Par. 19. - All buildings and structures shall be calculated to resist a pressure per square foot on any vertical surface as follows: -

For forty feet in height, ....          Ten pounds.

Portions from forty to eighty feet above ground,.......Fifteen pounds.

Portions more than eighty feet above ground,.......Twenty pounds.

Wind Pressure

Par. 20. - But the commissioner may require a building or structure to be designed for larger pressure than the pressures given in the table, if, in his judgment, the exposure requires it.

Par. 21. - If the resisting moments of the materials of construction are not sufficient to resist the moment of distortion due to wind pressure without exceeding the stresses allowed in this act, additional bracing shall be introduced to supply the deficiency in the moment.

[1918, c. 179, sect. 16, Special Act.] [1914, c. 595.]

Section 37. Shutters

Par. 1. - In all first or second class mercantile or manufacturing buildings over thirty feet in height, outside openings in party walls, or in any rear or side wall within twenty feet of an opposite wall or building, shall have metal frames and sashes and shall be glazed with wire glass or shall be protected by shutters. Such shutters shall be covered on both sides with tin or shall be made of other substantial fireproof material, and hung on the outside, either upon independent metal frames or upon metal hinges attached to the masonry, and shall be made to be handled from the outside, and one such shutter in each room shall have a protected hand-hole eight inches in diameter.