Insulation and Infiltration

Building Shell

Air Barrier

3

Air Sealing

All homes must pass a blower door test with a result between 0.50 ACHn and 0.25 ACHn

4

• Create an airtight shell using wall sheathing and ceiling drywall.

• Fill cavities completely with insulation.

• Encapsulate insulation on all sides.

• Use required Energy Code R-values.

Good Building Envelope

Correct

Attic Kneewalls

9

Air Sealing

Bottom plate must be sealed to poured wall, slab, or subfloor.

Correct

Incorrect

10

Air Sealing

Soffits must be sealed at cantilevered floors.

11

Air Sealing

Exhaust fan penetrations must be sealed at the band joist.

Correct

12

Air Sealing

Joist cavities under attic kneewalls must be blocked.

Correct

13

Air Sealing

Penetrations through insulated floors must be sealed.

Correct

14

Air Sealing

HVAC boots in insulated floors must be sealed to the subfloor.

Correct

15

Air Sealing

Top and bottom plate penetrations must be sealed.

Correct

Correct

16

Air Sealing

Exterior doors must have weatherstripping, thresholds, and doorknobs prior to final inspection in order to pass (including basement doors if they penetrate the building envelope).

Correct

17

Air Sealing

Gaps between pieces of exterior sheathing must be sealed.

CorrectIncorrect

18

Air Sealing

Penetrations in exterior wall sheathing must be sealed.

Correct Correct

19

Air Sealing

Exterior walls of fireplace chase must be sealed (including combustion air inlet).

Incorrect

20

Air Sealing

Shower and tub drains must be sealed (rock wool/fiberglass not acceptable).

CorrectIncorrect

21

Air Sealing

Solid sheet must be installed behind tubs and showers on insulated walls.

Correct

22

Air Sealing

Window and door rough openings must be sealed (not chinked with insulation).

Correct

23

Air Sealing

Stud cavities at changes in ceiling height must be blocked.

Correct

24

Air Sealing

Attic kneewall doors must seal tight- this requires weatherstripping and a latch.

Correct

25

Air Sealing

Stud cavities blocked from attic – including attic kneewalls

Correct

26

Air Sealing

Attic kneewalls must be sheathed (and R-19 minimum insulation value).

Correct

27

Air Sealing

Chase caps and penetrations through chase caps must be sealed

Correct

28

Air Sealing

Chases must be capped.

CorrectIncorrect

29

Air Sealing

Recessed can lights in insulated ceilings must be air tight.

Correct

30

Air Sealing

Ceiling mounted electrical fixtures, including lights, ceiling fans, and speakers in insulated ceilings must be sealed to drywall.

Incorrect

31

Air Sealing

HVAC boots in insulated ceilings must be sealed to drywall.

Correct

32

Air Sealing

Attic scuttle holes must seal tight- this requires weatherstripping

Incorrect

33

Air Sealing

Attic pulldown stairs located in conditioned space must seal tight.

Correct Correct

34

Insulation

Basement foundation walls must be insulated to a minimum of R-5 if they are part of the building envelope.

35

Insulation

Concrete foundation walls may not be insulated with kraft-paper faced fiberglass batts. Unfaced batts, blown in fiberglass, or perforated vinyl encapsulated batts are permitted.

Note: Floors over an unconditioned basement can be insulated instead of foundation walls. When intending for the basement to be conditioned, you must plan for this in the load calculation or the equipment will be too small.

36

Insulation

Insulation must be installed against a solid air barrier (OSB, drywall, concrete, or solid sheet good).

Incorrect

37

Insulation

Wall insulation must fill cavities completely.

Correct

38

Insulation

Attic kneewalls must be a minimum R-19 insulation value

Correct

39

Insulation

All areas of the attic must have vent openings. Bonus rooms over the garage must be vented, in addition to the attic.

Correct

40

Insulation

Blown attic insulation may not block soffit vents - baffles must be used

Correct

Incorrect

41

Insulation

Blown attic insulation must have rulers and an attic card in each accessible attic space

Correct

42

Moisture and Indoor Air Quality

No polyethylene is allowed in above or below grade wall assemblies (except behind tubs and showers in bathrooms)

43

Moisture and Indoor Air Quality

All fireplaces and other combustion equipment must be equipped with a flue and outside combustion air supply.

No ventless fireplaces are allowed.

Correct

44

Insulation

Limit the number of 4x8 sheets of subfloor installed in the attic. (If more than two sheets of subfloor is desired, it is recommended they be raised up to provide for the full attic height of insulation underneath.)

Building Shell

Air Barrier

Air That Has Been Heated, Rises.

As the air inside the envelope is heated, it begins to rise.

Air That Has Been Heated, Rises.

The Air will escape through any available hole.

Air That Has Been Heated, Rises.

COMMON HOLESBathroom Fans and Wiring/Plumbing penetrations

Air That Has Been Heated, Rises.

As air leaves the envelope, it creates aNegative (pulling) pressure.

Air That Has Been Heated, Rises.

Outside air is drawn into the home to replace the escaping warm air.

Air That Has Been Heated, Rises.

The cold outside air is then heated. As the air is heated it rises.

Air That Has Been Heated, Rises.

The cycle is repeated.