This document summarizes the key aspects of a holistic design for a sustainable home retrofit project. The retrofit aims to improve the structure, weather barrier, insulation, air tightness, moisture management, ventilation, comfort, daylighting, durability, design, lifecycle costs, environmental impact, and deconstructability of the home. Schematic designs and typical assembly details are provided to illustrate the proposed envelope upgrades, including high performance walls, roof, slab, and basement designs. Performance targets for heating loads, efficiency, and air tightness are also listed.

1. holistic design for
sustainable homes
• comfort
• economy
• ecology
• quality
• durability
• beauty
• functionality
• health
STUDIO:
3429 Benjamin St. NE
Minneapolis, MN 55418
612-246-4670
testudio.com
CERTIFIED PASSIVE HOUSE™ CONSULTANT

3. 1935

4. What were they thinking?
Structure ✓
}
•
• Weather Barrier ?
• Insulation ✗
• Airtightness ✗
• Moisture Management ✓
• Ventilation/ Air Quality ✗ GIT-R DONE
• Comfort ✗ ✗
• Daylight ✗
• Durability (30 years?)
• Design (Sign of the Times)

5. Where are we?

10. • 2 stories + basement
• 1,200 finished SF
• 2 bedrooms
• 1 bath
• 5 people

15. Envelope

16. Windows

17. Airtightness
8.5 ACH50 [2,100 CFM50]

18. Mechanical systems

19. Mechanical systems

20. Where do we go?

21. Laundry List
• + 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

23. How do we get there?

24. Sports car?

25. Holistic Approach
• 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
• Design robust climate zone-appropriate assemblies

26. Basic
Concept

27. Schematic
DEEP ENERGY REDUCTION RETROFIT (AFTER) TYPICAL EXISTING BUILDING (BEFORE)
OPTIONAL SOLAR THERMAL
OR SOLAR PHOTOVOLTAIC
SO ADIN R)
SH MM
LA
(SU
SUPPLY AIR
R
G
E
PAS
SIVE
HEA S
T GA OLAR
(WIN IN
TER S EXTRACT AIR
)
RETROFIT CONDITION EXISTING CONDITION
INTERNAL
- ADVANCED WINDOWS - INSUFFICIENT INSULATION
HEAT GAINS
AND DOORS - LOW-PERFORMANCE
- PEOPLE
- AIR-TIGHTNESS LAYER WINDOWS AND DOORS
- EQUIPMT.
- CONTINUOUS INSULATION - AIR LEAKAGE
PACKAGE - NO VENTILATION
EXHAUST
AIR-INTAKE
RETROFIT CONDITION EXISTING CONDITION
HEAT-RECOVERY LARGE "ACTIVE"
- WATER PROOFING - NO WATER PROOFING
VENTILATION & MECHANICAL SYSTEM
AND MANAGEMENT AND MANAGEMENT
SMALL HEATER - FURNACE OR BOILER
- ADDED INSULATION - NO INSULATION AT AND
- MITIGATION OF BELOW GRADE
THERMAL BRIDGES - THERMAL BRIDGES

28. First Floor Plan
1. Entry
2. Powder room
3. Mud room/ laundry
4. Living room
DN
8 1 2 3 9 5. Kitchen
6. Dining area
7. Family area
UP DN
8. Covered entry
DN
9. Rear entry
10.Patio
6 10
4 5
7
N
0 2' 4' 8'

29. Basement Floor Plan
1. Homeschool Room
2. Mechanical
3. Unexcavated
3
UP
1 2 3

30. Second Floor Plan
1. Bedroom 1
2. Bedroom 2
3. Master BR
1 4. Master Clo.
5. Master Bath
6. Bedroom 3
7. Kid’s Bath
8. Toilet Room
2
7
8
6 4 3
5 7

31. TYPICAL VENTED COLD ROOF ASSEMBLY (R-77)
TRUSS BEARING
Typical
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,
Assemblies
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
@ OUTSIDE OF STUDWALL
• Walls a/ grade: R-44 SNOW GUARDS PER MANUF.
20"
MAINTAIN CONT. AIR BARRIER W/ SIGA VENT CHUTES
BRAND TAPE AT SHEATHING TO TOP PLATE
• Walls b/ grade: R-30+ 10 3/4"
2
T.O. KNEEWALL
+1'-8"
CLEAR
10
5 1/2"
• Roof: R-77
7"
CONT. VENTING
GUTTER
EXIST. ROOF FRAMING 24"
TO BE DEMO'D
9 1/4"
• Slab: R-25 MAINTAIN CONT. AIR BARRIER W/ SIGA
BRAND TAPE AT SHEATHING TO TOP PLATE
1 1/2"
T.O. ADDITION R.O.s
+0'-0 1/2"
RETROFIT FRAMING
T.O. EXISTING WALL
0'-0"
EXIST. WALL T.O. EXISTING R.O.
± 9 1/4"
-0'-3"
RETROFIT WALL
EXIST. WALL
TYPICAL ABOVE GRADE WALL RETROFIT (R-44)
INTERIOR
• EXISTING WALLBOARD & FINISH TYPICAL ABOVE GRADE RETROFIT (R-44)
• EXISTING FRAMING WITH
3-1/2" DENSE PACK INSULATION, 3.5 LBS/ CU FT ASSUMED EXISTING WALL ASSEMBLY
• EXISTING SHEATHING INTERIOR
• 5/8" OSB SHEATHING: SEAL JOINTS AIRTIGHT • PLASTER
VAPOR BARRIER, AIRTIGHTNESS LAYER • WALLBOARD
• 9-1/2" I-JOIST FURR FRAMING @ 24 O.C. WITH • 2X4 FRAMING,
DENSE-PACK CELLULOSE INSULATION, 3.5 LBS/ CU FT DENSE-PACK WITH CELLULOSE INSULATION (ADDED)
• 1/2" BUILDRITE SHEATHING 3.5 LBS/ CU FT
• WINDWASH BARRIER • EXTERIOR SHEATHING
WEATHER RESISTANT BARRIER
• 3/4" VENT SPACE (1X FRAMING) RETROFIT WALL ASSEMBLY
• CEMENT BOARD LAP SIDING • 5/8" OSB SHEATHING: SEAL JOINTS AIRTIGHT
EXTERIOR VAPOR BARRIER, AIRTIGHTNESS LAYER
CONTINUOUS 5/8" SHEATHING • 9-1/2" I-JOIST FURR FRAMING @ EXIST. STUDS WITH
CONNECTS EXISTING AND NEW CONSTRUCTION DENSE-PACK CELLULOSE INSULATION, 3.5 LBS/ CU FT
VAPOR BARRIER & AIRTIGHTNESS LAYER WEATHER RESISTANT BARRIER (WRB) • 1/2" FIBERBOARD SHEATHING (BILDRITE OR SIM.)
AIRTIGHTNESS LAYER & VAPOR RETARDER (AB & VR) • WINDWASH BARRIER
WEATHER RESISTANT BARRIER
• 3/4" VENT SPACE (1X FRAMING)
• CEMENT BOARD LAP SIDING
EXTERIOR
INSECT SCREEN
7-1/2" TRIM
BACKFILL
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
TYPICAL BELOW GRADE RETROFIT (R-40)
VAPOR BARRIER & AIRTIGHTNESS LAYER
SEAL AIRTIGHT AT ALL JOINTS AND PROTRUSIONS INTERIOR
• 6" BELOW GRADE EPS INSULATION BOARD, • 5/8" WALL BOARD
COMPRESSIVE STRENGTH PER SE • 3-1/2" STEEL FRAMING @ 24" O.C. WITH
• MIN. 2" GRAVEL MIN. 2" CLOSED CELL SPRAY FOAM INSULATION
EXTERIOR 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

32. Value Engineering
Hea$ng'Transmi$on'Losses'
2%$
Walls$a/g$
34%$ Walls$b/g$
32%$
Roof$
Slab$
Windows$
7%$
15%$ Doors$
10%$

33. Energy Balance
Hea)ng&Energy&Use&vs.&Input&
12000.00#
10000.00#
Ac7ve#Hea7ng#
8000.00#
Internal#Gains#
kWh/a&
6000.00#
Solar#Gains#
4000.00# Ven7la7on#Losses#
2000.00# Transmission#Losses#
0.00#
Losses#in#kWh/a# Gains#in#kWh/a#

34. Performance Numbers
Specific Space Heat Demand:
24 kWh/m2 a [7.6 kBTU/ft² a]
Heating Load:
19 W/m2 [6.0 Btu/h/ft²]
≤25
≤130.8
3.75 kW [12.8 kBtu]
Specific Primary Energy Demand:
115 kWh/m2 a [36.5 kBTU/ft² a]
QP ≤ 120 kWh/m2a + ((QH - 15 kWh/(m2a)) * 1.2)

35. Mechanical Response

36. What does it all look like?

60. ≤1.0 Airtightness
0.88 ACH50 [267 CFM50]

62. 2011

63. What are we thinking?
}
• Structure ✓
• Weather Barrier ✓
• Insulation ✓
• Airtightness ✓
• Moisture Management ✓
• Ventilation/ Air Quality ✓
• Comfort ✓
HOLISTIC
• Daylight ✓
DESIGN
• Durability (50-100 years) ✓
• Design ✓
• Lifecycle Cost ✓
• Environmental Impact ✓
• Deconstructability ✓

65. Thank you!
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