Solutions for Managing Privacy in Zero Lot Line Homes

One of the biggest challenges builders face nationwide is a lack of available lot space. According to recent data from the National Association of Homebuilders (NAHB), lot availability has hit a record low. The study showed that 64 percent of builders reported the supply of lots in their markets was “low” or “very low.”

There are builders who are turning this challenge into an opportunity and tapping into a substantial niche market by building high-end, luxury zero lot line homes. Zero lot line homes are residential properties built so that one or more walls are built directly on or very near the property line. Many builders utilize a configuration commonly referred to as a “Z-Lot”, aligning the exterior walls of neighboring homes in a zigzag fashion and without side windows to create a sense of privacy. A builder in Arizona has attracted media coverage and a great deal of public interest with a plan to build more than 100 such homes in one of their developments.

So why the sudden growth in popularity for zero lot housing? Aging baby boomers and retirees are often looking for low maintenance and simplicity in their homes. Zero lot line homes can maximize the luxury features and square footage inside the home while significantly reducing or eliminating yard work and property maintenance.

The concept also has appeal to younger, urban homebuyers who may be accustomed to living in close quarters with neighbors. Zero lot line homes represent a way to move up to a freestanding house at a cost that might be more accessible to a first time homebuyer due to the reduced lot size. It also has great appeal for vacation homes, since there is no yard upkeep, but plenty of interior space.

The most critical aspect when developing zero lot line homes is managing the issue of privacy for homeowners. Visual privacy can be established with creative placement of windows and wall configurations. Sound is more difficult to manage. Although zero lot line homes typically don’t have shared walls, like a condominium or apartment, the walls are close enough to make sound management a potential challenge.

For builders who want to offer potential homebuyers the benefits of zero lot line homes and that also address the issue of privacy, there are solutions to significantly limit the passage of sound from house to house.

One traditional approach is to insulate the wall and double up the layers of drywall with a resilient channel and an acoustic clip. While this can be effective, this set up can be more complicated and heavy on materials.

Another option available to builders is to install factory laminated noise reducing drywall. This standalone product cuts and installs just like standard drywall and is specifically designed to absorb sound at a much higher level than standard drywall.

An example of a factory laminated noise reducing drywall is SilentFX® QuickCut from CertainTeed. The ½-inch or 5/8-inch board is engineered using two dense gypsum board layers sandwiching an inner layer of viscoelastic polymer. This polymer acts like a shock absorber to dampen the vibrations of sound energy as it passes through. This type of constrained layer damping (CLD) board product performs well acoustically over an extended range of frequencies, and results in increased sound transmission class (STC) ratings.

With lot shortages and a continuing homebuyer migration toward more densely populated urban centers, the zero lot line trend is poised for growth. Builders who can offer efficient, luxury designs that deliver superior interior comfort and effectively eliminate the privacy concerns inherent with zero lot line building will be at a great advantage to profit from this expanding segment.

For more information on noise-reducing drywall, please visit CertainTeed.com.