Thinking of installing a parapet wall for your balcony?
In this guide, we’ll share with you what a parapet is mainly used for its benefits and the risks that come with installing one.
What Is a Parapet Wall?
Put simply, a parapet wall (also referred to as fire walls) is an extended wall that extends above your roof level. This gives street viewers the illusion that a building is taller than its actual height.
Parapet walls also act as a barrier for your roof edge and can also be useful when constructing terraces, walkways, balconies, etc.
Back then, these walls served as a protective layer against ground attacks of military forces; however, that’s not the case anymore today. [R]
History and aesthetics aside, this wall serves various protective functions and benefits for buildings, which we’ll discuss in the next section.
Benefits of a Parapet Wall
In this section, we’ll share with you how installing a parapet wall can benefit your roof system or building.
Wind Resistance
When strong winds blow against your roof or building, the vortices produced target your roof edges. With enough power, these forces can lift your roof edge and damage your roof system.
These walls help prevent elevated wind pressure and provide better protection to your roof structure and roof assemblies.
Protection Against Fire
Fire is a dangerous element your roofing membrane is especially vulnerable to. These walls help prevent the fire from spreading to the exterior of your building and roof structure.
Prevents Water Leaks & Damage
You might have noticed large pools of rainwater on top of your roof after a heavy storm. Left untreated, these pools of water can seep into your walls and cause further damage to your roof.
Found at the bottom of your parapet is a scupper drain, which directs rainwater to flow off to the side of your roof structure or building instead of pooling on your roof and, worst-case scenario, causing your roof structure to collapse.
Vapor Pressure Relief
Some buildings, typically older ones, will have parapets that provide vapor pressure relief.
When installing any roofing membrane, it’s vital to ensure no water enters the membrane since it can easily seep beneath your shingles left unprotected.
Parapets that provide vapor pressure relief direct water to the roof edge, which allows it to exit away from any vulnerable area of your roof.
Hazards of Parapet Walls
As beneficial as installing walls can be, it’s worth noting it’s also constantly exposed to various weather elements. During fire operations, these walls are prone to failing.
That’s not all. Typically, this wall will be supported by a horizontal steel l-beam. The primary concern with using a horizontal steel I-beam is fire.
We know that metal and heat do not go well together. Although steel is no ordinary metal, it still has a breaking point. When fire spreads and reaches your loft or attic, for example, the fire will eventually reach the steel beam.
Exposure to high heat will cause the steel beam to expand and, therefore, cause the wall to collapse. That being said, we’ve come prepared in this review.
The next section will discuss tips on how to properly maintain these walls and keep them from collapsing.
Tips to Remember
Before installing a parapet wall, bear these simple tips in mind:
Tip #1
Dress the roof membrane over the parapet walls along with a roofing edge trim on the exterior edges of your parapet.
It’s important to note that any waterproof membrane you install works hand-in-hand with these walls. A poorly installed membrane will be a sitting duck in your roof and will be useless in protecting your roof.
Tip #2
These walls absorb heat rather quickly, so proper and strict monitoring is an absolute necessity.
Heat causes paint to become flat [R], which destroys any barrier between the surface and moisture. To solve this issue, be sure to use a waterproofer to seal the walls and a satin finish for effective sealing.
Tip #3
Never assume a parapet can withstand the weight or load of elemental forces and added live loads. There’s a reason why this wall and your roof structure, in general, require regular maintenance and monitoring.
Tip #4
During fire operations, set at least one collapse zone ahead of time. Monitor the walls for any signs of cracking, stress, or wear and tear. These walls could fail at any given time, even after the fire has been contained.
Tip #5
In case of a fire, always sound the roof before stepping and walking on it. It’s possible that due to stress and other factors, the wall will collapse upon impact.
Using a 6, 8, or 10-foot roofhook is the best tool when sounding a roof. Also, don’t just tap the surface. Strike the surface with enough force to measure its stability.
Conclusion
Before conducting a parapet wall repair, follow the proper building code and talk to your roofer to get the maximum protection for your roof structure.
We hope this guide was able to help you understand everything there is to know about parapet walls, its benefits, and risks! We’d love to hear your thoughts in the comments section below!