbacks, it is proven that triplex produces more income streams and helps in tax reduction. Apart from these, it is also a perfect home for a large family and will save you a lot of cost on renting.

Listed below are some of the advantages of converting your duplex to a triplex

  • More Income Stream
    You can rent out the triplex units. The monthly rent payment will help towards some expenses in maintenance or mortgage.
  • Family
    If you want your family closer to lend helping hands, a triplex will make that easy and give them a degree of independence.
  • Tax Deduction
    You may be able to deduct some expenses like maintenance or yard work once you rent out a unit. Read up about property tax deduction to get more insights.

Overall, a triplex offers a modicum of independence to the separate occupants of each three units.

What Are The Disadvantages Of Converting Your Duplex To A Triplex?

Turning a duplex into a triplex may be a good investment, but it also has some disadvantages. This includes having to share your space with others and even maintenance issues since big building requires more maintenance than smaller buildings. Here are the cons of converting your duplex to a triplex:

  • Owning a triplex means sharing space with others: If you are a private person renting out a triplex unit, you might encounter tenant issues. You have to be comfortable enduring different characters and will have to learn to solve conflicts politely and amicably.
  • Maintenance issues might occur: A bigger building means more maintenance, which incurs more expenses.

What Do I Need To Convert My Duplex To Triplex Legally?

Converting Your Duplex into a three-unit building is a significant project under any state building code. These are the steps to rebuild your duplex into a triplex legally.

1. Study Your State Code And City Rules

To turn your duplex into a triplex legally means to change the building use from the international residential code (IRC) to R2 occupancy (apartment) rules under the international building code (IBC). Read carefully to ensure you follow your state rules/codes and requirements.

2. Draw A Floor Plan

Draw a floor plan which you will submit after applying for a permit. Your floor plan must show the building layout with all proposed changes, level of floors, wall outlines, room dimensions, and window positions. The floor plan must also identify each room by name and show any pre-planned construction work like kitchen, windows, floors, and kitchens.

3. Apply For A Building Permit

Submit a well-detailed building application. Once you apply, an email will be sent by your city development coordinator with a request to submit your floor plan drawing.

4. Zoning And Approval Of Building Plan

Your city’s community planning and economic development (CPED) will review your project and building permit request per city zoning and state building code requirements. There might be some corrections. In such a case, you need to adjust and resubmit. Upon CPED approval, your permit will be approved and charged.

5. Building Project Approval

After completing your building project, CPED will inspect the building and update the certificate of occupancy to the triplex building. CPED will also change the unit count record to 3 in the permit records and inform the city’s waste and water department of completion.

6. Triplex Charge

Your city services will charge for your triplex property. This charge varies by region and community where you live. You can contact the city services in charge of buildings and properties to get the actual amount for your region.


How Much Will It Cost To Turn My Duplex Into A Triplex?

The cost to turn your duplex into a triplex depends on the size, type of material used, and choice of finishing. The average cost of conversion is $63,000 to $100,000. This cost covers the architectural description and permits to cleaning of the building after construction.

The price range may differ due to contractors or hikes in the price of building materials.

How Long Does It Take To Convert Duplex To Triplex?

Once the building permit is approved, converting a duplex to a triplex can take about 3-5 months, depending on the contractor’s speed. However, getting a permit can take a long time. The timeframe depends on the efficiency of your CPED and the zoning of your floor plan.

Approximately getting a building permit can take 6-12 months.

What Is A Duplex And A Triplex?

A duplex is an apartment or living area spread over two separate sections. It can either be connected by an interior staircase (if divided by floors) or by a wall (if units are on the same floor). Another name for a duplex is a maisonette. A duplex is a split image of each other on the building layout.

When a home divides into two separate dwelling places, it is a duplex.

A triplex is an extensive form of duplex with three sections instead of two. A triplex has three different exit entrances or shares one exit (in the case of a staircase). A triplex must have a separate kitchen, utility meter, bathroom, and same amenities in each section.


Whether you turn your duplex into a triplex for profit or family use, the same steps and requirements apply. Ensure you’re in the correct zone, apply for a permit, and build. Have fun as you go to ease the stress-filled part.

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