NH Carpenter Building Codes

Question 1

What version of the IRC is adopted in NH (as of 2024)?

Answer 1

2018 IRC with NH Amendments

Question 2

What code governs existing buildings in NH?

Answer 2

2018 IEBC with NH Amendments

Question 3

What code governs energy requirements in NH?

Answer 3

2018 IECC

Question 4

What is the minimum ceiling height for habitable spaces?

Answer 4

7 feet (IRC R305.1)

Question 5

What is the maximum stair riser height?

Answer 5

7 3/4 inches (IRC R311.7.5.1)

Question 6

What is the minimum stair tread depth?

Answer 6

10 inches (IRC R311.7.5.2)

Question 7

Minimum headroom for stairs?

Answer 7

6’ 8” (IRC R311.7.2)

Question 8

Minimum hall width?

Answer 8

3 feet (IRC R311.6)

Question 9

Minimum egress window net clear opening?

Answer 9

5.7 sq ft above grade; 5.0 sq ft at grade (IRC R310)

Question 10

Minimum egress window opening height?

Answer 10

24 inches (IRC R310)

Question 11

Minimum egress window opening width?

Answer 11

20 inches (IRC R310)

Question 12

Minimum guard height on decks?

Answer 12

36 inches (IRC R312.1.2)

Question 13

Guard required when drop exceeds?

Answer 13

30 inches (IRC R312.1.1)

Question 14

Minimum handrail height?

Answer 14

34–38 inches (IRC R311.7.8.1)

Question 15

Handrail required when?

Answer 15

Four or more risers (IRC R311.7.8)

Question 16

Required landing at exterior doors?

Answer 16

Yes, except small exceptions (IRC R311.3)

Question 17

Maximum spacing for balusters?

Answer 17

4 inches (IRC R312.1.3)

Question 18

Snow load in NH?

Answer 18

Based on town-specific maps; typically 50–70 psf or higher

Question 19

Deck ledger attachment requirement?

Answer 19

Must be through-bolted or lagged into rim per R507

Question 20

Fastener requirements for treated lumber?

Answer 20

Must be corrosion-resistant (IRC R317.3)

Question 21

Minimum footing depth in NH?

Answer 21

48 inches typical (frost depth)

Question 22

Notching limit for studs (load-bearing)?

Answer 22

25% of width (IRC R602.6)

Question 23

Boring limit for studs?

Answer 23

40% non-load-bearing, 60% with reinforcement (IRC R602.6)

Question 24

Joist bearing requirement?

Answer 24

1.5 inches on wood or steel (R502.6)

Question 25

Double top plate required?

Answer 25

Yes in most load-bearing walls (IRC R602.3.2)

Question 26

Header size reference?

Answer 26

IRC Table R602.7

Question 27

Fire blocking required at?

Answer 27

Floor levels, concealed spaces, intersection of soffits (IRC R302.11)

Question 28

Draft stopping required when?

Answer 28

Ceiling space exceeds 3,000 sq ft (IRC R302.12)

Question 29

Bathroom exhaust requirement?

Answer 29

50 CFM intermittent or 20 CFM continuous (IRC M1505)

Question 30

Rim joist insulation requirement?

Answer 30

R-20 or R-13 + R-5 continuous (IECC climate zone 5/6)

Question 31

Attic insulation minimum?

Answer 31

R-49 in zone 5/6 (IECC)

Question 32

Wall insulation minimum?

Answer 32

R-20 or R-13 + R-5 continuous (IECC)

Question 33

Floor insulation over unheated space?

Answer 33

R-30 (IECC)

Question 34

Slab insulation requirement?

Answer 34

R-10 for 2 ft (IECC)

Question 35

Window U-factor max?

Answer 35

0.32 (IECC zone 5/6)

Question 36

Door U-factor max?

Answer 36

0.32 for glazed doors

Question 37

What governs vapor barriers?

Answer 37

IECC & IRC R702.7

Question 38

Basement egress required when?

Answer 38

New bedrooms or finished spaces require IRC R310 compliance

Question 39

Fire separation between garage/house?

Answer 39

1/2" drywall; 5/8" on supporting structures (IRC R302.6)

Question 40

Minimum distance from siding to grade?

Answer 40

6 inches (IRC R317)

Question 41

Sill plate anchoring requirement?

Answer 41

Anchor bolts 1/2" diameter, 7" embed, 6 ft O.C. (IRC R403.1.6)

Question 42

When must smoke alarms be hardwired?

Answer 42

New construction; major remodels (IRC R314)

Question 43

CO detectors required?

Answer 43

Yes, outside sleeping areas (IRC R315)

Question 44

Minimum attic access opening?

Answer 44

22" × 30" (IRC R807.1)

Question 45

Roof sheathing nailing schedule?

Answer 45

6" O.C. edges, 12" O.C. field (IRC Table R602.3)

Question 46

Wall sheathing nailing schedule?

Answer 46

6" perimeter, 12" field unless engineered

Question 47

Deck post size minimum?

Answer 47

6x6 for heights over 8 ft (IRC R507)

Question 48

Lateral deck load connectors required?

Answer 48

Yes, 1,500 lb devices per IRC R507.9