Exterior Insulation and the Cascadia Clip Presenter: Maddy Parrott

Transcription

1 Exterior Insulation and the Cascadia Clip Presenter: Maddy Parrott

2 Introduction Manufacturer of fiberglass construction products Fiberglass windows Fiberglass doors Fiberglass cladding support systems Manufacturing plant located in Langley, BC In operation since 2008 Current client base: BC, Alberta, Yukon, NWT, Washington, Oregon, Alaska Expanding to: Saskatchewan, Manitoba, Ontario, California, other central US States

3 Agenda Conservation why does energy conservation in buildings matter? Building science and the building envelope: Heat flow, U- & R- values, and thermal bridging Energy standards and code requirements Insulation Types, considerations, and performances The Cascadia Clip What it is and how we came up with it Where it s been used What makes Cascadia stand out?

4 Cascadia Windows Ltd Effective Thermal Performance of the Building Enclosure - Exterior Walls Course Number 7 Michael Bousfield & Maddy Parrott June 2017

5 Credit(s) earned on completion of this course will be reported to AIA CES for AIA members. Certificates of Completion for both AIA members and non-aia members are available upon request. 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. This course is registered with AIA CES

6 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. Cascadia Windows Ltd. 2017

7 Course Description Many of today s conventionally insulated wall assemblies fall short of even basic energy code compliance, let alone high performance. Learn what the code prescribed targets are for your region, and what fiberglass cladding support technology can do solve this issue, while saving cost at the same time.

8 Learning Objectives At the end of the this course, participants will be able to: 1) 2) 3) 4) Understand what building types are subject to the ASHRAE 90.1 Thermal Performance standard, and which compliance paths available for the ASHRAE 90.1 standard. Understand the non-linear effect that highly conductive wall components have on the total effective wall R-value. Understand how current conventional wall assemblies compare from a thermal point of view. Identify aspects of exterior wall detailing to target for thermal improvements. Become aware of several conventional and state-of-the-art proprietary approaches that have been used in the past year to solve these issues and reduce costs.

9 Conservation, and the importance of it. Buildings account for 40% of total energy use in Canada and the US Buildings account for up to 30% of emissions Now, more than ever, we must focus on conservation in our buildings

10 The environment is in danger Climate change is a real and pressing problem Policies and funding in place to protect the environment are getting cut Paris Agreement Climate Action Plan Waters of the U.S. Promoting environmentally dangerous energy sources Emphasis on fracking Reviving coal We must individually strive to do better on the demand side

11 The importance of building science in building envelopes

12 Heat Flow Heat flow by waves, does not require a material to move through Blocked by opaque elements Heat flow through a solid material Heat flow through solid materials in contact with one another Heat flow through a fluid material via loops Air is a fluid Stopped by filling air cavities

13 Heat flow conduction Conduction Conductivity Conductance (U-value) Heat flow through solid objects Rate of conductive heat flow Depends on material Aluminum ~160 W/mK Steel ~60 W/mK Stainless Steel ~14 W/mK Fiberglass 0.15 to 0.30 W/mK Wood ~0.10 to 0.15 W/mK Insulation Materials to W/mK Conductivity/thickness Thermal properties of specific materials The lower the U-value, the more thermally effective the material

14 Heat flow U-value and R-value U-value: conductance How well heat moves through an assembly or material The lower the U-value, the better the assembly Efficiency and area-weighted averages require U-values R-value: resistance How well a material or assembly resists heat flow NOMINAL: just the insulation R-value EFFECTIVE: includes all other materials Additive, but that s it 1 R = U 1 U = R

15 Heat flow insulation NOMINAL R-value Heat loss through building envelopes is controlled by insulation: Convection: filling air cavities to prevent convective loops Radiation: opaque material to block sitelines Conduction: insulation is a lowconductivity material Insulation is key for minimizing heat loss through the building envelope

16 Thermal performance Resistances (additive) Interior air film: 0.68 Interior gypsum: 0.45 Batt insulation: 12 Exterior plywood: 0.62 Exterior air film: 0.17 Total R-value: Total U-value = 1/13.92 =

17 Heat flow thermal bridging EFFECTIVE R-value Instead of moving through the efficient insulation, heat takes the path of least resistance: through the highest conductivity materials in an assembly Reduces the overall performance of the building envelope Occurs through the insulation Occurs when insulation is out of plane (basement to wall, etc.) Results in much greater heat loss in envelopes

18 Effect of thermal bridging on thermal performance Through insulation: same as previous example (U , R-13.92) Through studs: Conductivity (k) of 3.5 of douglas fir: k = BTU-in/hr-ft 2 -F U studs = /3.5 = R = 1/ = 4.59 (just studs) Total R = = 6.51 (through studs) Total U wallthroughstuds = 1/6.51 =

19 Effect of thermal bridging on thermal performance With studs at 16 o.c., wall is approx. 12% studs and 88% insulation U total = (0.12)(0.1536) = (0.88)(0.0718) Total U-value = Total R-value = 1/ = Nominal was R-14

20 Effect of thermal bridging on thermal performance R-3.1 R R Insulation only 88% effective

21 Effect of thermal bridging on thermal performance R-3.1 R R-6.6 Insulation only 48% effective Steel studs are even worse The higher conductivity the penetrating material, the worse the effectiveness

22 Energy Codes and Adoption

23 Commercial Energy Codes in the US and Canada Individual building codes require improved energy performance by referencing various energy standards

24 In the US Majority of states have building codes which derive from the International Building Code The International Energy Conservation Code works in conjunction with the IBC The IECC is a mix of direct references to ASHRAE 90.1, or requirements built in which are mostly similar to ASHRAE 90.1 (almost identical for envelope requirements)

25 In Canada National Building Code is adopted and modified provincially Each province can choose to add energy requirements or not Two options in Canada, for the most part: the National Energy Code of Canada for Buildings, or ASHRAE 90.1 (the most common US energy standard)

26 What is ASHRAE 90.1? An energy standard with three ways to achieve compliance: Prescriptive path* Building enclosure trade-off Energy cost budget path *IECC has its own prescriptive path

27 ASHRAE 90.1 and continuous insulation ASHRAE 90.1 stipulates that wall R-values must consider the effect of thermal bridging, to be representative of actual thermal performance (i.e. consider effects of steel studs, girts, clips, slab-edges, balconies, eyebrows etc.). Continuous Insulation (CI): insulation that is continuous across all structural members without thermal bridges other than fasteners and service openings.

28 ASHRAE 90.1 Climate Zone 5

29 ASHRAE 90.1 Thermal Requirements Continuous insulation Requires 100% continuous insulation Penetrated only by fasteners and service openings Does not include final performance target for whole assembly Ways of attaching cladding Screws through insulation EIFS Continuous metal girts Metal clips Fiberglass or composite clips

30 ASHRAE 90.1 Thermal Requirements Maximum assembly U-value Specified based on total wall assembly Based on actual performance of system Can use any materials in any configuration, as long as performance is met Ways of attaching cladding Screws through insulation EIFS Continuous metal girts Metal clips Fiberglass or composite clips

31 Climate Zone 5 Example R 15.6

32 ASHRAE 90.1 above-ground wall requirements Construction Type Type of Building Non-residential Residential Non-residential Residential Non-residential Residential Climate Zone Type of wall Steel-framed Concrete Woodframed (R-8.1) (R-1.72) (R-6.62) (R-8.1) (R-6.62) (R-8.13) (R-11.2) (R-11.2) (R-11.9) (R-8.13) (R-9.62) (R-15.6) (R-9.62) (R-11.1) (R-15.6) (R-11.1) (R-12.5) (R-15.6) (R-15.6) (R-12.5) (R-19.6) (R-14.1) (R-19.6) (R-23.8) (R-14.1) (R-27) (R-19.2) (R-27.8) (R-27.8)

33 Insulation Options, performances, and considerations

34 Fiberglass Batts R-3.5 4/inch Combustible Permeable to liquid water and water vapour (indoor only)

35 Mineral Wool R /inch (stable) Non-combustible Permeable to liquid water and water vapour (outdoor ok)

36 Rigid Insulation XPS EPS Polyisocyanurate R-5/inch (stable) Combustible Impermeable to liquid water and water vapour (outdoor ok) R-4/inch (stable) Combustible Moderately permeable to liquid water and water vapour (outdoor ok) R-5/inch (temperature variable) Combustible Permeable to liquid water and water vapour (indoor/membraned)

37 Sprayfoam Open cell (half pound) Closed cell (two pound) R-3.5 4/inch (stable) Combustible Permeable to water vapour and mostly permeable to liquid water (indoor) Susceptible to UV degradation R-5 6/inch (temperature variable) Combustible Impermeable to water vapour and liquid water (outdoor ok) Susceptible to UV degradation

38 Insulation Comparisons Insulation R-value Non-combustible Moisture Tolerance Vapour Permeance Fiberglass NO Moderate High Mineral Wool 4.2 YES High High XPS 5 NO High Low EPS 4 NO Moderate Low-Mid Polyiso NO Low-Moderate Low Open cell sprayfoam NO Moderate High Closed cell sprayfoam 5 6 NO High Low

39 Insulation challenges for higher performing walls Insulation is critical to the performance of your building, and it s hard and cumbersome to replace- you want to do it once. Many different factors to weigh: Minimize wall thickness Meet or exceed code minimums Minimize costs Create safe and effective walls. You want a system that has all aspects covered

40 Insulation Interior Interior Insulation Thinner overall wall Generally poor ok thermal performance Exterior sheathing is outdoor temperature, at risk for condensation Generally less expensive, but if only interior insulation is used Can reduce usable interior space Requires vapour barrier be inside building envelope

41 Insulation Exterior Exterior Insulation Thicker overall wall, but can help reduce stud size (6 4 ) Best thermal performance (if done correctly) Keeps exterior sheathing at indoor temperature, eliminating condensation risk Extra layer of protection for the building materials from elements Allows for exterior placement of air/vapour barrier best place for both hot and cold climates

42 Insulation Exterior vs. Interior Interior Insulation Thinner overall wall Cheapest if only using interior insulation** Exterior Insulation Best thermal performance Best use of interior space Cheapest option to meet thermal requirements Best location for vapour barrier Best condensation resistance

43 Insulation what about both? Split insulation theoretically allows for the best of both worlds Must ensure it is being designed properly Cannot have two vapour barriers Two on either side means no drying Some insulations are vapour barriers Thermal bridging still a concern

44 Split Insulation condensation We re going to run through some math: Assume: 100ft 2 of wall area Assume conditions: Interior temp 70F (21C) Interior RH 50% Exterior temp 20F (-6C) Use the equation: Q = A T Rvalue Dew point temperature = 51F Heat moving through wall, does not change no matter what part of the wall you look at Can be manipulated to determine temperature at various locations or what R-value given temperatures will occur at

45 Split Insulation 1 exterior mineral wool (R-4.2) R-12.6 effective Dew point temp located at R-4.8 from interior Interior sheathing temperature: 39F Risk of condensing on back of exterior gypsum

46 Split Insulation 2 exterior mineral wool (R-8.4) R-16.8 effective Dew point temp located at R-6.4 from interior Interior sheathing temperature: 47F Risk of condensing on back of exterior gypsum

47 Split Insulation 3 exterior mineral wool (R-12.6) R-21.0 effective Dew point temp located at R-7.9 from interior Interior sheathing temperature: 51.5F Back of exterior gypsum probably ok Days colder than 20F could cause issues Generally pretty sensitive, only 0.5F buffer

48 Split Insulation 4 exterior mineral wool (R- 16.8) R-25.2 effective Dew point temp located at R-9.6 from interior Interior sheathing temperature: 55F Exterior gypsum likely not at risk of condensing You re at an R-25 wall to get the dew point in the right place.

49 4 exterior mineral wool (R-16.8) only R effective Dew point temp located in the exterior insulation Interior sheathing temperature: close to interior temperature, 71F Back of exterior gypsum not at risk of condensing You ve met thermal requirements of all but zone 7 and 8 residential

50 Important things to remember: Weather is important Effect is pronounced with a bigger exterior/interior temperature difference Location of vapour barrier for summer vs. winter months Attachment matters All examples assumed perfect continuous insulation Needed R-15+ exterior insulation to be comfortable The worse your cladding attachment system, the less effective your exterior insulation is (R-16 with some systems might only be R-10 effective)

51 Insulation real life applications for steel studs R-14.7 nominal (3.5 mineral wool) R-5.5 effective

52 Insulation real life applications for steel studs Bypass thick structural stud Attach cladding with thinner gauge continuous vertical girts R-14.7 nominal (3.5 mineral wool) R-7.4 effective

53 Insulation real life applications for steel studs Bypass thick structural studs Attach cladding with horizontal girts R-14.7 nominal (3.5 mineral wool) R-7.8 effective

54 Insulation real life applications for steel studs Intermittent metal clips Continuous metal rail R-14.7 nominal (3.5 mineral wool) R-11.3 effective

55 Insulation real life applications for steel studs Horizontal girts first, with insulation Vertical girts second, with insulation Theory is thermal bridging mitigated for half the insulation R-16.8 nominal (4 mineral wool) R-11.4 effective

56 Insulation real life applications for steel studs Same as last application Add plastic shim between metal girt layers R-16.8 nominal (4 mineral wool) R-13.1 effective

57 The Original Thermal Spacer Where did the clip even come from?

58 Step 1 OK, so we have a conductivity problem Let s use a material with very low conductivity like fiberglass. Backup wall Insulation Fiberglass Z-girt Problem: pull out strength

59 Step 2 Problem: rotation at inner leg Backup wall Backup wall Problem: web/screw interference Main problem: Combustibility Use long screw to attach outer steel directly to stud

60 Step 3 Problem: installation is inconvenient, too many pieces Backup wall Problem: weak furring shape, does not provide drainage cavity Problem: still a continuous member too expensive and poor thermal performance Section Make pieces intermittent

61 Step 4 Backup wall If we use a Z-girt instead Is it done?

62 This concludes The American Institute of Architects Continuing Education Systems Course 2016 BPDL The material contained in this course was researched, assembled, and produced by BPDL and remains its property. Questions or concerns about the content of this course should be directed to the program instructor.

63 The Cascadia Clip Essentially a thermal washer Universal solution: appropriate for almost any type of cladding (up to around 30psf) Approved for non-combustible construction virtually everywhere in North America Can supply just the clips, or the whole system (clips, screws and girts) Engineered for over 75,000 combinations of wall assemblies: The Cascadia Clip Calculator

64 Cascadia Clip Calculator Got it! Demonstration worked as planned Something s up: do this demonstration manually

65 Cascadia Clip Calculator: Inputs Options for steel, concrete, and wood Steel options only allow for 4 steel studs because only the gauge matters for structural considerations Cascadia most often recommends no to batts in the cavity for steel framed, but it is an option Wood pre-selects to yes

66 Cascadia Clip Calculator: Inputs R-4.2/inch is mineral wool; R-6.2/inch is sprayfoam Rigid insulation can be used, we have details, it s just generally more labour Stainless steel screws provide better thermal performance Using only one screw allows for best thermal performance in strict wall thickness situations

67 Cascadia Clip Calculator: Inputs Horizontal spacing goes along with studs With light cladding and low wind loads, possible skip studs For concrete backups start at 24, usually Calculator goes up to 20psf, which covers most claddings Have done projects up to 28psf, just get in contact with us to help with the spacing

68 Cascadia Clip Calculator: Example

69 Cascadia Clip Calculator: Outputs Table and graphs show the same thing Thermal results are full-wall effective R-values Structural results have a FOS of 3.0 built in

70 Cascadia Clip Calculator: Optimizing Find the smallest clip at the largest spacing to minimize # of clips used Example: Project requires an R-15.6 wall, and the cladding must resist 60psf of suction pressure on the cladding.

71 Cascadia Clip Calculator: Easy Submittals Print results, and accompanied by engineering letters that validate the results, can be used as submittal documents Engineering letters located as links on the calculator page

72 Cascadia Clip projects High-profile and interesting projects across the US

73 State University of New York- Medical School 8 stories 540,000SF 2 blue & 4 red clips Horizontal type Largest building constructed in Buffalo in decades Designed by HOK

74 Bullitt Center 6 stories 52,000SF 3.5 orange clips Horizontal type First Living Building Challenge certified commercial buiding in North America Designed by Miller Hull Partnership

75 Zurich North America Headquarters 11 stories 735,000SF 3 purple clips Horizontal type LEED Platinum Certified Clips only used on soffit (middle building) Designed by Clayco

76 Portland University- Collaborative Life Sciences Building 12 stories 650,000SF 3.5 orange clips Vertical type LEED Platinum Designed by SERA Architects and CO Architects

77 MIT- Nanoscale Research Building 4 stories 200,000SF 3.5 orange clips Horizontal type Two floors of highperformance cleanrooms Designed by Wilson Architects

78 Denver Botanic Gardens Science Pyramid Pyramid structure 5,300SF 4 red and 5 yellow clips Vertical type Highly unique sloped roof/wall construction Designed by BURKETTDESIGN

79 Phoenix Airport- Terminal 3 Modernization 3 stories 676,000SF 3.5 orange clips Vertical type New high-performing terminal in three phases to replace outdated existing terminal Designed by DWL Architects, Corgan, and Smithgroup JJR

80 Menil Drawing Institute 1 story 30,000SF 4 red clips Horizontal type First exhibition space of its kind Designed by Johnston Marklee

81 Why Cascadia Clip? Cascadia Clip Adjustability happens entirely outboard of the insulation Cladding attachment is a Z or a hat, both incredibly strong shapes Cascadia Clip matches insulation, thermal break for entire depth of insulation Cascadia clip maintains thermal performance even at very tight spacing Metal Clip & Rail Systems Adjustable rails penetrate insulation L-angle cladding attachment not very strong (much more likely to deflect) Thermal break is only a small portion of insulation depth Thermal performance relies on large spacing of clips: not always possible with various claddings

82 Why Cascadia Clip? Fiberglas Z-girt? Cascadia Clip Composite Systems Insulation Screws are directly fastened through the entire clip: Screws reduce thermal performance slightly (allowably) Screws allow for non-combustible construction Strength comes from screws, thick fiberglass allows for shear support up to 30psf cladding Best thermal performance Combustible structural connection Generally lower strength than metal Thinner webs mean lower strength Pull-out may be an issue

83 Cascadia Clip: Adjustability Recently added adjustability options to deal with uneven substrates Vertical version: clip-specific adjustable brackets Horizontal version: clip-specific adjustable shims

84 Code Compliance: IAPMO-UES Report Third party certification of the Cascadia Clip Approves clip for use in IBC Types I, II, III, IV, and V construction ICC-ES equivalent Looks at several different aspects of design Only clip system with a nationally recognized third party code compliance report

85 Questions?