The Florida Building Code requires window and door flashing to prevent moisture from entering the walls. It is our experience that often, by the time flashing problems are discovered the wall system has already sustained some type of damage. Most often once discovered, damage has occurred and remedial measures are required. There are of course detection methods such as IR photography which allow earlier detection but once discovered the only solutions are deconstruction and reconstruction. It is impossible to over state the importance of properly installed flashing to protect the integrity of the building envelope.

The Florida Building Code addresses flashing as:

1405.3 Flashing. Flashing shall be installed in such a manner so as to prevent moisture from entering the wall or to redirect it to the exterior. Flashing shall be installed at the perimeters of exterior door and window assemblies, penetrations and terminations of exterior wall assemblies, exterior wall intersections with roofs, chimneys, porches, decks, balconies and similar projections and at built-in gutters and similar locations where moisture could enter the wall. Flashing with projecting flanges shall be installed on both sides and the ends of copings, under sills and continuously above projecting trim.

The Florida Building Code addresses flashing as:

R703.8 Flashing. Approved corrosion-resistant flashing shall be applied shingle-fashion in such a manner to prevent entry of water into the wall cavity or penetration of water to the building structural framing components. The flashing shall extend to the surface of the exterior wall finish. Approved corrosion-resistant flashings shall be installed at all of the following locations:

1. Exterior window and door openings. Flashing at exterior window and door openings shall extend to the surface of the exterior wall finish or to the water-resistive barrier for subsequent drainage.
2. At the intersection of chimneys or other masonry construction with frame or stucco walls, with projecting lips on both sides under stucco copings.
3. Under and at the ends of masonry, wood or metal copings and sills.
4. Continuously above all projecting wood trim.
5. Where exterior porches, decks or stairs attach to a wall or floor assembly of wood-frame construction.
6. At wall and roof intersections.
7. At built-in gutters.

In most cases the flashing is required to conduct the water back to the surface of the exterior wall finish, however when flashing around a window or door in residential construction you are allowed to flash to the water resistive barrier instead of the exterior surface. This allows the Residential Designer more flexibility with veneer finishes, but it also complicates the complexity of verifying the existence and function of the flashings. Too often once the flashing is covered by the wall assembly it is a case of out of site and out of mind.

Neither the requirement for flashing material nor the installation protocol are often included in the plan set, but if flashing is to attach to the building wrap before the exterior veneer is installed the earliest possible decision of who (which sub-trade), will accomplish this becomes extremely important and the details for how this is to be accomplished should not be left to chance. The importance of properly integrating the Flashing and the water resisting barrier in residential wall systems cannot be overstressed and is often the ounce of prevention that will eliminate a multitude of problems.

If you have any questions regarding these or other code provisions, please contact Gary Pailthorp, PE, CBO, CFM at gpailthorp@brackenengineering.com.

In late September, a letter was issued by the Secretary or the Florida Department of Business & Professional Regulation (DBPR) to notify stakeholders that Senate Bill 2234, “relating to home inspections and mold-related services” will go into effect on July 1, 2010. The DBPR is moving forward to implement the new law and held meetings in September and October to solicit input from stakeholders from around the state. The implementation of this new law will affect the regulation and licensure of those who perform home inspections mold-related services in the State of Florida. Currently, home inspectors and mold-related professionals are not required to be licensed by the state.

For more information about the meetings and what was presented, go to:
Home Inspections
http://www.myfloridalicense.com/dbpr/pro/homein/index.html
Mold-related services
http://www.myfloridalicense.com/dbpr/pro/mold/index.html