3/7/2016. Who is J.M. Huber Corporation? Privately held by founding family for more than 125 years 80 locations in 28 countries About 5,000 employees

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1 CA OR WA NV ID AZ UT MT WY NM CO ND SD NE TX KS OK MN IA MO AR LA WI IL MS TN IN MI AL KY O GA WV SC FL PA NC VA NY VT DE MD MA NJ ME CT N RI 3/7/2016 J.M. uber Corporation, A Global Organization Who is J.M. uber Corporation? Privately held by founding family for more than 125 years 80 locations in 28 countries About 5,000 employees uber Engineered Woods LLC Leader in delivering high quality, branded and innovative engineered wood solutions Five manufacturing locations throughout the U.S. Air, Water & Moisture Management in Light Commercial Building Envelopes uber Engineered Woods AIA CES For Credit, 1-SW Learning Unit (LU) (EW502) uber Engineered Woods LLC, is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non- AIA members are available upon request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation. 1

2 Copyright Materials This presentation is protected by US and International copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker is prohibited. UBER ENGINEERED WOODS, LLC. Learning Objectives To identify three different ways how liquid water, water vapor and air differ in both their physical properties and how they behave Participants will understand and identify the four D s of water management and how they effect the building envelope Explore the physics of air and moisture movement through the building enclosure, and give an example of solar driven moisture To identify alternative moisture and air barrier design solutions Proper Installation of two WRB systems and roofing underlayment systems Water Management In Order of Importance 1.) Water 2.) Air 3.) Vapor 2

3 Definitions: Liquid Water vs. Water Vapor Water vapor: molecule running free Liquid water: attached molecules Behavior Water: concentration gradient, wicking, gravity Vapor: concentration gradient (more to less), temperature gradient (hot to cold) Durability Issues (Risk factor) ighest risk Liquid water Moderate risk Air carrying water vapor moves with air Lowest risk Vapor moves through the air TE FOUR D s OF WATER & AIR MANAGMENT 1. Deflection 2. Drainage 3. Drying 4. Durability Liquid Water Control Strategies Deflection Deflection should help prevent liquid deposition not Increase the risk Roof overhangs and peaked roofs --Overhangs and peaked roofs can reduce rain deposition by 50% Drip edges -- elp deflect water away from the structure Splash height from ground 3

4 DEFLECTION?? DEFLECTION?? Liquid Water Control Strategies Cont d Drainage *Recommended ¼ gap / 1 for brick *Recommended by Building Science Corporation 4

5 Liquid Water Control Strategies Drainage Screen or cladding Drainage gap (often a clear air space) Drainage plane (water repellent plane) Flashing at areas of interruption and at base Drain holes Drainage Mat Drainage mats are also available as a method to create a clear, drainable space 5

6 Liquid Water Control Strategies Cont d Drying 1. Evaporation from surfaces 2. Vapor movement by diffusion or air leakage 3. Drainage by gravity 4. Convection (air movement) When the wetting rate exceeds the drying rate is when problems can accrue Water Management Ways to Improve Water Management Deflection Methods Sloped roofs, roof overhangs, drip edges Drainage Methods Uninterrupted air gap Effective water resistive barrier Proper flashing Proper integration of materials (i.e. joints) Drying Methods Utilize air gaps (air movement) Use products that don t absorb water Avoid products that let liquid water readily pass through them ( remember the 4 D s ) 6

7 Air Leakage and Thermal Performance Air Tightness Building Envelope: A System of Many Building envelope air tightness Assemblies, windows, doors, walls Penetrations Interfaces between components Channel Air Diffuse Orifice Leakage Flow 7

8 Common Air Leakage Points People, Planet, and Profit Climate Change Thermal Comfort Energy Efficiency $ Air Quality (interior and exterior) Moisture Damage VAC Sizing Convective Loops Convective Loops? **Image derived from Building Science Corporation Impact on Effective R-Value Installed R-Value ( F x ft.² x h/btu) Loss of Effective R-Value* due to wind washing 100% With Air Barrier 80% 60% 40% 20% 0% x x W/0 Air Barrier *fiberglass insulation Wind speed, mph *Source: Impact of airflow on the thermal performance of various residential wall systems utilizing a calibrated hot box, David C. Jones Thermal Envelope VI/eat Transfer in Walls II Principles (p ) 8

9 Air Barrier System Air Barriers prevent air flow through the wall. Effective ABS: (1) Continuous (2) Durable (3) Strength (4) Impermeable (5) Stiffness **Tape adhesion Continuity of air barrier is important! Blower Door Test Performance Verification Blower Door Tests Measures the air infiltration rate of a building. Powerful fan mounted to an exterior door frame lowers the interior air pressure by pulling air out of the house. Air leaking into the house from outside can be detected using a smoke pencil. 9

10 Thermal Imaging Thermal (infrared) image showing air leakage at the bottom of a wall and through an electrical outlet. Can be taken with blower door operating. Effective ABS? Breaks in the Envelope 10

11 WATS WRONG?? Ways to Improve Air Tightness Caulk and foam gaps and seams Spray foam insulation Building wraps (with all seams, edges and details sealed!) Spray-on or peel n stick air barriers Taped wall sheathing panels Vapor Management 11

12 Water Vapor Transported by Air Currents ΔP Air Barrier Air contains Water vapors Vapor Movement By Air Currents Moisture contributed through air leakage vs. vapor diffusion Order of Importance Water Air Vapor Water leakage rots walls, not water vapor. * *University of Massachusettes, Building Materials and Wood Technology, ousewraps, Felt Paper and Weather Penetration Barriers, Paul Fisette, Vapor retarders retard moisture due to diffusion, while most moisture enters walls either through fluid capillary action or as water vapor through air leaks. Point for: Water entry Air entry Vapor entry 12

13 Water Vapor Transported by Diffusion --From igher to Lower concentration --This is where perm ratings are applicable. + igh Air Pressure - Low Air Pressure Water-Resistive Barrier Permeance is a property that defines the ease at which water molecules diffuse through a material. Permeance of a material is measured in perms. The lower the perm rating the more resistance to vapor transmission. 13

14 Water-Resistive Barrier So, which perm rating is the right one? Balance: A water resistive barrier should have enough permeability to allow the wall system to adequately dry out but not so much permeability that excess water vapor is allowed into the system from the outside. 10 Perm Rating 20 Solar Vapor Drive Inward vapor movement due to solar radiation Reservoir cladding like brick 1. It rains Brick absorbs water umidity is higher outside (vs. inside) 2. The sun comes out Temperature of brick raises 3. The air condition is on Inside condition is cooler and less humid 4. Vapor movement From warm to cool and more to less Interior gypsum at cooler temperature *From Building Science Corporation: Reservoir Claddings igh perm waterresistive barrier 14

15 Water barrier, air barrier, vapor barrier Function of water resistive barrier: keep water out. Function of air barrier: keep air out. Function of vapor barrier: keep vapor out. So, why the confusion? Some products function as one, two or all three Overemphasis on perm ratings to-date Lack of understanding: It is intuitive to think breathable is associated with air movement and not vapor. Pitfalls of Today s Control Methods Water-Resistive Barrier Proper installation is CRITICAL Water must remain outside of the protective wrap * ousewrap must be installed properly or it could be more detrimental than beneficial. ** *University of Massachusettes, Building Materials and Wood Technology, Leaky ousewraps, Paul Fisette, **FEMA 499, ome Builder s Guide to Coastal Construction, Technical Fact Sheet No. 23, ousewrap, August

16 Pitfalls by Product Category Roll or Spray-on Products Can be difficult to achieve mil consistency Inefficiency due to multiple layers of coating Slower installation time due to cure time required Grade D Building Paper Does not function well as air barrier/retarder Can tear easily Can be difficult to install when windy ousewrap All seams, holes, and penetrations must be sealed to function as an air barrier. Can tear if left exposed Poor adhesion of flashing material and tape Difficult to install on windy days Complex and ever-changing flashing, repair and installation details Potential Failures 16

17 Stone and Stucco Second layer First layer Code Requires 2 layers Grade D paper (or a layer WRB + intervening layer) over wood-based sheathing 17

18 Building Wraps and Paper Macro-porous Perforated Dilemma? Macro-holes in film provide vapor permeance but sacrifice air and water resistance Micro-porous Perforated Dilemma? Abrasion / tear resistance Asphalt Papers and Felts Dilemma? Absorbs moisture, low durability, less pliable 18

19 Roof Systems Components Wall Roof Exterior Finish Brick, vinyl, fibercement Shingles, tile, cedar shakes Control Layer & Drainage Gap Building wrap, roll-on Felt Structure Wall studs Roof rafters, truss system Distribution Plumbing, electrical Plumbing, VAC Interior Finish Drywall Drywall Physical concepts apply to both systems because they serve the similar functions and are made up of similar layers. NAB Construction Quality Survey Subject: ROOFING Question: What installation/application-related problems are you seeing? Top responses % of Total Inadequate nailing 33% Absence or damaged felt 23% Exposed nails 20% Absence of drip edge 9% Poor flashing details 7% Dried In Defined: aving roofing underlayment installed on the roof Electrical, Plumbing and VAC may begin rough installation once the building is dried in Most trades wait until finished roof covering is installed to begin rough installation. If the roofing felt blows off, the building is NOT dried in. Roofing delays can delay other trades. 19

20 Dried In This building is NOT dried in. Roofing Underlayment Pitfalls 15# Felt Can tear easily if left exposed. If shingles are lost during a windstorm, so is the felt leaving the structure susceptible to water damage. Alternative Solutions 20

21 Extruded Polystyrene Sheathing Lightweight. Not a structural panel. Vapor permeance < 3 No nail holding strength. as insulating properties. Some types can be installed as a WRB and air retarder with special detailing. Can be easily punctured. Seams must be taped Roll- or Sprayed-On WRB Won t rip/tear Temperature restrictions for installation Consistency difficult to achieve Cure time required Different installation instructions for different substrates Surface must be clean before application Permeance 6-17 OSB Panel with Integrated Moisture Barrier Structural panel like OSB and plywood Durable-Moisture barrier and OSB are manufactured as one product with the moisture barrier being an integral part of the OSB. Wall system is code recognized as a WRB and Type 1 air barrier. Roof system is code recognized as a roofing underlayment. Panel seams must be taped with system tape. 21

22 OSB Wall Panel with Integrated Moisture Barrier System Benefits: Vapor Permeable-Moisture Barrier is perms. Windy weather does not impede tape application. Water cannot become trapped between the OSB and the moisture barrier. System tape can be used as flashing tape. Less chance for flashing installation errors 30-year warranty OSB Roof Panel with Integrated Moisture Barrier System Benefits: Eliminates rework After roof system is taped, building is dried in and mechanical contractors can begin rough-in. Can be exposed for 180-days Unique and clean appearance 30-year warranty OSB Panel with Integrated Moisture Barrier Limitations Only Type V construction and construction permitted under IRC and IBC. Roof slopes must be 2:12 slope min. Not approved for adhesively-attached EIF Systems 22

23 Installation Weather Resistive Barrier (WRB) on Two Systems 1. ouse Wrap as WRB 2. Structural Panel with Integrated WRB Roofing Underlayment on Two Systems 1. Felt Paper as Underlayment 2. Structural Panel with Integrated Underlayment Demonstrations - ow to Install WRB - ow to Detail Windows - ow to Detail Penetrations - Using Continuous Insulation in conjunction with WRB - ow to install underlayment on roof OSB Panel with Integrated Moisture Barrier Specification Tools Extensive library of installation details available AutoCAD and pdf CSI-formatted specifications TANK YOU FOR PARTICIPATING This Concludes the uber Engineered Woods LLC, AIA/CES, Continuing Education Program (1-SW Learning Unit), Air, Water & Moisture Management in Light Commercial Building Envelopes 23

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