The document presents a case study of the Minnephit House, the first cold-climate EnerPHit project, emphasizing passive house standards for energy efficiency in retrofitting residential buildings. It outlines goals for performance, design, construction details, and provides energy modeling metrics alongside challenges and strategies for achieving passive house certification in existing structures. The results demonstrate significant energy savings and improvements in indoor comfort while meeting sustainability standards.

1. Residential Passive House Retrofit (EnerPHit)
The MinnePHit House
Case Study about the first cold-climate EnerPHit project in the World
Tim Eian, Dipl.-Ing., Certified Passive House Planner & Consultant

2. Learning Objectives
• The Passive House building energy standards
• Residential Passive House retrofit design
• Strategies, materials and systems
• Challenges & Opportunities
• Certification

3. Introduction

4. Photos: Corey Gaffer
The MinnePHit House
Minneapolis, MN

5. before

6. after

8. Photos: Corey Gaffer

10. Photos: Corey Gaffer

11. Minneapolis
+ EnerPHit
= MinnePHit

12. The
Passive House Standard

13. Passivhaus - Passive House
“A rigorous, voluntary building energy standard
focusing on highest energy efficiency and quality of life
at low operating cost.”

14. Passive House in 90 Seconds
Video: Hans-Jörn Eich

15. Think globally, build locally.
Global Standard

16. Global Adoption

17. Third-Party Certified

18. Tool

19. The Path to Ultimate Sustainability

20. Global Climate Specificity

21. Climate-Specific Requirements

22. Energy Modeling

23. Conservation first
➡ Minimize losses
➡ Maximize (free) gains
Basic Concept

24. Active vs. Passive
Passive: 4.75 kBtu/(sf yr)Active: 25-125 kBtu/(sf yr)
85 - 450 kWh/(m2 a), typically found in the U.S. 15kWh/(m2 a), maximum target
Source: Krapmeier & Drössler 2001

25. Energy Footprint
Heating (active)
Hot water (active)
Cooling (active)
Household Electricity
Heat & hot water (passive)
➡ up to 95% less heating energy
➡ 50 to 75% less total energy
Code Passive House

26. Energy per Square Foot and Year
Gas mileage for buildings.
Metrics

27. ≤ 4.75 kBtu/(sf yr)
≤ 15kWh/(m2
a)
Total energy used to heat or cool a building.
Space Conditioning Energy Targets
≤ 7.9 kBtu/(sf yr)
≤ 25kWh/(m2
a)
≤ 9.5 kBtu/(sf yr)
≤ 30kWh/(m2
a)

28. ≤ 38 kBtu/(sf yr)
≤ 120kWh/(m2
a)
Total energy used to heat or cool a building.
Source Energy Targets
varies
≤ 120 kWh/(m2
a) + ((QH - 15 kWh/(m2
a)) * 1.2)

29. ≤ 3.17 Btu/(h sf)
≤ 10W/m2
Heating energy can be supplied through ventilation system.
Heating Load Target (suggested)

30. ≤0.6 ACH50
Measured with a blower door in the field.
Airtightness Targets
≤1.0 ACH50

31. EnerPHit offers a Component Track.
Component Targets
• Maximum U-values
• Minimum R-values
• SHGC requirements
• Minimum heat-recovery rates

32. Component Targets

33. Predictable Outcome & Measurable Results
Passive House Planning Package - PHPP

34. Key Benefits

35. Highest Comfort

36. Superior Indoor Environmental Quality

37. Image Source: dreamstime.com
Ecology and Resource Efficiency

38. Image Source: dreamstime.com
Cheapest Life Cycle Cost

39. The
MinnePHit Project

40. Where are we?

41. Image Source: carlustblog.org
what we got

42. 1935

47. • 2 stories + basement
• 1,200 finished SF
• 2 bedrooms
• 1 bath
• 5 people

49. Prior Airport Noise Retrofit

50. Windows with Storms

51. Mechanicals

52. Airtightness
Initial Test
8.5 ACH50 [2,100 CFM50]

53. Pre-Existing Conditions

59. • Structure ✓
• Weather Barrier?
• Insulation ✗
• Airtightness ✗
• Moisture Management ✓
• Ventilation/ Air Quality ✗
• Comfort ✗ ✗
• Daylight ✗
• Durability (30 years?)
• Design (Sign of the Times)
So, Where Are We?

60. Where do we go?

61. Image Source: Wikipedia
what we need

62. • + 3 Bedrooms
• + 2 Baths
• + Mudroom
• Better kitchen
• Better living areas
• Homeschool room
• Safe stairs
• Weather-tight envelope
• Durable structure
• Healthy interiors
• Comfort & daylight
• Low operating cost
• Energy performance
The List

64. Passive House Institute
Dr. Wolfgang Feist
Rheinstraße 44/46
64283 Darmstadt
Germany
www.passivehouse.com
EnerPHit and EnerPHit+i
Certification Criteria for Energy Retrofits with Passive House Components
If an energy retrofit of an existing building meets Passive House criteria (for new builds), it,
too, can be certified as a Certified Passive House.
It is, however, often difficult to feasibly achieve the Passive House Standard in older
buildings for a variety of reasons. Passive House technology for relevant building
components in such buildings does, nevertheless, lead to considerable improvements with
respect to thermal comfort, structural longevity, cost-effectiveness over the building lifecycle
and energy use.
Buildings that have been retrofitted with Passive House components and, to a great extent,
with exterior wall insulation can achieve EnerPHit certification as evidence of both building
quality and fulfilment of specific energy values. The EnerPHit+i
designation is applied if
more than 25 % of the opaque exterior wall surface has interior insulation.

65. How do we get there?

66. Holistic Energy Reduction Retrofit
≠
Weatherization

67. Sports car?

68. • Set goals for performance and design
• Overlay architectural program
• Make the home safe for people (code compliance)
• Control temperature, air, and moisture
• Add ventilation
• Make the envelope air- and weather-tight
• Add continuous insulation to meet the energy goals
• Assess moisture transfer through shell
• Implement robust climate zone-appropriate assemblies
• Reduce energy demand by 2/3 and air-leakage 10X to
meet Passive House retrofit standard (EnerPHit)
The Plan for Success

69. The Concept

70. REPLACE GLASS BLOCK
W/ EGRESS WNDWS
DEMO GLASS BLOCK
& FILL TO MATCH
FND. WALL
PERIMETER OF STRUCTURE ABOVE
CHIMNEY ABOVE
DEMO STAIR
DEMO AND REPLACE
LOAD BEARING WALL
& FOUNDATION
TEMP. BRACE FLOOR
UP
2x10s
@ 16" O.C.
2x10s
@ 16" O.C.
UNEXCAVATED
DEMO FLOOR SLAB
& EXCAVATE FOR NEW
ASSEMBLY
LAUNDRY ROOM WORKOUT ROOM
BATH
- DEMO & SALVAGE FIXTURES
Basement

71. 1. Homeschool Room
2. Mechanical
3. Unexcavated
3
1 2 3
UP
Basement

72. REPLACE GLASS BLOCK
W/ EGRESS WNDWS
DEMO GLASS BLOCK
& FILL TO MATCH
FND. WALL
PERIMETER OF STRUCTURE ABOVE
CHIMNEY ABOVE
DEMO STAIR
DEMO AND REPLACE
LOAD BEARING WALL
& FOUNDATION
TEMP. BRACE FLOOR
UP
2x10s
@ 16" O.C.
2x10s
@ 16" O.C.
UNEXCAVATED
DEMO FLOOR SLAB
& EXCAVATE FOR NEW
ASSEMBLY
LAUNDRY ROOM WORKOUT ROOM
BATH
- DEMO & SALVAGE FIXTURES
UP
1. Retrofit
2. Reconstruction
3. Addition
Basement

73. SOFFIT
BRICK CHIMNEY,
SEAL AIRTIGHT
DEMO EXIST. SOFFIT
REMOVE AND SALVAGE
WNDWS, TYP.
REMOVE AND SALVAGE
DOORS AS INDICATED
DEMO LANDING
DEMO STAIRS,
UP AND DOWN
UP
DN
DN
DN
DN
2x10s
V.I.F.
2x10s
V.I.F.
2x
V.I.F.
LIVING ROOM
KITCHEN
- DEMO ALL BUILT-INS
- DEMO & SALVAGE EQUIPMENT
DINING ROOM
KID'S ROOM
ENTRY VEST.
DEMO FLOOR SYSTEM
ABOVE SLAB
DEMO FLOOR SYSTEM
ABOVE SLAB
First Floor

74. REF
D W
1. Entry
2. Powder room
3. Mud room/ laundry
4. Living room
5. Kitchen
6. Dining area
7. Family area
8. Covered entry
9. Rear entry
10.Patio
1 2 3
4 5
7
8 9
10
6
First Floor

75. SOFFIT
BRICK CHIMNEY,
SEAL AIRTIGHT
DEMO EXIST. SOFFIT
REMOVE AND SALVAGE
WNDWS, TYP.
REMOVE AND SALVAGE
DOORS AS INDICATED
DEMO LANDING
DEMO STAIRS,
UP AND DOWN
UP
DN
DN
DN
DN
2x10s
V.I.F.
2x10s
V.I.F.
2x
V.I.F.
LIVING ROOM
KITCHEN
- DEMO ALL BUILT-INS
- DEMO & SALVAGE EQUIPMENT
DINING ROOM
KID'S ROOM
ENTRY VEST.
DEMO FLOOR SYSTEM
ABOVE SLAB
DEMO FLOOR SYSTEM
ABOVE SLAB
1. Retrofit
2. Reconstruction
3. Addition
REF
D W
First Floor

76. BRICK CHIMNEY
DEMO STAIR &
LANDINGS
DEMO
BALCONY
REMOVE AND SALVAGE
WNDWS, TYP.
REMOVE AND SALVAGE
DOORS AS INDICATED
DN
DN
DN
DN
MASTER BEDROOM BEDROOM
BATH
- DEMO & SALVAGE FIXTURES
OFFICE
DEMO ROOF SYSTEM
ABOVE ENTRY
Second Floor

77. 1. Bedroom 1
2. Bedroom 2
3. Master Bedroom
4. Master Closet.
5. Master Bath
6. Bedroom 3
7. Kid’s Bath
8. Toilet Room
1
7
8
2
36
5
4
Second Floor

78. BRICK CHIMNEY
DEMO STAIR &
LANDINGS
DEMO
BALCONY
REMOVE AND SALVAGE
WNDWS, TYP.
REMOVE AND SALVAGE
DOORS AS INDICATED
DN
DN
DN
DN
MASTER BEDROOM BEDROOM
BATH
- DEMO & SALVAGE FIXTURES
OFFICE
DEMO ROOF SYSTEM
ABOVE ENTRY
1. Retrofit
2. Reconstruction
3. Addition
Second Floor

79. PASSIVE SOLAR
HEAT GAINS(WINTER)
SOLAR
SHADING
(SUMMER)
HEAT-RECOVERY
VENTILATION &
SMALL HEATER
AIR-INTAKE
EXHAUST
LARGE "ACTIVE"
MECHANICAL SYSTEM
- FURNACE OR BOILER
EXISTING CONDITION
- INSUFFICIENT INSULATION
- LOW-PERFORMANCE
WINDOWS AND DOORS
- AIR LEAKAGE
- NO VENTILATION
EXTRACT AIR
SUPPLY AIR
INTERNAL
HEAT GAINS
- PEOPLE
- EQUIPMT.
RETROFIT CONDITION
- WATER PROOFING
AND MANAGEMENT
- ADDED INSULATION
- MITIGATION OF
THERMAL BRIDGES
EXISTING CONDITION
- NO WATER PROOFING
AND MANAGEMENT
- NO INSULATION AT AND
BELOW GRADE
- THERMAL BRIDGES
TYPICAL EXISTING BUILDING (BEFORE)DEEP ENERGY REDUCTION RETROFIT (AFTER)
OPTIONAL SOLAR THERMAL
OR SOLAR PHOTOVOLTAIC
RETROFIT CONDITION
- ADVANCED WINDOWS
AND DOORS
- AIR-TIGHTNESS LAYER
- CONTINUOUS INSULATION
PACKAGE
Retrofit Concept

80. PASSIVE SOLAR
HEAT GAINS(WINTER)
SOLAR
SHADING
(SUMMER)
HEAT-RECOVERY
VENTILATION &
SMALL HEATER
AIR-INTAKE
EXHAUST
LARGE "ACTIVE"
MECHANICAL SYSTEM
- FURNACE OR BOILER
EXISTING CONDITION
- INSUFFICIENT INSULATION
- LOW-PERFORMANCE
WINDOWS AND DOORS
- AIR LEAKAGE
- NO VENTILATION
EXTRACT AIR
SUPPLY AIR
INTERNAL
HEAT GAINS
- PEOPLE
- EQUIPMT.
RETROFIT CONDITION
- WATER PROOFING
AND MANAGEMENT
- ADDED INSULATION
- MITIGATION OF
THERMAL BRIDGES
EXISTING CONDITION
- NO WATER PROOFING
AND MANAGEMENT
- NO INSULATION AT AND
BELOW GRADE
- THERMAL BRIDGES
TYPICAL EXISTING BUILDING (BEFORE)DEEP ENERGY REDUCTION RETROFIT (AFTER)
OPTIONAL SOLAR THERMAL
OR SOLAR PHOTOVOLTAIC
RETROFIT CONDITION
- ADVANCED WINDOWS
AND DOORS
- AIR-TIGHTNESS LAYER
- CONTINUOUS INSULATION
PACKAGE
Retrofit Concept

81. EXIST.WALL
RETROFITWALL
20"
10 3/4"
51/2"
±91/4"
11/2"
91/4"7"
24"
+1'-8"
0'-0"
-0'-3"
+0'-0 1/2"
EXIST. ROOF FRAMING
TO BE DEMO'D
SNOW GUARDS PER MANUF.
INSECT SCREEN
VENT CHUTES
GUTTER
MAINTAIN CONT. AIR BARRIER W/ SIGA
BRAND TAPE AT SHEATHING TO TOP PLATE
MAINTAIN CONT. AIR BARRIER W/ SIGA
BRAND TAPE AT SHEATHING TO TOP PLATE
CONT. VENTING
BACKFILL
TYPICAL ABOVE GRADE RETROFIT (R-44)
ASSUMED EXISTING WALL ASSEMBLY
INTERIOR
• PLASTER
• WALLBOARD
• 2X4 FRAMING,
DENSE-PACK WITH CELLULOSE INSULATION (ADDED)
3.5 LBS/ CU FT
• EXTERIOR SHEATHING
RETROFIT WALL ASSEMBLY
• 5/8" OSB SHEATHING: SEAL JOINTS AIRTIGHT
VAPOR BARRIER, AIRTIGHTNESS LAYER
• 9-1/2" I-JOIST FURR FRAMING @ EXIST. STUDS WITH
DENSE-PACK CELLULOSE INSULATION, 3.5 LBS/ CU FT
• 1/2" FIBERBOARD SHEATHING (BILDRITE OR SIM.)
• WINDWASH BARRIER
WEATHER RESISTANT BARRIER
• 3/4" VENT SPACE (1X FRAMING)
• CEMENT BOARD LAP SIDING
EXTERIOR
TYPICAL BELOW GRADE RETROFIT (R-40)
INTERIOR
• 5/8" WALL BOARD
• 3-1/2" STEEL FRAMING @ 24" O.C. WITH
MIN. 2" CLOSED CELL SPRAY FOAM INSULATION
VAPOR BARRIER & AIRTIGHTNESS LAYER
• EXIST. CONCRETE WALL
• (2) 3" EXTERIOR GRADE EPS INSULATION (EIFS)
• STO FLEXYL (EIFS)
WEATHER RESISTANT BARRIER & FINISH
(TIE TO FACE OF FOOTING)
EXTERIOR
TYPICAL SLAB RETROFIT (R-25)
NOTE: REMOVE EXISTING SLAB & EXCAVATE TO
ACCOMODATE RETROFIT ASSEMBLY
INTERIOR
• 4" CONCRETE SLAB WITH
RADIANT IN-FLOOR HEATING SYSTEM
• 6-MIL POLY
VAPOR BARRIER & AIRTIGHTNESS LAYER
SEAL AIRTIGHT AT ALL JOINTS AND PROTRUSIONS
• 6" BELOW GRADE EPS INSULATION BOARD,
COMPRESSIVE STRENGTH PER SE
• MIN. 2" GRAVEL
EXTERIOR
TYPICAL VENTED COLD ROOF ASSEMBLY (R-77)
NOTE: REMOVE EXISTING ROOF STRUCTURE,
BUILD PERIMETER KNEE WALL AND SET NEW
TRUSSED HIP ROOF PER STRUCTURAL DRAWINGS
EXTERIOR
• STANDING SEAM METAL ROOFING @ 16" O.C.
• GRACE ICE & WATER SHIELD HT
ROOFING UNDERLAYMENT,
WEATHER RESISTANT BARRIER
• 3/4" PLYWOOD STRUCTURAL SHEATHING
• ATTIC AIRSPACE, OR VENT CHUTES
• STRUC. TRUSSES @ 24" O.C. WITH MIN.
20" CELLULOSE INSULATION
• 5/8" OSB SHEATHING, SEAL JOINTS AIRTIGHT
VAPOR BARRIER, AIRTIGHTNESS LAYER
• 6" INSTALLATION CAVITY WITH SUSPENSION
SYSTEM
• 5/8" WALLBOARD CEILING
INTERIOR
WEATHER RESISTANT BARRIER (WRB)
AIRTIGHTNESS LAYER & VAPOR RETARDER (AB & VR)
RETROFIT FRAMING
EXIST. WALL
TRUSSBEARING
2
10
T.O. KNEEWALL
T.O. EXISTING WALL
T.O. EXISTING R.O.
T.O. ADDITION R.O.s
CLEAR
@OUTSIDEOFSTUDWALL
7-1/2" TRIM
TYPICAL ABOVE GRADE WALL RETROFIT (R-44)
INTERIOR
• EXISTING WALLBOARD & FINISH
• EXISTING FRAMING WITH
3-1/2" DENSE PACK INSULATION, 3.5 LBS/ CU FT
• EXISTING SHEATHING
• 5/8" OSB SHEATHING: SEAL JOINTS AIRTIGHT
VAPOR BARRIER, AIRTIGHTNESS LAYER
• 9-1/2" I-JOIST FURR FRAMING @ 24 O.C. WITH
DENSE-PACK CELLULOSE INSULATION, 3.5 LBS/ CU FT
• 1/2" BUILDRITE SHEATHING
• WINDWASH BARRIER
WEATHER RESISTANT BARRIER
• 3/4" VENT SPACE (1X FRAMING)
• CEMENT BOARD LAP SIDING
EXTERIOR
CONTINUOUS 5/8" SHEATHING
CONNECTS EXISTING AND NEW CONSTRUCTION
VAPOR BARRIER & AIRTIGHTNESS LAYER
• Walls a/ grade: R-10 to R-44
• Walls b/ grade: R-1 to R-30+
• Roof: R-20 to R-77
• Slab: R-1 to R-25
Assemblies

82. 4"
4"51/2"
ROUGH OPENING
WINDOW SET POINT
OPT. 2X4
L-SECTION SILL END CAP
EXTERIOR ALUMINUM SILL
INTERIOR WOOD SILL
EPS FOAM STRIP
PLYWOOD STRIP
FILL VOID WITH EPS FOAM
8 7/8" (225 MM)
4" 5 1/2"
ROUGHOPENINGROUGHOPENING
EPS WEDGE
EPS INFILL
AIRTIGHT
CONNECTION
AIRTIGHT
CONNECTION
COMPRESSION
TAPE
DRIP EDGE
OPT. 2X4
L-SECTION
END CAP
3-1/2" TRIM
5-1/2"TRIM
7-1/4" TRIM
DC260
7" (180 MM)
ROUGHOPENING
AIRTIGHT
CONNECTION
TERRACE DOOR
SILL
L-SECTION
END CAP
COMPRESSION
TAPE
CRIPPLE WALL WITH
DENSEGLASS GOLD
SHEATHING
INT.JAMB
EXTENSION
EXT.JAMB
EXT. STEP
MIN.1-3/8"
1 3/4"
EXIST. ROUGH OPENING
WINDOW SET POINT
1" POLYISOCYANURATE FOAM BOARD
3/4" PLYWOOD BUCK
STO GUARD WET-FLASHING SYSTEM
STO FINISH PROFILE
AIR TIGHT CONNECTION
DOUBLE SIDED BUTYL TAPE
PER MANF.
RETROFIT ROUGH OPENING
REFERENCE DETAILS:
- STO W 425-1
- STO W 501
NOTE:
VERIFY DIMENSIONS
WITH ACTUAL PRODUCT
INTERIOR
EXTERIOR
8 7/8" (225 MM)
13/4"3/4"
STO FINISH PROFILE
STO DRIP EDGE
WINDOW R.O.
BLOCK R.O.
EXIST. R.O.
WINDOW R.O.
U-SECTION
END CAP
REFERENCE DETAILS:
- STO W 710
- STO W 425-2
SCALE: 3" = 1'-0"3
TYPICAL WINDOW JAMB
SCALE: 3" = 1'-0"2
TYPICAL WINDOW HEAD & SILL
SCALE: 3" = 1'-0"1
TYPICAL EXTERIOR WINDOW ELEVATION
SCALE: 3" = 1'-0"4
TYP. TERRACE DOOR SILL
SCALE: 3" = 1'-0"6
TYPICAL WINDOW JAMB, BASEMENT
SCALE: 3" = 1'-0"5
TYPICAL WINDOW HEAD & SILL, BASEMENT
WEATHER RESISTANT BARRIER (WRB)
AIRTIGHTNESS LAYER & VAPOR RETARDER (AB & VR)
Details

83. • Boiler (existing, replaced)
• In-floor heat (existing, reused and expanded)
• Ventilation system (new)
• Domestic hot water system (new plumbing)
MEP Systems

84. Construction Project

126. Rough-In Test
0.87 ACH50 [267 CFM50]≤1.0 Airtightness

143. Whole House Heat RecoveryVentilation

144. Insulated Tubes

145. Home-Run Distribution with Tubes

146. Installation/Service Cavities

147. Registers: Plug & Play

148. Heat Source: On-Demand Boiler (existing)

149. Unique Feature:Water Tree

150. Minisplit AC

151. The
Result

152. Photos: Spaces Magazine

156. Photos: Spaces MagazinePhotos: Spaces Magazine

157. Photos: Spaces Magazine

158. Photos: Spaces Magazine

159. Photos: Spaces Magazine

160. Photos: Spaces Magazine

161. Photos: Spaces Magazine

162. Photos: Spaces Magazine

163. Photos: Spaces Magazine

164. Photos: Spaces Magazine

165. Certified
Performance

166. Final Test
0.65 ACH50 [195 CFM50]≤1.0 Airtightness

167. Specific Primary Energy Demand
112 kWh/m2 a [35.5 kBTU/ft² a]
Component Approach
Minimum R-values throughout
Heating Load
20 W/m2 [6.3 Btu/h/ft²]
4.1 kW [14 kBtu/h]
≤130QP ≤ 120 kWh/m2a + ((QH - 15 kWh/(m2a)) * 1.2)
Airtightness
0.65 ACH50 [196 CFM50] ≤1.0
Cooling Load
2.6 kW
[0.74 tons, 8.8 kBtu/h]
Passive House Performance

168. Heat loss is dramatically reduced by more than 66%
over current new construction in Minnesota.
Passive House Comparison

169. Annual energy intensity was calculated at 16.5 kBTU/(sf yr).
This is a savings of 64% compared to a similarly-sized house meeting
MN 2015 residential energy code—modeled at 45.7 kBTU/(sf yr).
Passive House Comparison

170. Passive House Certification

171. • Structure ✓
• Weather Barrier ✓
• Insulation ✓
• Airtightness ✓
• Moisture Management ✓
• Ventilation/ Air Quality ✓
• Comfort ✓
• Daylight ✓
• Durability (50-100 years) ✓
• Design ✓
• Lifecycle Cost ✓
• Environmental Impact ✓
• Deconstructability ✓
HOLISTIC
DESIGN
}
Mission Accomplished!

173. Resources
passivehouse.com
passipedia.org
passivehouse-international.org

174. Thank you!
testudio.com