Flood risks are a known and accepted hassle for most Houstonians. Most, however, do not know that dry floodproofing solutions exist, are proven, and affordable. If you are just joining us in this #HoustonStrong series, be sure to read the earlier entries for context. Here, we will analyze what the most common flood risks are. And then we will discuss how dry floodproofing, and more specifically, how FloodSafe USA solves those problems. As mentioned in our last entry, we highly recommend an assessment from a FloodSafe USA professional to determine the qualifications and flood risks of your home or place of business. FloodSafe USA can prepare a custom flood prevention plan and estimate to address your specific needs, once assessed.
Doorways, Windows, and Plumbing
These are the most obvious flood risks, are they not? Everyone knows water comes in through doorways and window openings. And most know that sewage can back up into your home through your plumbing. Any plumber can install a backflow prevention device so that doesn’t happen. This is an easy fix, so contact your plumber today. Doorways can be protected with any number of do-it-yourself techniques, including sandbagging. This can be a hassle and not always successful, especially if you didn’t have sufficient time to prepare. Flood Doors are the best solution for flooding because they perform as a normal door should, and are automatic. This means no preparation is necessary prior to a flood event — just make sure the door is closed. Active barriers are another option, but again, they require proper setup prior to a flood event to prevent excessive water intrusion. These products will be compared in detail in our next blog entry. Window openings can either be elevated or you can replace your windows with Flood Windows.
Most homes constructed in areas where basements are uncommon, utilize wood-frame construction. Typically, such homes are constructed on a concrete slab-on-grade foundation and the wall and roof structures are then framed on top of the slab using conventional lumber. The 2 x 4 or 2 x 6 wall framing is enclosed externally with an insulated wall sheathing material and insulation fills the gap in between the vertical wall studs on the inside. A variety of external substrate materials may be used to provide the architectural exterior finish to the walls (brick/stone veneer, stucco, sidings of various types). Skip down to the substrate material that exists on your home for more information.
Brick/Stone Masonry Veneer
A masonry veneer substrate allows for a 1- 1 ½” built-in airspace between the backside of the masonry and the face of the wall sheathing material that covers the wood framing. This feature
creates a built-in wall cavity. Weep holes located at the base of the masonry wall every four feet, provide for air circulation and drainage of any excess moisture that may penetrate through the porous masonry surface during heavy rains and typical lawn irrigation. This design feature in masonry veneer walls prevents mold growth within the inner wall cavity by allowing for drainage of excess moisture and the drying effect of continuous air circulation. Weep holes are the prime targets for rising flood waters accessing the wall cavity and passing through the exterior walls, ultimately gaining entrance into the interior living space of a home.
It is a common observance to see weep holes sealed shut by zealous do-it-yourself homeowners, using spray foam or some other sealant products to accomplish the sealing task. While this prevents a major source of water intrusion into the home during a rare flood, it provides a breeding ground for mold growth 24/7, which can cause multiple health concerns for the entire family. Weep holes should never be eliminated from an exterior masonry wall.
Deteriorating concrete and masonry grout at the exterior base-joint – the joint created by the separation of the masonry from the concrete foundation, is also an area of entry for flood waters through the exterior walls.
Brick and natural stone products that are used in exterior substrate applications on homes and commercial buildings are typically very porous, and can allow moisture penetration under extreme conditions, such as occur in a normal flood. Deteriorating grout between the individual bricks and stones is also a critical factor.
Brick/Stone Masonry Veneer Solutions
FloodSafe USA provides comprehensive flood-proofing for masonry veneer wood-framed walls using various proven design methods and state-of-the-art materials to seal the walls water tight to a U.S. Army Corp of Engineers restricted height of three feet above the concrete foundation. Read our previous entry on Dry Floodproofing Qualifications for more on this height restriction.
Our process does not alter the exterior appearance of the masonry wall, and all work is performed from the exterior so no inconvenience is experienced by the homeowner.
All thru-wall penetrations (ie: electrical apparatus, water faucets, vents, refrigerant lines, etc.) must be elevated above the flood zone or properly sealed water tight. (Interior building access may be required for these procedures).
With exterior walls properly protected from rising flood waters, it is much easier to provide other temporary measures to seal doors and low window sills prior to a major flood event (sand bags or flood shields) if prior notice of the storm is given by authorities. The installation of FloodSafe USA Flood Doors and Flood Windows provides for a comprehensively sealed home or commercial building without prior preparation requirements to the flood event.
A wood-framed wall with an exterior stucco substrate can have the same characteristics as the previously mentioned brick/stone masonry veneer substrate. The metal lath that the stucco cement adheres to can either be directly attached to the internal wall sheathing installed to the surface of the wood studs, disallowing air circulation within the interior of the wall assembly, or it can be installed to allow a cavity air space between the stucco and the sheathing, such as in a masonry veneer application. In veneer applications, a narrow and concealed vent, called a weep screed, runs along the bottom of the stucco veneer around the entire perimeter of the wall. Similar to masonry veneer, the weep screed allows water intrusion in flood conditions. The wall-to-foundation base joint is also a source of water intrusion, whether an airspace exists or not.
The flood-proofing solutions for the two stucco installations mentioned above are different from one another, with options as follows:
A decorative stucco molding strip, containing a new concealed continuous vent, may be installed at the top of the designated flood zone, again not to exceed three feet above the foundation level for wood-frame structures. This will allow for air-circulation within the wall cavity space. FloodSafe USA base-joint sealant procedures will be applied continuously across the bottom of the stucco-to-foundation joint to seal-off water intrusion in this critical location. Wall sealant materials applied to the stucco surface to the height of the newly installed decorative molding strip will seal the wall from rising flood waters. Conditions may require another decorative stucco trim piece across the bottom of the wall to conceal the base-joint sealant conditions. Finish painting up to the newly installed decorative stucco strip will cover any slight abnormalities in texture or color resultant from the sealant application.
The procedure for non-veneer stucco flood-proofing is the same, without provision for the installation of a continuous vent at the mid-level decorative strip.
The results in both stucco sealant applications is a tightly sealed lower wall section that prevents water intrusion through the exterior wall into the interior living space. Again, temporarily sealing door openings and lower window sills in the event of an upcoming storm with flood capabilities, may be accomplished with sand bags or the use of removable flood shields. The installation of FloodSafe USA Flood Doors and Flood Windows provides for a comprehensively sealed home or commercial building without prior preparation requirements to the flood event.
Manufactured Wall Siding Material
There are a multitude of various manufactured wall siding materials on the market today. Wall siding materials are attached directly to the wall sheathing that is surface applied to the wood stud framing. Therefore, no air cavity exists with this type of substrate. The flood risks involved with this type of siding are numerous: plank joints, seems, fasteners, and as above, the base joint. Where the siding overlaps the concrete foundation at the bottom of the wall, there is a wide open gap for water intrusion.
Manufactured Wall Siding Material Solutions
Fortunately, most manufactured wall siding materials are conducive to FloodSafe USA floodproofing procedures. Vinyl and metal siding materials are not compatible, and floodproofing procedures must be applied beneath these substrate materials. Otherwise, floodproofing procedures are applied directly to the substrate material as follows.
All surface joints in between siding sheets or planks must be thoroughly sealed. All fasteners must likewise be sealed over in the sealant process. As in the non-veneer stucco process previously addressed, the base-joint — where the siding overlaps the concrete foundation at the bottom of the wall, must be thoroughly sealed. Sealant failure in any of these prescribed areas will allow seepage of flood waters into the interior living space of the home.
Solid coatings utilized in the sealant of siding materials may be tinted to match existing siding located above the flood zone, or finish painted after the sealant process is completed.
The result of sealant applications is a tightly sealed lower wall section that prevents water intrusion through the exterior wall into the interior living space. Again, temporarily sealing door openings and lower window sills in the event of an upcoming storm with flood capabilities, may be accomplished with sand bags or the use of removable flood shields. The installation of FloodSafe USA Flood Doors and Flood Windows provides for a comprehensively sealed home or commercial building without prior preparation requirements for the flood event.
Never Flood Again!
That is the FloodSafe USA motto. If you are ready to invest in dry floodproofing today, Contact us to schedule your home assessment. Coming up, we will compare door products, show you average pricing for FloodSafe USA solutions, and talk about Federal funding and insurance reimbursement available for all types of floodproofing. You can follow this series and more on Facebook, LinkedIn, or visit our website: www.FloodSafeUSA.com.