Passive House Principles for Hot Humid Climates

Passive House Strategies for
Hot and Humid Climates
Gulf Coast Green 2013
Hot and Humid Climates
© Passive House Institute US 2013 1

Overview
1 Passive House Core Philosophy
2 Passive Building Metrics and Principles
3 Climate Specificity3 Climate Specificity
4 Enclosure Strategies
2© Passive House Institute US 2013

Passive House Core Philosophy
Part One: Passive Building Principles

Optimize Orientation
Super-insulate + Air Seal
Optimize Window Performance
Passive House Design Order of Operations
Optimize Window Performance
1st Utilize Passive Space Conditioning Strategies
2nd Utilize High Efficiency Active Strategies
Then…Zero Out with Onsite Renewables

…then zero out the remaining energy with active PV
and generate plus energy for electric mobility…
Passive Buildings: Most affordable Way
to make Zero / Plus Energy Reality
(Image source: Terry Hill, Berlin Germany)

Conventional Approach:
Sizing Mechanical Systems
(over)size the system to the shell

Conventional Approach:
Passive House Approach:
Sizing Mechanical Systems
Size the Shell to the Heating System

Passive Building Metrics and
Principles

Global CO2-Emissions 2006 per Country –
determining a Carbon Metric
Countries by carbon dioxide emissions in thousands of metric tones per annum,
via the burning of fossil fuels (blue the highest)
(Source: Wikimedia Commons 2006)

1000
1200
1400
1600
1800
energy-efficiency
new
geo-/ozean. power
solar
windpower
waterpower
new biomass
trad. Biomass
Worldwide Energy Resources and Consumption
0
200
400
600
800
1890 1910 1930 1950 1970 1990 2010 2030 2050 2070 2090
trad. Biomass
nuclear
gas
oil
coal
Reference: Shell-Study (till 2005), Scenario with high efficiency and regenerative usage of energy

K
Standards & Rating Comparison

One Certification – Three Labels
PHIUS+, Challenge Home, Energy Star V3
Mostly PrescriptiveMostly Performance
Step1: 15-30%Step 2: 40-60%Step 3: 70-85%
100
±±±±0

One Certification – Three Labels
PHIUS+, Challenge Home, Energy Star V3

The 2030 Challenge Brought Forward by Architect Ed Mazria
Passive Buildings
14
Passive Buildings
© Passive House Institute US 2013

Human Comfort Cold Winter
Interior
Feels chilly and drafty: uncomfortable!
Conventional Code
House – Typ. 2x4 wall
(actual R 10)
Double glazed window – R 3
Factors affecting
Comfort:
• Air Temperature (dry
bulb º F)
• Relative Humidity (%)
•Air Velocity (ft/min)
Outside
Temperature 0º F
Glass
Surface
51.2º F
Interior
Walls 68º F
Exterior
Walls 62.9º F
• Radiant Conditions
(MRT º F or radiation value
BTUh/ft²)
RH:
20-50%

Human Comfort Cold Winter
Interior
Feels: comfortable!
Temperate glass and wall surfaces and no drafts
PH Example
• R 60Envelope
PH Comfort criteria:
• (68 º F)Air Temp
Glass
Surface
62.4º F
Interior
Walls 68º F
• R -9 Triple glazed
(Climate specific)
Window
• 0º F
Outside
Temp
Exterior
Walls 67.1º F
RH:40-50%
• (40-60 % for
PH)
Relative
Humidity
• (<19.7
ft/min)
Air
Velocity
• Max Delta T
<7.2 º F (4
ºC)
Radiant
Condition

Human Comfort Hot Summer
Interior
Feels hot and humid: uncomfortable!
Conventional Code
House – Typ. 2x4 wall
(actual R 10)
Double glazed window – R 3
Factors affecting
Comfort:
• Air Temperature (dry
bulb º F)
• Relative Humidity (%)
Outside Temperature
95 º F
Glass
Surface
81.4º F
Interior
Walls 77 º F
Exterior Walls
78.3º F
• Radiant Conditions
(MRT º F or radiation value
BTUh/ft²)
RH:
65-80%

Human Comfort Hot Summer
Interior
Feels: comfortable!
Temperate glass and wall surfaces and no drafts
PH Example
• R 30Envelope
PH Comfort criteria:
• (77 º F)Air Temp
Glass
Surface
79.7º F
Interior
Walls 77º F
Exterior
Walls 77.4º F
RH: 40-60%
• R -5 Triple glazed
(Climate specific)
Window
• 95º F
Outside
Temp
• (40-60 % for
PH)
Relative
Humidity
• (<19.7
ft/min)
Air
Velocity
• Max Delta T
<7.2 º F (4
º C)
Radiant
Condition

PH “thermos bottle”
summer comfort with
RH, range without
active cooling:
Natural Ventilation and
Passive Cooling Strategies?
Fig. 4.186 Applicability of building cooling strategies. Alison Kwok, Walter Grondzik: The Green Studio
Handbook, 2e

Adaptive Comfort

•< 15 kWh/m²a (4.75 kBTU/ft2yr)
Annual Heat
Demand
•< 10 W/m²or 0.93W/ft2 (3.17
BTU/hr.ft2 )
Peak Heat Load
•< 120 kWh/m²a (38 kBTU/ft2yr)
Primary Energy
Demand
• ≤≤≤≤ 0.6 ACH50
Airtightness
Baseline Criteria - Heating
*Note: Window and Thermal
envelope criteria Listed are for a
cool moderate heating dominated
Climate. Recommendations for
these values may vary based on
climate
• ≥≥≥≥75% Recovery, ≥0.45 W/m³ (0.76
W/cfm)
Ventilation
•U ≤≤≤≤ 0.15 W/m2 K (R ≥≥≥≥ 38.5 hr.
ft2°F/BTU,)
Thermal Envelope:
•Ψ ≤≤≤≤ 0.1 W/ mK
Thermal-bridge Free
•Uw-install ≤≤≤≤ 0.85 W/m2 K
Windows installed:
•50 – 55 %SHGC
≈10 W/m² or
1 W/ft²

•< 15 kWh/m²a (4.75 kBTU/ft2yr )
Annual Cooling
Demand
•< 10 W/m²or 0.93W/ft2 (3.17
BTU/hr.ft2 )
Peak Cooling
•< 120 kWh/m²a (38 kBTU/ft2yr)
Primary Energy
Demand
• ≤≤≤≤ 0.6 ACH50
Airtightness
Baseline Criteria - Cooling
*Note: Criteria in blue are
based on a Central European
heating dominated climate.
Recommendations for these
values will vary In N America
cooling dominated climates!
• ≥≥≥≥XX% Recovery, ≥0.45 W/m³ (0.76
W/cfm)
Ventilation Cooling
•U ≤≤≤≤ 0.15 W/m2 K (R ≥≥≥≥ 38.5 hr.
ft2°F/BTU)
Thermal Envelope:
•Ψ ≤≤≤≤ 0.1 W/ mK
Thermal-bridge Free
•Uw-install ≤≤≤≤ 0.85 W/m2 K
Windows installed:
•50 – 55 % (??)SHGC
≈10 W/m² or
1 W/ft²

Five Main Passive Building Principles
+ Renewables= Zero/Plus Energy
Envelope Losses
+ Gains
HP Windows Losses
+ Gains
Balanced Ventilation +
Heat/Moisture Recovery
23
Airtightness
Losses + Gains
Hygrothermal
Performance
Passive Energy
Balancing as Basis for
Zero/Plus Energy

Structural insulated panels
P1: Continuous Insulation
Insulated Concrete Forms
Masonry Structure w/Foamglass
Various Passive House applicable
Wall Type Sections

P1: Avoiding Thermal Bridging
25
Source: Building Science Corporation Newsletter #49: Aqua Tower and Infra Red by Fluke Corp

P2+3: Continuous Air-Tight & Wind-Tight
Layer- The Red line Rule
Air-tight Layer: 0.6 ACH50!Factors affected by air
tightness:
• Moisture Performance
of wall
• Heat loss through
RED LINE RULE
• Draw continuous air
barrier
Wind tight Layer
• Heat loss through
leaks
• Comfort, no drafts!
barrier
• Identify each air
barrier component
• Identify connection
between them

P4: High Performance Windows(PHI2006)
Definition of a thermal bridge:
A building element which has a
linear thermal transmittance of
greater than 0.006 BTU/(hr ft °°°°F)

The highly efficient Window Profile – warm
climates, SHGC needs to be minimized!
Exterior surface
temperatures can
get to 160 F!

Passive Solar Opportunities
and Challenges

Venetian Blinds, trellises,
overhangs, balconies, decks,
trees etc.
Exterior Shading Devices
http://www.warema.com

1. Ventilation
2. Dehumidification
3. Cooling
P5: Balanced Ventilation System
With Minimal Space Conditioning
3. Cooling
4. Heating
5. Domestic Hot
Water
31
Image source: www.greenbuildingstore.co.uk/mvhr.php

• A
Most Popular Ventilation Models
UltimateAir 200DX (ERV)Zehnder ComfoAir 350
(ERV/HRV)

Night-time cooling
Passive Cooling
(Image Source: passive-on.org)
PH Cooling-Passive Design Strategies
Ground cooling Source: Zehnder
Heat Recovery BypassGround Temperature @ 3-4m (10-13 ft) =
Annual Mean Air Temperature ±±±±2 ºC (4 ºF)
Radiative cooling
Evaporative cooling

Heating, Cooling and Dehumidification
(Images:http://compressors.danfoss.com/)
Samsung Mini-Split Air-to-Air Heatpump 20 SEER, point source
Samsung EH slim ducted Mini-
Split, integrated in ventilation
ductwork

Heating and DHW
(Image: www.enerworks.com)

Heating Degree DaysHeating Degree Days
Cooling Degree DaysCooling Degree Days
Winter Design TempratureWinter Design Temprature
Summer Design TemperatureSummer Design Temperature
Passive Building is Climate Dependent!!
Summer Design TemperatureSummer Design Temperature
HumidityHumidity
Solar RadiationSolar Radiation
Night Sky RadiationNight Sky Radiation
Ground TemperatureGround Temperature

Latent vs Sensible Ventilation Load
Indexes
U.S. has more climate zones
than the
entire European Union!!
(Image Source: from ASHRAE Journal, November, 1997 pp 37 - 45)
Image Source: www.energycodes.gov

Climate Specific Space Conditioning
Requirements
Graph Courtesy of Global Buildings Performance Network

400
600
800
1000
1200
Qlatent(watts)
Nov
Dec
Jan
Feb
Mar
Apr
heating and
dehumidification
cooling and
dehumidification
66-76F
-400
-200
0
200
-3000 -2500 -2000 -1500 -1000 -500 0 500 1000 1500 2000
Qsensible (watts)
Qlatent(watts)
Apr
May
June
July
Aug
heating and humidification
cooling and
humidification
30-
60%rh
Grafics: Newell Instruments, Inc.

SI Units IP
1 Heat Load: ≤10 W/m2 ≤ 1 W/ft2
Cooling Load: ≤ 8 W/m2 ≤ 0.8 W/ft2
2 Envelope Insulation:2 Envelope Insulation:
Very Cold/humidVery Cold/humid Minneapolis, MNMinneapolis, MN U≤0.08 W/mU≤0.08 W/m22KK R≥71 hrR≥71 hr--ftft22--°°F/BtuF/Btu
ColdCold Chicago, ILChicago, IL U≤0.094 W/mU≤0.094 W/m22KK R≥60 hrR≥60 hr--ftft22--°°F/BtuF/Btu
Mixed/humidMixed/humid Ashville, NCAshville, NC U≤0.14 W/mU≤0.14 W/m22KK R≥40 hrR≥40 hr--ftft22--°°F/BtuF/Btu
Mixed/dryMixed/dry Las Vegas, NVLas Vegas, NV U≤0.14 W/mU≤0.14 W/m22KK R≥40 hrR≥40 hr--ftft22--°°F/BtuF/Btu
MarineMarine Seattle, WASeattle, WA U≤0.13 W/mU≤0.13 W/m22KK R≥44 hrR≥44 hr--ftft22--°°F/BtuF/Btu
Hot/humidHot/humid Houston, TXHouston, TX U≤0.16 W/mU≤0.16 W/m22KK R≥35 hrR≥35 hr--ftft22--°°F/BtuF/Btu
Climate Specific Recommendations Passive House
Hot/humidHot/humid Houston, TXHouston, TX U≤0.16 W/mU≤0.16 W/m KK R≥35 hrR≥35 hr--ftft --°°F/BtuF/Btu
Hot/dryHot/dry Phoenix, AZPhoenix, AZ U≤0.16 W/mU≤0.16 W/m22KK R≥35 hrR≥35 hr--ftft22--°°F/BtuF/Btu
3 Thermal Bridge Free Construction:3 Thermal Bridge Free Construction:
Linear Thermal TransmittanceLinear Thermal Transmittance ΨΨ≤0.01 W/≤0.01 W/mKmK ΨΨ≤0.006 Btu/hr≤0.006 Btu/hr--ftft--°°FF
4 High Performance Windows installed:4 High Performance Windows installed:
Overall Thermal Transmittance (Very Cold)Overall Thermal Transmittance (Very Cold) UU≤0.6 W/m≤0.6 W/m22KK UU≤0.11 Btu/hr≤0.11 Btu/hr--ftft22--°°FF
Overall Thermal Transmittance (Cold/Mixed)Overall Thermal Transmittance (Cold/Mixed) UU≤0.85 W/m≤0.85 W/m22KK UU≤0.15 Btu/hr≤0.15 Btu/hr--ftft22--°°FF
Overall Thermal Transmittance (Hot)Overall Thermal Transmittance (Hot) UU≤1.55 W/m≤1.55 W/m22KK UU≤0.27 Btu/hr≤0.27 Btu/hr--ftft22--°°FF
Solar Heat Gain Coefficient (Mixed/Cold) g-value≥50% SHGC≥50%
Solar Heat Gain Coefficient (Hot) g-value ≤ 30% SHGC ≤ 30%
5 Heat Recovery Ventilation:
Net Efficiency η≥80% η≥80%
Electric Consumption of motor ≤0.45 Wh/m3 ≤0.76 W/cfm

Climate on the Move
Source: www.globalchange.gov

Cold and Humid Climate Wall Assembly - Chicago
Vapor Drive
End of Feb
End of Oct
End of Jul
Spring and Fall
Winter
SummerEnd of Jul Summer

Wall Assembly Warm Humid Climate -Houston
Vapor Drive
End of October
End of February
End of July
Spring and
Fall
Winter
Summer

Orientation and Shading a Must:
Windows to the N, S and E-W limited
46

LeBois Project – 2010, Lafayette, LA
47

North American Passive Building
Uptake 2003-2013

PHIUS Certifications over
last 10 Years in US and Canada

PHIUS Certification Programs:
PHIUS Certification Programs
PHIUS Certification
Mark
® ®
PHIUS Certification Programs:
Certified Passive House Consultant, CPHC®
PHIUS Certified Builder
PHIUS+ Certified Rater
PHIUS+ Certified Passive House Projects
Window Performance Data Verification Program
Mark

PHIUS+ Certified Passive Projects
www.passivehouse.us/projects
48 certified and
pre-certified
Projects,Projects,
Total of more
than 130
projects
currenty
Registered in
National Data
Base to be
completed!

www.passivehouse.us/consultants
Certified Passive House Consultants (CPHC®)
421 Certified
ProfessionalsProfessionals
currenty listed
in National
Data Base!

Save the Date!
October 16-19, 2013
8th Annual North American Passive House
7th7th7th7th Annual North American Passive House ConferenceAnnual North American Passive House ConferenceAnnual North American Passive House ConferenceAnnual North American Passive House Conference
September 27September 27September 27September 27----30, 2012 Denver CO30, 2012 Denver CO30, 2012 Denver CO30, 2012 Denver CO
8th Annual North American Passive House
Conference, Pittsburgh, PA
Katrin Klingenberg
katrin@passivehouse.us
Executive Director | PHIUS

Thank You!Thank You!
Questions?

Passive House Principles for Hot Humid Climates

Recomendados

Recomendados

Más contenido relacionado

La actualidad más candente

La actualidad más candente (20)

Similar a Passive House Principles for Hot Humid Climates

Similar a Passive House Principles for Hot Humid Climates (20)

Más de aiahouston

Más de aiahouston (18)

Último

Último (20)

Passive House Principles for Hot Humid Climates