201802 bbbd vermont · multi-unit residential à land use, walkable cities, aging population etc...
TRANSCRIPT
18-02-07
1
Dr John Straube, P.Eng. Principal, RDH Building Science
Assoc. Professor, University of Waterloo
Waterloo, Canada
Building Science
2 of
Intro
à Building Science
à Changes and Future Trends
à Three topics
à ci
à Prefabrication
à Housing Types
à Tall Wood Case Study
18-02-07
2
3 of
Changes and Trends
à Changing projects à Retrofit
à Changing / Aging population
à Infill › + In-law units, “granny flats”, etc
à Mid-rise, especially urban › Wood 5, 6 storey +
à Multi-use
à Regional variations (labor vs land price) › Vermont vs Boston vs Kansas vs Seattle
4 of
Changes and Trends
à Changing needs à Lower energy
à More comfort
à Better IAQ
à Faster construction
à Weather insensitivity
à Higher Labor efficiency
18-02-07
3
5 of
Changing Demands
à More insulation à Quality inspection
à Less thermal bridging
à More airtightness
à Blower door testing
à Changing techniques
à Save labor
à Reliably & provably deliver airtightness and thermal bridge reductions
6 of 69
Innovation
à “The industry is slow to change and conservative”
à Of course it is, it should be à Buildings are long term à Buildings are massive investment
à Innovation is NOT something new, it is something better
18-02-07
4
7 of
Innovation
à Technology is improving à Mostly limited by demand from market place
à Triple, quad glazing, Water barriers
à Price is dropping
à Photovoltaics super cheap
à LED lights the norm
à Ductless mini-splits
à Insulation is cheap and relatively less $
8 of 69
Needed Innovation
à Many mechanical system changes
à More heatpump solutions à Central heat systems with sCOP >2.0 at < 0F
à Domestic hotwater solutions à Becoming largest load…
heat pumps not great at 120F water!
à Balanced Ventilation with exhaust appliances
à The price of super airtightness
à We don’t really need our furnace or fridge connected to the internet
18-02-07
5
9 of
Smaller furnaces
à Smaller, more efficient and multi-family buildings need smaller furnances!
à Long run times
à Steady heat
à Smaller ducts
à Poor industry engagement
Dettson Chinook furnace
15KBtu/hr
10 of 69
Future
à More quality assurance and control à E.g., Blower door, infra red scans
à More Prefabrication à Attack labor cost, reliability, weather
à Net Zero Energy Buildings, happening but à Only small % of total use à need to rework grid ….
à Existing buildings and retrofit à Massive current & future energy users à Need comfort, IAQ upgrades
18-02-07
6
11 of
Continuous Insulation
12 of 69
Getting to Higher R-values
Base 2x6 Framed Wall <R-16 (wood)
Exterior Insulation R-15 to R-60+
Deep Stud, Double Stud, SIPS R-20 – R-80+
Split Insulation R-20 to R-60+
Interior Insulation R-20 to R-30+
Issues: cladding attachment, thickness
Issues: thermal bridging, thickness, durability
Issues: thickness, durability, interior details Issues: cladding attachment, material selection
18-02-07
7
13 of From: www.BuildingScience.com
Standard for over 60 years
R-10 to R-19
Interior
air-vapor
barrier
14 of
Used for over 30 years
R-13 to R-40+
Exterior a
ir barrie
r
From: www.BuildingScience.com
18-02-07
8
15 of
R-20 to R-40+
From: www.BuildingScience.com
16 of
R-20 to R-40+
Exterior a
ir barrie
r
18-02-07
9
17 of
Exterior Insulation (“ci”)
à Research and experience have shown it works
à But knowledge not well disseminated
à Uncertainty in practise (not reality)
à Vapor control
à Wetting and drying
à Cladding attachment
18 of
Field “research” / demo
à
18
ccSPF 2x6 I-
joist Dbl stud
3” stonewool
2.5” XPS
2” PIC
18-02-07
10
19 of
Test Wall R-values
à 2x8 with ccSPF only R24
à Others reduce heat flow by half of Code à Walls 5 & 6 have no 6 mil poly
19
20 of
OSB Sheathing MC
N1-OSB M N2-OSB M N3-OSB M N5-OSB M N6-OSB M N7-OSB M
Moi
stur
e C
onte
nt (M
%)
5
10
15
20
Sep Nov Jan Mar May Jul2013 - 2014
Double stud/ I-joist
PIC/XPS no poly
Stonewool
North wall, airtight
18-02-07
11
21 of
Add Calibrated Air leak
21
22 of
Air Leakage
22
N1-OSB L N2-OSB L N3-OSB L N5-OSB L N6-OSB L N7-OSB L
Possible Condensation
Start air injection Stop Air Injection
Moi
stur
e C
onte
nt (M
%)
5
10
15
20
25
30
Jan Feb Mar Apr May2013
Double stud/ I-joist
Datum
Ext Insul.
polyiso
18-02-07
12
23 of
North, I-joist Wall (5 yrs) Samples taken near MC Sensor for mold testing
24 of
North, 2” PIC, FG, no poly
18-02-07
13
25 of
à Panelized
à Modular
à Component
Prefab / Off-site
26 of
Prefab and Modular
Penn State RBDCC Brochure
18-02-07
14
27 of
Prefab
à Promises à Improve labor efficiency, quality
à Reduce weather sensitivity
à Reduce cost
à Challenges à Joints
à Dimensional Control
à Transport / Erection Moisture
28 of
Offsite construction
à We have long done this
à E.g., Windows, stairs, boilers, millwork
à Now, more, larger, lower value components
à Panelized walls
à Modular units
18-02-07
15
29 of
30 of
Panel / Site Process
à Panels & exterior exposed to weather
à Cant do much interior work or MEP
30
18-02-07
16
31 of 69
32 of
Modular Process
à Only exteriors exposed to weather, lots of interior work and MEP can be done
à You are shipping air, and redundant ceiling
18-02-07
17
33 of
à Modular is ideal for:
à Repetitive unit (modules)
à Remote locations - labour
à Locations where construction is disruptive – inner city
à Modular may not be ideal for:
à Open floor layouts such as office spaces
à Complex floor plans
Modular.. And when does it make sense
More $ allows modular everywhere.
34 of
18-02-07
18
35 of
36 of
Expecting? Or … is the tarp leaking?
18-02-07
19
37 of
Temporary roof, weighted to limit blowing off Ponding feature is free
38 of
Rain damage and mold
18-02-07
20
39 of
Toffino, BC… lifting
Manage moisture from factory yard to close in on site
40 of
Your module has landed…now what
18-02-07
21
41 of
PassiveHouse prefab BellaBella
Water resistant side walls
Construction protected windows
42 of
Future growth will be in
à Multi-unit
à Retrofit
à ADU
Types of Housing
42
18-02-07
22
43 of
Multi-unit residential
à Land use, walkable cities, aging population etc demand more multi-unit (not multi-family)
44 of
Fire and sound separation
à High Density / Mixed-use means …
à Better separation
à New techniques of compartmentalization
à Construction sequencing
à Quality control
18-02-07
23
45 of
Renovation & Retrofit
46 of
Retrofits
à Huge existing stock of buildings, means:
à Energy-efficient retrofits must be part of any solution
à Approach varies more than new construction
à Can we just exterior retrofit like siding?
18-02-07
24
47 of
Changing things …
à Changes things
à New windows, new furnace, added insulation à Increased airtightness
à Different temperatures
à Approach
à Add airtightness (add mechanical ventilation)
à Add exterior insulation (improve rain control)
48 of 69
Accessory Dwelling Units
From: www.BrightBuiltHome.com
From: modularlifestyles.com
Zoning & State laws changes Provides affordable housing and reflects changing demographics
18-02-07
25
49 of
à The resurgence of wood in tall and large buildings
Tall Wood
50 of 69
Mass/Heavy Timber – Engineered Materials
à Taller structures require heavier timber & engineered lumber components à Cross Laminated Timber (CLT)
à Nail Laminated Timber (NLT)
à Glulam
à Laminated Strand Lumber (LSL)
à Parallel Strand Lumber (PSL)
à Laminated Veneer Lumber (LVL)
à Many tall wood structures will also incorporate steel and concrete
CLT
NLT
18-02-07
26
51 of 69
New Tall Wood – Montreal Multifamily
CLT
52 of 69
New Tall Wood – Minneapolis Office Building
NLT
18-02-07
27
53 of 69
Some Potential Risks and Challenges with Mass Timber
54 of 69
Case Study - UBC Dorms
à 18 storey, tall wood
à CLT, Glulam
à Enclosure fabricated offsite
18-02-07
28
55 of 69
Structural System:Wood+Concrete
56 of 69
Structural System – Concrete Core
à
18-02-07
29
57 of 69
Structural System – Glulam Columns
58 of 69
Structural System – CLT Floors
18-02-07
30
59 of 69 Concrete, Steel and Wood -Hybrid Structure
60 of 69
Wall Panelization & Window Installation in Factory
18-02-07
31
61 of 69
Wall Panelization & Window Installation in Factory
62 of 69
Site Installation – Perimeter Angle
18-02-07
32
63 of 69
Site Installation – Panel Hoisting
64 of 69
Sealing joints
18-02-07
33
65 of 69
Sealing Joints
66 of 69
Note open steel stud frame
Services and seamless finish now installed
18-02-07
34
67 of 69
Exterior near completion
68 of 69
In closing
à Many new changes and demands
à Need to change what we do à Housing forms à Higher expectations à More reliably delivered
à Build on our knowledge and experience, not reinvent
à But much of industry still needs to learn a lot about building science … à Need to train next generation
18-02-07
35
69 of 69
à rdh.com | buildingsciencelabs.com
Building Science
Thank you
JOHN STRAUBE
Building Science