Adding an Addition Above Your Garage-Second Story
January 31st, 2012Do you have a large attached garage with vaulted ceilings and lots of wide open space between the garage roof rafters(the lumber that is under the roofing) and ceiling joists? If so, you may have a “diamond in the rough” if you are in need of more living space for your home.
One of the most cost affordable and best ways to add more living space to your home is to build a room addition over your existing attached garage. Room additions over garages include such finished spaces as bonus rooms, home offices, in-law apartments, and billiard rooms.
Ingress/Egress into Second Story Room Addition over Garage
If you were to complete a second story room addition above the garage you first need to figure out how you are going to ingress/egress it. For example, is there an existing stair well that already leads to the garage loft area, or does it already have an entranceway via the main home? If there are no current Ingress/Egresses into the garage loft area, then you will need to figure out how to enter into the space. For the best return on investment, ingress/egress should be via the main home, and not via a stair well into the downstairs garage area. The key to the entrance is to be sure the elevation of the floor in the existing home matches the finished floor elevation of the new addition. Usually you can just push a rod through the existing interior wall at the finished floor height and use it to build the floor joists in the new second story addition.
If you have a garage that has the possibility of supporting a second story room addition, there are a few key items that you first need to consider before jumping into such a project.
Garage Ceiling Joists
Garage ceiling joists are frequently not sized to code for finished living space above them. Thus they cannot support the weight of a finished room addition. Consequently it may be necessary to sister (or marry) larger ceiling joists to the existing garage ceiling joists. And if the garage ceiling joists are too low, you may need to frame in new floor joists for the new addition. You will need to check with your local building inspector to determine if Sistering will be required.
Expected Second Story Ceiling Heights above Garage
Due to the fact that you are planning to create a room addition in an otherwise large attic area, chances are you will have height / head room issues. Items that will need to be considered are installing knee walls and collar ties to “square up” the room. Knee walls will shrink the living space of the room addition, however if done smartly, built-in cabinets and closets can be melded into these knee wall areas.
Regarding collar ties, collar ties will allow you to create a flat ceiling in at least a portion of the room addition, and will provide more structural support to the roof rafters. Where you position the collar ties, will dictate the maximum height of the room
Plumbing a Room Addition over a Garage
If you are planning an in-law apartment, bathroom, and/or kitchen area in the room addition above the garage, you will need to consider where existing drains and vent stacks exist within the home. Adding plumbing to a room addition over a garage can be a tricky endeavor so make sure you meet with your plumber during the planning phase of your project.
We have built many second story additions in a local development, Bear Trap Dunes. Here are some sample floor plans and finished front views of them. You can see more photos on our sites;
www.resortpointe.com/renovations
www.beartrapdunesadditions.com
www.resortpointecustomhomes.com
700 Sq Ft 2nd story addition The master BR in Second Story addition Master Bath in the Second Story Addition
Second Story Addition Floor Plan Build Above the Garage Another smaller Garage Addition












