Cold Roof Build Up

Plywood boards must be at least 18mm thick and of exterior grade.

Cold roof build up.

When warm damp air permeates up through the ceiling and reaches the cold roof space the change in temperature can result in condensation forming. However cold roof insulation on an existing flat roof system is anything but simple. In this video i explain three different ways of building a flat roof using the war. They help prevent wood rot and can prevent ice dam.

Such a roof paired with a boston ridge vent prevents ice damming and roof leaks. The scenario for a leaky conventional roof in snow country goes like this. Ice dams happen for a number of rea sons but mostly they involve insufficient insulation or poor roof venting. The snowmelt runs down the roof beneath the accumulated snow refreezes when it hits the cold air at the eaves and blocks the flow causing an ice buildup and often a leak.

I m often asked what the difference is between a warm roof and cold roof. Stop ice dams with a cold roof. It requires the existing roof surface to be ripped up so that the insulation can be laid in between before a new roof surface is then placed over the top. The ice traps meltwater which can seep back up under shingles and drip through the roof into your house causing wet and stained ceilings and walls and peeling paint and rot.

The wooden rafters conduct heat much more than insulation which means you end up with something called thermal bridging. With temperatures below freezing snow accumulates on the roof over a vaulted ceiling. All the substrates must be flat dry and sufficiently resistant to stress e g. I also learned to build what s known as a cold roof.

The vcl in a cold roof construction. Should the ceiling below also have downlighters the vcl could be seriously damaged and therefore virtually useless. Typically roofs with terrains of 10 to 20 are often referred to as low pitched roofs. In a cold roof build up the vcl normally ends up on the underside of the joists or rafters and is punctured many times when covered over by the internal finishes.

Cold roof insulation is most commonly used when a flat roof is first being created because it s a relatively easy process. Water running down the roof refreezes when it reaches the colder roof edge forming a mound of ice. A cold roof is roof in which the thermal insulation layer is located between the ceiling joists meaning that everything above the insulation such as the rafters and any roof space will be colder than the living space below it. Cold roof on vented plywood.