HomeMy WebLinkAboutBuilding Miscellaneous 2013-3-25 lrli •• •. .. • . ••
LI .• :stPEilimei ieL6 THE losh,. . . VI BUILDING EUGENE
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•Excerpt from 2011 Oregon Residential Specialty Code Section R703,€xterior Clvtrir>g`• • ••••• ••• • ••• •
RZ(13.1.1 Exterior Wall Envelope. To promote building durability, the exterior wall envelope shall
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•••• be installed ir,aft-tanner that water that enters the assembly can drain to the exterior.The envelope
.sllaliconsist•of an exterior veneer, a water-resistive barrier as required: R X032, eminimum V8.
inch space•b true:en the water-resistive barrier and the exterior veneer,2 id inteaated flasl:ngs 1,5
• �•• . required in R703.1.The required space shall be formed by the use of aflyfion-eorrddible furring•
•• ••strip , drainage mat or drainage board.The envelope shall provide proper integration of flashings
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••••• ••with the wettr-�asistive barrier, the space provided and the exterior veneer.These components, in
•••• ' clAjunction,Mll provide a means of draining water that enters the assembly to the exterior.
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.. .• •• •Excepttd'hs:• •
• 1. A apace.is not required where the exterior veneer is installed over a water-resistive barrier
•• complying with section R703.2 which is manufactured in a manner to enhance drainage and•
meets the 75%drainage efficiency requirement of ASTM E2273 or other recognized
national standards.
2. A space is not required where window sills are equipped with pan flashings which drain to
the exterior surface of the veneer in a through wall fashion.All pan flashings shall be
detailed within the construction documents and shall be of either a self-adhering
membrane complying with AAMA 711-07 or of an approved corrosion-resistant material or
a combination thereof.Self-adhering membranes extending to the exterior surface of the
veneer shall be concealed with trims or other measures to protect from sunlight.
3. A space is not required where the exterior veneer is manufactured in a manner to enhance
drainage and meets the 75%drainage efficiency requirements of ASTM E2273 or other
recognized national standards and is installed over a water resistive barrier complying with
section R703.2.
4. A space is not required where the exterior veneer is matching an existing exterior finish as
in additions, alterations, or repairs.
5. A water-resistant exterior wall envelope shall not be required over concrete or masonry
walls designed in accordance with Chapter 6 and flashed according to section R703.7 or
R703.8.
6. Compliance with the requirements for a means of drainage,and the requirements of
Section R703.2 and Section R703.8,shall not be required for an exterior wall envelope that
has been demonstrated to resist wind-driven rain through testing of the exterior wall
envelope, including joints, penetrations and intersections with dissimilar materials, in
accordance with ASTM E 331 under the following conditions:
6.1. Exterior wall envelope test assemblies shall include at least one opening, one control
joint, one wall/eave interface and one wall sill.All tested openings and penetrations
shall be representative of the intended end-use configuration.
6.2. Exterior wall envelope test assemblies shall be at least 4 feet by 8 feet in size.
6.3. Exterior wall assemblies shall be tested at a minimum differential pressure of 6.24
pounds per square foot.
6.4. Exterior wall envelope assemblies shall be subjected to a minimum test exposure
duration of 2 hours.
The exterior wall envelope design shall be considered to resist wind-driven rain where the
results of the testing indicate that water did not penetrate: control joints in the exterior
wall envelope;joints at the perimeter of openings penetration;or intersections of
terminations with dissimilar materials.