Unvented Metal Roof Detail

In unvented flat or low slope roofs with parapets perform a full flood test to ensure leak free installation of roofing membrane.

Unvented metal roof detail. Roof pitch the metal roofing panels shown in this manual require a mini mum slope of 2 per foot to ensure proper drainage. Unvented roofs vented roof. Deck w iso details. Enhancing roofing material life span by reducing sheathing temperature.

For longer slopes and lower roof pitches contact fabral for other suitable profiles. Refer to the rain carrying table in this booklet for the maximum allowable panel length per slope that will provide adequate drainage. Tommy johnson pe engineering manager at mcelroy metal says unvented in and of itself. Drying of unvented roofing assemblies is by definition only provided to the interior.

Rake to metal wall detail. Metal cladding manufacturers warranties may be unaffected by whether a roof is vented or unvented as is the case for bossier city la based mcelroy metal s warranty. Test roofing membranes for integrity prior to covering from below. These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck.

Controlling ice damming by keeping the roof cold. An unvented assembly can perform well but it s important to get the details right to avoid sheathing rot. Removing moisture from roof cavities structural members sheathing and insulation. There are traditionally four main reasons for venting a roof.

Cad details document name pdf dwg download all cad construction details 37 1 mb 3 4 mb mc01 identification of roof areas 694 kb 167 kb mc01a single layer underlayment 678 kb 302 kb mc01b double layer underlayment 711 kb 322 kb mc02 vent pipe flashing 626 kb 349 kb mc03 valley. Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction. Air permeable insulation such as fiberglass batts dense packed cellulose or blown in fiberglass can t be used alone for an unvented assembly since these types of insulation can allow moist indoor air to reach the cold roof sheathing leading to condensation or moisture accumulation. Unvented metal roof assemblies are common on warehouses factories and shopping malls.