Structural Upgrades to Consider for Second Story Additions

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Second story additions will almost entirely alter the look and feel of a house. Homeowners should be knowledgeable about the structural upgrades to consider when completing a second-story addition. Some of these structural upgrades include the ability of the existing foundation to carry an additional load, new floor assembly, heating, and cooling systems, plumbing drains, bedrooms, and stairs.

Adding a second floor has its challenges, but for many households, this is the only way to add space. Homeowners should carefully plan the additional floor since it can add a lot of drama and character to an existing property, let alone extra space for the entire family to work on.

Upgrading Existing Foundation

Because a second story addition means having an additional mass on top of the current structure, one has to assess if the existing structure can carry the additional weight. Most of the time, however, experts suggest structurally upgrading the existing house. The current structure should be attached securely to its foundation. Likewise, the existing house should be able to withstand some earthquakes and strong winds.

New Floor

Usually, the current ceiling and ceiling joists are kept in place but since they're usually much lighter than floor joists, a new floor structure is built on top to keep added weight and disruptions off the existing structure. It also allows electrical lines and other elements to be kept in the ceiling just underneath the new floor. The problem with this is that it can result in a thicker new floor assembly that will be causing more stairs to bridge the second floor.

Heating and Cooling Systems

It is not advisable to extend the current heating and cooling systems to the new floor; it is more practical to upgrade the present system or to add a new system for the upper level. Remember that the upper portion of a house is hotter than any part of the household, so having a new cooling system will help in providing comfort in that part of the house.

Plumbing Drains

If the new floor will have bathrooms in it, one should assess how it will be connected to the existing plumbing on the first floor and how it will be vented to the roof. It can be possible to tie the plumbing of the new bathroom to those of an existing bathroom below. An alternative is to have the drains go through the main level onwards to the basement. The drain’s route, whether vertical or horizontal, must be planned well. Most of the time, the structure of the new floor is planned to accommodate the drains.


Since the stair connects two levels together, planning how it would look is very important. The stair can be used as a focal point by adding accentuating skylights. The length of the stairs is also dependent on the height from the finished floor (1st floor) to the finished floor (2nd floor).


Usually, the second floor serves to accommodate additional space for bedrooms. Recent trends, however, will have the second-floor serving space for a den or a hangout space. The second floor can also accommodate a guest room, or a nook where kids can work with their computers.