Designing & Selecting Windows & Doors for Passive House€¦ · R-Value 0.31 0.28 0.28 0.29 0.2...
Transcript of Designing & Selecting Windows & Doors for Passive House€¦ · R-Value 0.31 0.28 0.28 0.29 0.2...
Bronwyn Barry
Designing & SelectingWindows & Doors for Passive House
Overview:
• Basic Concepts & Anatomy• The evolution of PH windows• Basic PHPP inputs• Optimizing your design for PHPP• Shading (your new best friend)• Comfort Index (Does triple pane actually make sense?)• Cost/Benefit Analysis (can your windows pay for themselves?)• Carbon Footprint
Why windows matter…Back to basics:
Windows (& glass doors) both HEAT and COOL your building
Window Fundamentals & Anatomy:
FrameSashSpacer BarGlazing
SHGCVT
U-factor
Scanned from: Residential Windows by John Carmody et al
U-FACTOR and why it matters
Scanned from: Residential Windows by John Carmody et al
0.690.30.790.510.730.610.43VT
0.520.20.540.30.430.350.18SHGC
97.153.443.573.573.22R-Value
0.110.140.20.290.280.280.31U-Value
Triple -pane Low E Argon
filled
Xenon Dual Pane, 3 High
SHG filmsLow E Argon
filledLow E II
Argon filledLow E 4Insulated Low E II
Low E 363 Argon filled
Glazing
Insulated Fiberglass clad
1125 Series Insulted Fiberglass
Westfalenseries, all wood
Ultrex clad wood casement
Casement/Awning Vinyl-clad
All wood Poly & Rectangles
Primed, push-out casementSeries
ENERsign*
Serious Mat'rlsSorpetaler*
Marvin UltrexAndersenMarvinJeld-WenValue
Performance Rating Values Comparison (Source: Manufacturer’s websites, based on NFRC
testing. All numbers for 2040 casement windows. * Based on ASTM & Passive House Institute testing info. NFRC ratings for the two German windows currently in progress.)
Performance comparison
Source: Straube, John; Can Highly Glazed Building Facades Be Green?, Building Science Insights, BSI-006, www.buildingscience.com, September, 2008.
How windows affect your walls
Darwinian theory for windows…
Source: ARCHnews Green Column, June 2009. Dan Johnson, [email protected]
‘Basic’ PHPP inputs…
5.410.190.540Your glazing name here1
hr.ft2.F/BT
U
BTU/hr.ft2.
F
Rcog-
Value
Ucog-
ValueSHGCGlazing
Ass
emb
ly
No.
Type
2.8804.8104.7504.7504.7504.7505.000.20Your window name here1
hr.ft2F/BTU.i
n
hr.ft2F/BTU.i
ninininin
hr.ft2.F/BT
U
BTU/hr.ft2.
F
ΨΨΨΨInstallationΨΨΨΨSpacerWidth -
Above
Width -
Below
Width -
Right
Width -
LeftFrameFrameFrame
Ass
emb
ly
No.
Thermal
Bridge
Thermal
Bridge
Frame Dimensi
onsRf-ValueUf-ValueType
Source:
THIS TABLE WAS COPIED FROM A LICENSED COPY OF THE PASSIVE HOUSE PLANNING PACKAGE. Inserted information
should be based on values generated by a third party certifier.
Good, Passive Solar basics…
• Large south-facing windows
• Fewer operable units with less mullions
• NO muntin bars
• Stacked windows on first and second stories
• NO sliders or single- & double-hung windows
Basics (cont.)
Don’t mind the threshold…
• Learn to LOVEthe step-over threshold!
Basics (cont.)
• Exterior SHADING!
Basics (cont.)
• Local Exterior SHADING
WA Design, Berkeley, CA
Where windows lose heat…
Source: Analysis of Heat Loss Reduction through window edges by E. isevieius, V. Staponkus, & A. Jurelionis; Kaunas University of Technology, Lithuania. 2005
The RAINBOW analysis…
Window Cost Benefit Analysis
0
10
20
30
40
50
60
Exist
ing
Av. R
3.4
wind
owSo
rpet
aler
SM 9
25Th
erm
oT
SM 7
25EN
ERsig
n
Window Brand
Window 5 R-value
Heat Dem # (kBTU/ft2yr)
Price $K
Delta HD
The meat of the matter!
Source: Compiled by author from data input into the PHPP for a project in Larkspur, Marin.
*** 11 lbs of CO2 saved for each Therm saved
** Assuming $0.13 per kBTU/ft2yr (1 Therm = 100,000 BTUs = $1.30 @ 2,200sf =$286.00)
Why payback analysis is weak:
Window Payback Analysis
0.020.040.060.080.0
Exis
ting
Av. R
3.4
win
dow
Sorp
eta
ler
SM
925
Therm
oT
SM
725
EN
ER
sig
n
Window Brands
$K Saving/a**
$K for 30yrs
Yrs to paybk
30 yr CO2reduction (lbs) ***
Source: Compiled by author from data input into the PHPP for a project in Larkspur, Marin.
But the ‘Comfort’ factor is strong!
Image source: Stefan Carpentier, Berkeley, CA 2009
Project located in Berkeley, CA
The case for triple pane:
Data Source: Dariush Arasteh– LBNL, private email, 2009.
Map Source: http://resourcecenter.pnl.gov/cocoon/morf/ResourceCenter/dbimages/full/973.jpg
11.110.090.53-4-20Zone 7
10.000.10.65-15Zone 6
8.330.120.714-10Zone 5
7.140.140.8423-5Zone 4
5.560.181.05320Zone 3
2.700.372.15010Zone 2
max. R
W(hr.ft2.°
F/BTU)
max. U
W(BTU/hr.ft2.°F)
max. UW (W/m
2-C)
Min. Outdoor Temp (F)
Min. Outdoor
Temp (C)
Approx. US
Climate Zone
35,000.00126.00700.00Heavy TruckBend, OR to Oakland, CA Jeld-Wen/Pozzi
123,950.00446.222,479.00Heavy TruckWarroad, MN to Oakland, CAMarvin
69,400.16131.778,994.00TOTAL:
65,764.16123.098,792.00PS-Type Containter shipRotterdam, NE to Oakland, CA
3,636.008.69202.00Rail- ElectricDortmund, GE to Rotterdam, NESorpetaler & Pazen
CO2 (g/tkm)*Energy (kWh/tkm)*Distance (km)Transport:Location:Manufacturer:
* Sourced from:www.maerskline.com/globalimage/?path=/about_us/table_of_comparisonEnergy Use & Emissions Calculations
The case for imports…
Did I mention Exterior Shading?
Quantum Builders
For Sustainable Living, Inc.
1454 B 4th Street
Berkeley, CA 94110
Tel: 510.559.3488
Thank you!