RobShepp wrote:The builder applied decorative stone tiles(roughly 3/4"x4-6"x1-2")
.
.
I am using chapter 44 of the FBC residential to understand that a continuous application of cement shall be used to mount the tiles, but I also thought a base coating of plaster was required underneath the tile? Chapter 7 sends you straight to chapter 44 when located in the HVHZ. I'm using reference R4407.4.6.1.2. This says the support shall be "continuous" across the back of the tile....
Rob,
Not quite understanding the stone tiles - are they tiles of natural stone or manufactured stone? The size you listed is somewhat confusing - are you stating that the stone tiles are in 3/4" wide strips by 4" to 6" long (length varies) by 1/2" thick?
Usually, tiles in strips that narrow (3/4") come on a backing in rectangular strips (such as 6" by 12") or in squares (such as 12" by 12").
The "continuous integral support to the backing" would be that each separate piece was fully adhered to the backing, not that the masonry unit wall was covered with a continuous bed of Portland cement mortar (basically exterior thin set).
In Miami-Dade and Broward counties efforts to overthink the building code as not being "good enough" for them (the HVHZ) they should have just stuck with structural matters and left the rest of the code stand, instead, they exempt out large portions of the code and substitute in "their better code" ... except that, in doing so, they lose what is in the code they exempted out.
This is one example - the Residential Code for the rest of the state requires: (underlining is mine)
- SECTION R703 EXTERIOR COVERING
- - R703.1 General.
- - - Exterior walls shall provide the building with a weather-resistant exterior wall envelope. The exterior wall envelope shall include flashing as described in Section R703.8.
- - - R703.1.1
Water resistance.
- - - - The exterior wall envelope shall be designed and constructed in a manner that prevents the accumulation of water within the wall assembly by providing a water-resistant barrier behind the exterior veneer as required by Section R703.2 and a means of draining to the exterior water that enters the assembly. Protection against condensation in the exterior wall assembly shall be provided in accordance with Section R601.3 of this code.
The HVHZ section only addresses "Water resistance" in relation to: (underlining is mine)
- R4402.12.6.5.2.6 Fiber cement shingle or tile panels.
- - All fiber cement shingles or tiles shall resist a minimum wind uplift resistance as determined by Section R4403 for a roof slope of 9.5 degrees (0.0166 rad) and a roof mean height of 15 ft (4.6 m). All fiber cement shingle or tiles shall be tested in compliance with the following requirements. Wind driven
water resistance in compliance with TAS 100, Physical properties in compliance with TAS 110, TAS 135 and uplift resistance.
That is unless I have missed another reference to "water resistance" in the code.
Most of what is exempted out for the HVHZ and replaced with special HVHZ requirements is not necessarily "better" and does not necessarily address what should be done and ends up being "not as good". Some of the HVHZ requirements are very good and very much needed, but those requirements should really apply across the entire state to every structure.
It was a power struggle (politics) between South Florida and the rest of the state, with South Florida having the greatest centers of population and their own codes before the statewide Florida Building Code - even then, Miami-Dade had its own version of the South Florida Building Code and Broward County had its own version of the South Florida Building Code - they could not even agree with each other back then.