This is from Ontario building code Division B part 4:
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4.1.6.2. Specified Snow Load (See Appendix A.)
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(4) For buildings in the Low and Normal Importance Categories as set out in Table 4.1.2.1.B., the wind exposure factor
given in Sentence (3) may be reduced to 0.75 in rural areas, or to 0.5 in exposed areas north of the treeline, where,
(a) the building is exposed on all sides to wind over open terrain as defined in Clause 4.1.7.3.(5)(a), and is expected to
remain so during its life,
(b) the area of roof under consideration is exposed to the wind on all sides with no significant obstructions on the roof,
such as parapet walls, within a distance of at least 10 times the difference between the height of the obstruction and
CbCwSs/γ metres, where γ is the unit weight of snow on roofs as specified in Article 4.1.6.13., and
(c) the loading does not involve the accumulation of snow due to drifting from adjacent surfaces.
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Questions: how to find out if a municipal location is north of the treeline?
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4.1.6.2. Specified Snow Load (See Appendix A.)
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(4) For buildings in the Low and Normal Importance Categories as set out in Table 4.1.2.1.B., the wind exposure factor
given in Sentence (3) may be reduced to 0.75 in rural areas, or to 0.5 in exposed areas north of the treeline, where,
(a) the building is exposed on all sides to wind over open terrain as defined in Clause 4.1.7.3.(5)(a), and is expected to
remain so during its life,
(b) the area of roof under consideration is exposed to the wind on all sides with no significant obstructions on the roof,
such as parapet walls, within a distance of at least 10 times the difference between the height of the obstruction and
CbCwSs/γ metres, where γ is the unit weight of snow on roofs as specified in Article 4.1.6.13., and
(c) the loading does not involve the accumulation of snow due to drifting from adjacent surfaces.
....
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Questions: how to find out if a municipal location is north of the treeline?
