Stucco and Windows on Wood Frame Construction. Maintaining the Water-shedding Barrier

Transcription

1 Stucco and Windows on Wood Frame Construction Maintaining the Water-shedding Barrier

2 What is the Water-shedding Barrier? Figure 2-5 Critical barriers of the typical window-wall interface, RESIDENTIAL WINDOW INSTALLATION OPTIONS FOR HURRICANE-PRONE REGIONS, Cory Thomas Salzano

3 Maintaining the Water-shedding Barrier Two primary issues How to seal the stucco to the window? This is pretty straight forward Everyone tends to agree with the standards (exception: backer rod, bond break tape, ASTM C 1163) How should the connection between stucco veneer and windows be achieved? No consistency in opinion No consistency between standards and the actual methods being used in the field

4 Maintaining the Water-shedding Barrier What do the standards say? What do engineered systems require? What do window manufacturers say? What are contractors doing?

5 The Standards The 2007 FBC and FBC-R make reference to ASTM C for lath installation The 2007 FBC-R makes reference to ASTM E for window installation R Windows and doors shall be installed in accordance with ASTM E 2112 or in accordance with the manufacturer s installation instruction.

6 ASTM C Casing Beads Nonload-bearing members shall be isolated from load-bearing members, and all penetrating elements, with casing beads or other suitable means, to avoid transfer of structural loads, and to separate from dissimilar materials.

7 ASTM E Any chemicals, petroleum-based releasing agents or protective coatings made of petroleum or corrosive materials that are used in the installation of interior finishes or exterior cementitious products such as stucco or EIFS, shall not be applied to any portion of the fenestration product.

8 Engineered Systems: Surewall Stucco System Captured from:

9 Engineered Systems: Master Wall, Inc Detail Captured from:

10 General Aluminum s Installation Instructions Captured from:

11 MI Windows Installation Instructions Aluminum windows (vinyl windows similar) 11. Allow a ¼ gap between the exterior cladding, siding, brick, stucco or stone and the window frame on all sides, except vinyl j- channel. The gap (expansion joint) should be filled with correct backer rod, then sealed with a high grade exterior sealant and will need to be maintained. Captured from:

12 Florida Product Approval But, do the installation instructions of windows with 2007 Florida Product Approval provide for non-code compliant stucco installation? Three examples Jordan Florida Extruders General Aluminum

13 FPA Problem: Example 1: Jordan Captured from:

14 FPA Problem: Example 2: Florida Extruders Captured from:

15 FPA Problem: Example 3: General Aluminum Captured from:

16 Florida Product Approval Do the installation instructions of windows with 2007 Florida Product Approval provide for non-code compliant stucco installation? No, stucco by others. Meaning installation of stucco at this location is to be detailed in a code compliant manner by someone other than the window manufacturer. Stucco by others Confuses more than clarifies How important is this detail?

17 Other Thoughts Are the standards worth while? Now that it requires a gap: Will the contractor install the sealant correctly? Will the homeowner renew the sealant correctly? Are there better ways to address where stucco abuts windows (other fenestrations)? Specific details from the designer of record. How is this addressed outside of Florida? No need to reinvent the wheel. Consistency among jurisdictions?