Over Deck Roof Insulation

The insulation installed over the roof deck must be installed in multiple layers with joints offset in order to control convective looping at joints between insulation panels.

Over deck roof insulation.

Can be used as a cover board in re roofing and new construction proven to reduce the tendency for blistering in hot asphalt applications. Add insulation above the roof deck this approach fits current building science thinking in terms of putting the thermal control layer on the outside of the building structure. Shed roofs project as a single plane roof pitched away from the house. The solid substrate for fluted metal decks is typically a gypsum underlayment and the concrete is the solid substrate for concrete decks.

How to install insulation board over an existing roof membrane 1. Densdeck roof boards are fm tested and approved as the only 1 2 gypsum product to meet the. If you are tying the roof directly to a house wall you can install a ledger board with flashing and install rafter ties to attach the rafters at the appropriate angles or use engineered trusses. The right thickness would need to be calculated to move the dew point above the plywood deck where air infiltration is minimized.

An excellent fire barrier densdeck roof boards feature a noncombustible core and inorganic surface that offer greater fire protection than other conventional commercial roofing products when applied over combustible roof decks and steel decks. On the gable ends this was pretty easy. See owens corning roofi ng systems guide specifi cations for details. Typically this would be achieved by adding polyiso insulation above the plywood deck.

For heat protection a cover board typically gypsum board must be adhered or mechanically fastened over the polystyrene roof insulation. One of the keys to over roofing is to tie the air control layer of the roof assembly to the air control layer of the wall assembly. Remove all existing flashing material from around vents and pipes using a pry bar and hammer. Bluish green foam insulation as over deck insulation and exterior wall insulation form a protective layer over the whole building.

The over deck insulation covers the roof and the columns from getting heated up and the wall insulation prevents the walls to be heated up. Flat roofs are more susceptible to leaking than pitched roofs. Roofs over concrete decks should always have a vapor barrier installed. Materials appropriate for insulating sheathing with unvented cladding substrate include.

Thermapink roof insulation can be used with bur or modifi ed bitumen systems. Concrete contains a significant amount of moisture and there is no test to accurately tell if the concrete is dry enough to install the roof on top of it. On the front of the roof edges the original roof deck sheathing was cut back flush with the wall and the fully adhered membrane folded down around the rafter tails to catch the. Like fully adhered insulation fully adhered vapor barriers need a solid substrate below.

Allows for installations directly over a wide flute or metal deck application for spans up to 2 and resists damage from construction and maintenance. The fully adhered membrane wrapped down over the cut back roof deck to tie into the wall water control layer and air control layer photograph 11. Insert the pry bar. Calculate the total square footage of the roof to determine the number of.