Pre-WWII Buildings. Performance? Environmental Separation. Mold, Rot, Corrosion, Decay, Recladding

Size: px
Start display at page:

Download "Pre-WWII Buildings. Performance? Environmental Separation. Mold, Rot, Corrosion, Decay, Recladding"

Transcription

1 Pre-WWII Buildings John Straube, Ph.D., P.Eng 2013 Environmental Separation No added insulation (or very little) Heating systems and some natural ventilation No air conditioning No vapor barriers Few explicit air-tightening or draft-stopping details Masonry and old-growth solid timber structures Plaster is the dominant interior finish presented by 11 Mold, Rot, Corrosion, Decay, Recladding Performance? More than on-time, on-budget, to code Safe Healthy Comfortable A growing clamor for. Durable Low-energy Maintainable Modifiable Repairable All delivered reliably, predictably Enclosures No. 12 / Starube buildingscience.com 1 of 23

2 Why High Performance? Green? Changing needs Rising comfort/amenity expectations Control energy / maintenance costs Building Functions Human needs more than shelter (e.g. Location, Shelter, Utility, Comfort & Delight) function of a building: Provide the desired environment for human use and occupancy Durability, Convenience, and Beauty Vitruvius, 70 BC Enclosures No. 15 / Building Components Buildings are made of several large systems Can be grouped in four categories Superstructure Service Systems Fabric Enclosure.com Enclosures No. 16 / Importance of the Enclosure Image People see it! Building problems Often heat, moisture and the enclosure Energy consumption Driven by enclosure performance Durability often less than building Roof yrs, Windows yrs Sealants 5-25 yrs Enclosures No. 17 / Starube buildingscience.com 2 of 23

3 The Enclosure: An Environmental Separator The part of the building that physically separates the interior and exterior environments. Includes all of the parts that make up the wall, window, roof, floor, etc from the innermost to the outermost layer. Sometimes, interior partition also are environmental separators (pools, rinks, etc.) Building Enclosure Components We will cover: roofs, walls, basements/slabs and windows Enclosures No. 18 / Enclosures No. 19 / Enclosure Loadings Loads: Climate / Site The separation function generates loads Load: any event, phenomenon or characteristic that can affect the enclosure Heat, Air, Moisture Fire, Sound UV, Ozone Gravity, impacts, abrasion Insects Etc Enclosures No. 20 / Design for Climate zone Site Seattle Sacramento Miami Minneapolis Edmonton Vancouver Building height, shape, complexity Marcus Vitruvius Pollio These are properly designed, when due regard is had to the country and climate in which they are erected. For the method of building which is suited to Egypt would be very improper in Spain, and that in use in Pontus would be absurd at Rome: so in other parts of the world a style suitable to one climate, would be very unsuitable to another: for one part of the world is under the sun's course, another is distant from it, and another, between the two, is temperate. Enclosures No. 21 / Starube buildingscience.com 3 of 23

4 Canada: Climate Zones Significant heating demand, in lots of places HDD 18C Enclosures No. 23 / Climate Load Modification Evolution Building & Site (overhangs, trees ) Creates microclimate Building Enclosure (walls, windows, roof ) Separates climates Commercial Passive modification Building Environmental Systems (HVAC ) Active modification Use energy to change indoor weather Residential Enclosures No. 24 / Enclosures No. 25 / Starube buildingscience.com 4 of 23

5 Basic Functions of the Enclosure 1. Support Resist and transfer physical forces from inside and out Functional Layers 2. Control Control mass and energy flows 3. Finish Interior and exterior surfaces for people Distribution a building function Enclosures No. 26 / Basic Enclosure Functions Support Resist & transfer physical forces from inside and out Lateral (wind, earthquake) Gravity (snow, dead, use) Rheological (shrink, swell) Impact, wear, abrasion Control Control mass and energy flows Finish Interior and exterior surfaces for people Functional Layers Enclosures No. 27 / Basic Enclosure Functions Other Control Functions... Support Resist & transfer physical forces from inside and out Control Control mass and energy flows Rain (and soil moisture) Drainage plane, capillary break, etc. Air Continuous air barrier Heat Continuous layer of insulation Vapor Balance of wetting/drying Finish Interior and exterior surfaces for people Functional Layers Support Control Fire Penetration Propagation Sound Penetration Reflection Light Diffuse/glare View Finish Functional Layers Enclosures No. 28 / Enclosures No. 29 / Starube buildingscience.com 5 of 23

6 History of Control Functions Older Buildings One layer does everything Newer Building Separate layers,... separate functions Basic Enclosure Functions Support Resist & transfer physical forces from inside and out Control Control mass and energy flows Finish Interior & exterior surfaces for people Color, speculance Pattern, texture Functional Layers Enclosures No. 30 / Enclosures No. 31 / What is the gypsum board for? Finish vs. Control Confusion Distribution A Building Function imposed on enclosure Distribute services or utilities to from through, within, the enclosure, e.g., Power Communication Water (Potable, sewage, etc.) Gas Conditioned air Cold or hot water Enclosures No. 32 / Enclosures No. 33 / Starube buildingscience.com 6 of 23

7 Enclosure Design Principles 1 Design a complete structural load transfer path Structure, windows, ties, etc All loads go to ground Understand site, use, and climate loadings Rain, sun, high rise or low-rise, pool, office, school Continuous rain control plane Control with surface features and detailing Drained, storage, or perfect barrier strategy Continuous plane of air barrier tightness Fastidious attention to detail 3-D Enclosure Design Principles 2 Provide a continuous plane of insulation Ideally separate structure from enclosure Avoid thermal bridges Provide a moisture tolerant design Balance wetting, drying, and storage (matl s, climate) Use appropriate levels of vapour control No cold vapor barriers, allow drying Accommodate movements and tolerances Draw all of the Details! Enclosures No. 34 / Enclosures No. 35 / The Enclosure: Adding the Layers Framed Enclosures: Adding the Layers Structure Structure Air-Rain Barrier Insulation Air Flow Control Insulation Finish Rain Control Finish Enclosures No. 36 / 2008 Enclosures No. 37 / Starube buildingscience.com 7 of 23

8 Design Information older than I am. 1. Air / Rain Barrier 2. Structural Support 3. Rain Shedding 4. Insulation What is a high performance enclosure? High levels of control But, poor continuity limits performance & Poor continuity causes most problems too: E.g. air leakage condensation Rain leakage Surface condensation Cold windows Thus: continuity + high levels of control 38 High Performance No leaks = continuous = no holes 1. Rain 2. Air 3. Thermal.com 41 Starube buildingscience.com 8 of 23

9 Rainscreen or Drained System.com 42.com Enclosures No. 43 /.com Enclosures No. 44 /.com Enclosures No. 45 / Starube buildingscience.com 9 of 23

10 .com Enclosures No. 46 /.com Enclosures No. 47 /.com Enclosures No. 48 /.com Enclosures No. 49 / Starube buildingscience.com 10 of 23

11 .com Enclosures No. 50 /.com Enclosures No. 51 / Enclosures No. 52 / Enclosures No. 53 / Starube buildingscience.com 11 of 23

12 Window Enclosures No. 54 / 2008 Enclosures No. 55 / Enclosure Design: Details Details demand the same approach as the enclosure. Scaled drawings required at - change in plane - change in material - change in trade.com 56/ Starube buildingscience.com 12 of 23

13 Plan Dimensions 58.com Baseplate usually wider than column at the critical base plate.com.com Starube buildingscience.com 13 of 23

14 .com.com Starube buildingscience.com 14 of 23

15 .com 66.com 67.com 68.com 69 Starube buildingscience.com 15 of 23

16 Perfect Wall Asphalt Drainage Plane Air Barrier Rockwool Insulation CMU backup.com 2008 Enclosures No. 71 / The Commercial Steel Frame High Performance wall Enclosures No. 73 / Starube buildingscience.com 16 of 23

17 Perfect Wall on Steel stud Sprayfoam Control Layer Transitions, Continuity, Penetrations Enclosures No. 74 / 2008 Enclosures No. 75 / Attachment Enclosures No. 76 / Enclosures No. 77 / Starube buildingscience.com 17 of 23

18 .com.com The Compromise Wood Frame High R-value wall Enclosures No. 81 / Starube buildingscience.com 18 of 23

19 Discontinuous thermal and air barrier Enclosures No. 82 / Enclosures No. 83 / Wood Framed Furring 2x6 w/r5 exterior is a start 2x4 w/r7.5 for higher interior RH 2x6 w/r10-r15 is likely long-term answer Cladding attachments Insulating on exterior is not a structural challenge unless you use the wrong model Bending does matter, but only at high deflections Increasing ratio of Exterior to Cavity insulation reduces risk and improves performance Starube buildingscience.com 19 of 23

20 Foam sheathing field testing Foam sheathing lab testing 4 x 8 panel, 14 #10 screws 65 1/32 deflection Enclosures No. 88 / Flow through wall. Allows fast drying in both directions Starube buildingscience.com 20 of 23

21 Rockwool 1x3 24 o.c. #10 16 o.c. vertically Result: 20 psf cladding weight with < 2/100 deflection Houses Rain Heat Air has many different enclosure sections /175 Perfect wall variation Except at joints Enclosures No. 93 / Starube buildingscience.com 21 of 23

22 2008 Enclosures No. 94 / Enclosures No. 95 / Metal Panels Furring Commercially available Only fasteners penetrate insulation Starube buildingscience.com 22 of 23

23 Recall: Enclosure Functions Support Resist & transfer physical forces from inside and out Control Control mass and energy flows Rain (and soil moisture) Drainage plane, capillary break, etc. Air Continuous air barrier Heat Continuous layer of insulation Vapor Balance of wetting/drying Finish Interior and exterior surfaces for people Functional Layers 2008 Enclosures No. 98 / Enclosures No. 99 / Starube buildingscience.com 23 of 23