SECTION 1807.3.1

WALLS

Walls required to be waterproofed shall be of concrete or masonry and shall be designed and constructed to withstand the hydrostatic pressures and other lateral loads to which the walls will be subjected.

CODE INTERPRETATION

This section implies that all walls that require waterproofing shall be constructed of concrete or masonry and shall be of structural integrity to withstand hydrostatic pressure and lateral loads.

The waterproofing applied at the walls shall consist of one of the following membranes:

• Two-ply hot moped felts
• 6-mil+ polyvinyl chloride (PVC)
• 40-mil polymer modified asphalt
• 6-mil polyethylene

The waterproofing should be applied a minimum of 12 inches above the highest point of the ground water table. The membrane joints shall be lapped in accordance with the membrane manufacturers latest printed requirements.

DAMPPROOFING AND WATERPROOFING

SECTION 502.2.1

ROOF ASSEMBLY

The minimum thermal resistance (R-value) of the insulating material installed either between the roof framing or continuously on the roof assembly shall be as specified in Table 502.2(1), based on construction materials used in the roof assembly.

CODE INTERPRETATION

This code establishes the minimum R-value required for insulation above the deck on commercial buildings. The thermal R-value required for insulation applied entirely above the deck is based on climate zones in the chart listed below. The code indicates that the thermal R-value prescribed is for the insulation only and does not include other building materials or air films.

Building Envelope Requirements—Opaque Assemblies Roofs Insulation Entirely Above Deck

ROOFING

Building Enclosure  |  BuildingEnclosureOnline.com  |  Fall 2023

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