Finished Attics, Part 1: Zoning & Planning
Updated: Apr 9, 2020
As home prices in NJ appreciate so does the value of every square foot of usable space within the home. Thus, the unused space of an unfinished attic becomes a tempting investment opportunity for homeowners to increase the value and usability of their home.
Our Summit, NJ clients used the attic space above their garage to create this master suite (left) (Murphy Construction, In House Photography.) Just put in a stair and drywall the space, right? As simple as it may seem, it is not that easy. I’ve broken down an overview of finished attics into 3 parts: Zoning & Planning, Stairs & Windows, and Construction.
Finished Attics: Zoning & Planning
Before jumping in to start designing the new dream space on your 3rd floor, it is critical to understand what the laws are for your municipality regarding finished attics. In New Jersey, home heights are defined by both actual height (in vertical feet) as well as stories.
Stories are defined by each municipality. Generally (in NJ) basements would not be considered a story, but some municipalities may count walk-out basements as a story. We typically see zoning ordinances allowing 2 and 2.5 story homes. Each municipality is different, but towns limiting the height to 2 stories (like Maplewood, NJ) will generally allow a finished attic that is less than 1/3 of the square feet of the 2nd floor. Towns limiting to 2.5 stories will generally allow a finished attic that is less than 1/2 the square footage of the 2nd floor. At this point, you may be scratching your head thinking, “But my attic floor space is the same size as my 2nd floor space - how could it ever be only 1/3 or 1/2 of my 2nd floor?” The answer is based on height “habitability”. Code defines habitable space height as being at or above 7 ft. Thus, if your home has a typical sloped roof, the habitable portion of the floor area does not start until the roof rafters are at 7’ high and above. Thus, it is generally easy to show that the proposed finished attic space (floor area beneath heights of 7ft high and above) is less than 1/2 or 1/3 of the 2nd floor.
The absence of enough habitable height can, however, prevent an attic from being finished. Code requires that any habitable space have at least 4ft by 7ft of habitable height space. Thus, if the bottom of the roof ridge of your attic is at 8.5ft or lower from the attic floor, it is unlikely that the sloping roof on either side would open up enough to provide 4 ft of width; in this situation, the roof would need to be raised.
In the project on the left (currently under construction) the existing front portion of the home (to the right) did not have sufficient width to be considered "habitable". With the rear addition and dormers we were able to make the back half attic legally habitable.
What rooms will you have in your attic? Aesthetically, the sloped ceilings of attics can provide beautiful, unique spaces and the views from the higher windows can be stunning.
Bedrooms, Home Office: Third floor bedrooms can be ideal for guest rooms, given they are separated from the main family bedrooms on the 2nd floor. They can also be great bedrooms for older children, who may like the independence of being on another floor. Many homeowners, particularly those with older children, remodel their attic to be a large master suite. The areas underneath the sloping roof rafters can be great areas for built-ins for televisions or storage. The additional stairs of 3rd floor bedrooms may be less desirable for older users. Also, many parents will always want to be on the same floor as their children. Home offices are also popular given the privacy that a 3rd floor can offer.
The master bedroom on the left in Verona features refurbished original casement windows, vaulted ceilings, and exposed rafter ties. (Barnett Design Build construction, Jason Wood Interiors & Sean Raneiri photography). The bedroom on the right includes a central stair, a large space on one side for the bedroom and office, and a large sitting room on the opposite side (Barnett Design Build construction).
Baths: Of course, bathrooms on the same level as bedrooms are always preferred, although not code-required. Sloped ceilings can make for unique bath layouts, as the head height of each plumbing appliance (toilet, tub, shower, vanity) is specific to certain areas around the appliance itself.
Family Rooms: The combination of the expansive space, vaulted ceilings and potential large picture windows and views make family rooms ideal choices for attic utilization. Two of our attic family rooms are shown below. On the left is a massive 3rd story space in Montrose Park, South Orange, NJ (Tillou construction.) On the right is a finished attic in Verona featuring a new staircase and a Palladian window (Barnett Design Build construction, Sean Raneiri photography)
With the zoning analysis completed and the desired spaces determined, we have to figure out how to get up there and how we will actually construct the space.