jabacus - Snow Load Calculator

Roof Snow Load

(NBC 2020)

v1.0.0

Location

Province:

Ground snow load

S_s:

Rain Load

S_r:

Importance Factor, I_s:

Basic Roof Factor, C_b:

If C_b left blank, provide the dimensions in the roof geometry to compute C_b

Wind Factor, C_w:

Accumulation Factor, C_a:

(If C_aleft blank, C_a will be computed assuming gable roof)

Roof Geometry

Pitch:

/12

Slippery:

Roof Plan dimensions

Dimensions used to calculated C_b if C_b left empty.

Longer dimension, l:

Shorter dimension, w:

[4.1.6.2]

S = I_s[S_s(C_bC_wC_sC_a)+S_r]

User input values:

Ss = 1 kPa

Sr = 1 kPa

Importance Factors:

ULS: I_s = 0.8

SLS: I_s = 0.9

C_b = 0.8 (based on input C_b
Roof slope = 0 degrees
Slope Factor

For non-slippery roof:
Slope <= 30 degrees: C_s = 1

[Table A-4.1.6.9]

Same load on both upwind and downwind sides.

ULS:
C_w = 1
C_a = 1

SLS:
C_w = 1
C_a = 1
S = 1.62 kPa ( 33.8 psf )

Load Case II does not apply to gable roofs with slopes of 15 degrees or less.

This information must be read or used in conjunction with Part 4 of the NBC 2020. In the event of discrepancies, Part 4 of the NBC 2020 shall govern.