BUILDING ENVELOPE By Sabrina D Ambra

Transcription

1 BUILDING ENVELOPE By Sabrina D Ambra

2 2 OUTLINE Workplan Objectives Chp 6 Building enclosure design: Highlights Structural system Rainscreen system Prescriptive Path Results Design of Wall Design of Roof Remaining Tasks Questions

3 3 WORK PLAN OBJECTIVES Calculation of rain and wind load Choosing cladding type Review of chapter 6 Designing a rain screen Calculation thermal performance Calculating vertical movement (shrinkage and swelling) Designing joint details Understanding space acoustics Highlighting possible points of failure (wetting and drying) Proposing a roof design

4 CHP6 BUILDING ENCLOSURE DESIGN: HIGHLIGHTS Keys to Durability: Prevent excessive moisture accumulation, AND Allow wood to dry 4 Design Requirements Rainscreen strategy Exterior Insulation Air barrier Vapor permeable membranes/finishes required

5 Impacts Location of insulation Details CHP6 BUILDING ENCLOSURE DESIGN: STRUCTURAL SYSTEM 5 Envelope Assembly Post-and-beam with wood-frame infill INFILL: Non-load bearing, light wood frame

6 CHP6 BUILDING ENCLOSURE DESIGN: STRUCTURAL SYSTEM 6 Alternative: Mass Timber (CLT) Wood-frame infill walls: Non-load bearing

7 CHP6 BUILDING ENCLOSURE DESIGN: RAINSCREEN SYSTEM 7 Basic Elements Continuous Water Shedding Surface Cladding Drain holes/gaps all penetrations Airspace Ventilated Cavity (0.2 ACH) Drained to outside Continuous Air WRB layer

8 8 PRESCRIPTIVE PATH RESUTLS North Vancouver: Zone 5 (Table B-2 ASHRAE 90.1 (2010)) HDD 3000 Minimum Effective Assembly R-values NECB 2011: Above Grade, All Construction Types WALL : Km 2 /W ROOF: 5.46 Km 2 /W

9 DESIGN WALL ASSEMBLY: WOOD STUD CAVITY WALL 9 Interior-Insulated (less preferred) Split-Insulated Designed R-value: 3.61 Km 2 /W Designed R-value: 4.62 Km 2 /W

10 Interior Insulated (less preferred) R-value: 3.61 Km 2 /W Thickness: 190 mm PRELIMINARY WUFI- WALL OPTION 1: INTERIOR INSULATED 10 Exterior-to-Interior Cladding (composite wood siding), 10.5 mm Vertical Strapping (?) Air Layer, 20mm Self-adhered Weather Resistive Barrier (sd=0.1), 0.1mm Blueskin VP TM adhesive-primers Exterior Gypsum Board, 13 mm Low density Glass Fibre Batt Insulation, 140 mm Interior Gypsum Board, 12.5mm

11 11 WUFI SIMULATION RESULT: INTERIOR INSULATED STUD WALL

12 PRELIMINARY WUFI- WALL OPTION 2: SPLIT INSULATED 12 Split Insulated R-value: 4.62 Km 2 /W Thickness: 210 mm Exterior-to-Interior Cladding (composite wood siding), 10.5 mm Vertical Strapping (?) Air Layer, 20mm Extruded Polystyrene Insulation (taped/sealed), 25.4 mm Self-adhered Weather Resistive Barrier (sd=0.1), 0.1mm Blueskin VP TM adhesive-primers Exterior Gypsum Board, 13 mm Low density Glass Fibre Batt Insulation, 140 mm Interior Gypsum Board, 12.5mm

13 13 WUFI SIMULATION RESULT: SPLIT-INSULATED STUD WALL

14 CLADDING ATTACHMENT OPTIONS: WOOD STUD WALL 14 Semi-rigid mineral-fibre insulation 2X6 Wood Framing w/ Batt Insulation SELECTED Rigid mineral-fibre insulation 2X6 Wood Framing w/ Batt Insulation

15 DESIGN WALL ASSEMBLY: MASS-TIMBER (CLT) 15 Exterior-Insulated

16 DESIGN WALL ASSEMBLY: CLT WALL 16 CLT, Exterior Insulation R-value: 3.55 Km 2 /W Thickness: 170 mm Exterior-to-Interior Cladding (composite wood siding), 10.5 mm Vertical Strapping (?) Air Layer, 20mm Extruded Polystyrene Insulation, 70 mm Self-adhered Weather Resistive Barrier (sd=0.1), 0.1mm Blueskin VP TM adhesive-primers CLT wall (4 layers) (15 mm/layer), 60 mm Interior Gypsum Board, 12.5mm

17 17 WUFI SIMULATION RESULT: CLT WALL

18 CLADDING ATTACHMENT OPTION: CLT PANEL 18 Semi-rigid mineralfibre insulation CLT panel

19 19 ROOF

20 20 ROOF OPTIONS

21 DESIGN ROOF ASSEMBLY: INVERTED/PROTECTED MEMBRANE 21 Low-slope, Exterior-Insulated

22 Low-slope, Exterior insulated R-value: 5.5 Km 2 /W Thickness: 230 mm DESIGN ROOF ASSEMBLY: INVERTED/PROTECTED MEMBRANE 22 Exterior-to-Interior Ballast (Expanded Clay aggregrate), 25 mm Filter Felt laminated polypropylene membrane, Exterior Gypsum Board, 13 mm Extruded Polystyrene Insulation (2 layers) (60mm/layer) WRB: Asphalt Impregnated Paper (60 min), 0.3 mm OR Vapour Barrier (sd = 1500) CLT deck (12 ply), 60 mm Interior Gypsum Board, 12.5mm

23 23 WUFI SIMULATION RESULT: INVERTED/PROTECTED MEMBRANE

24 DESIGN ROOF ASSEMBLY: GREEN ROOF 24 Green Roof, Extensive R-value: 5.46 Km 2 /W Thickness: 370 mm Exterior-to-Interior Soil, 150 mm PE membrane (sd = 87m), 0.2 mm Filter Felt laminated polypropylene membrane, Exterior Gypsum Board, 13 mm Extruded Polystyrene Insulation (2 layers) (60mm/layer) Vapour Barrier (sd = 1500) CLT deck (12 ply), 60 mm Interior Gypsum Board, 12.5mm

25 25 WUFI SIMULATION RESULT: GREEN ROOF

26 LOCATION & WEATHER STATIONS 26

27 LOCATION & WEATHER STATIONS 27

28 28 REMAINING TASKS Update Wall & Roof Assemblies (Feedback) Selection of Cladding (Non-combustible) Selection of Strapping for cladding Rerun Hygrothermal Simulations (WUFI) Update Climate File Design of roof drainage Design joint details for tall wood buildings Details for vertical movement due to shrinkage and swelling Complete Wind-Driven-Rain analysis Overhang design

29 29

30 30 DISCUSSION & QUESTIONS Cladding: Combustible: Composite Wood-Siding Non-combustible: Stucco, Concrete board, vinyl siding, etc? Attachments: Strapping? Verticle strips of treated wood OR Light-gauge metal girts? Wall Assembly: Interior-insulated? OR Split-insulated Wood Stud wall? OR CLT wall? Roof Assembly: Type of Deck Green roof = OK for a portion of roof? Inverted/Protected Membrane for main roof = OK? Tapered Insulation? OR Tapered Structure?

31 31 REFERENCES 1. Blocken, B., Dezsö, G., van Beeck, J., & Carmeliet, J. (2010). Comparison of calculation models for wind-driven rain deposition on building facades. Atmospheric Environment, 44(14), doi: 2. Plescia, M. S., Eng, P., Lonescu, D., Simpson, M. B., Ge, H., & Krpan, R. Wind-driven Rain Study in the Coastal Climate of British Columbia. 3. Technical Guide for the Design and Construction of Tall Wood Buildings in Canada 4. Guide for Designing Energy-Efficient Building Enclosures: For Wood-Frame Multi-Unit Residential Buildings 5. The Performance of Rainscreen Walls in Coastal British Columbia, Graham Finch 6. ASHRAE NECB Tall Wood 9. CLT Handbook Canadian Edition 10. CLT Handbook U.S. Edition

32 32 THANK YOU FOR LISTENING! ALMOST LUNCH TIME!