Is a warm roof better than a cold roof?
A warm deck roof can be very simple to install and offers higher thermal performance at the cost of a higher roof profile. Warm roof insulation ensures the entire roof structure is insulated, meaning a warm deck roof is more energy efficient than a cold roof.
What is cold deck roof?
The insulation in a cold deck roof is installed at ceiling level, therefore the void is at a colder temperature than the room below during colder weather. This poses a risk of condensation forming within the void or on the underside of the roof slab.
Can you turn a cold roof into a warm roof?
Cold bridging occurs when there is a continuous path created through the insulation. If an existing cold roof is to be refurbished, consideration should be given to converting the design to a warm roof, or incorporating new insulation into the roofing system to improve thermal performance.
Does a warm deck roof need ventilation?
Warm Deck – this is where the insulation is placed on top of the rafters/joists and the roof covering is then placed over the insulation. No ventilation is required for these types of roofs.
Do I need to ventilate a cold roof?
Cold Roofs A cold roof is where all of the insulation is placed either between and under or completely under the joists or deck. No insulation is on top. In this way the roof itself is kept cold. You only need ventilation in a cold roof.
Do you need ventilation in a cold roof?
Does cold roof need ventilation?
Do you need a Vapour barrier on a cold roof?
Wrong! sadly, it’s often the way – out of sight, out of mind, but the humble VCL is actually a very important part of the roof build-up. Be it a cold or warm roof construction, the primary function of a VCL is to keep warm moist air from inside the building – inside the building.
Do you have to vent a warm roof?
A warm flat roof usually does not require ventilation. What space do I need to allow for the ventilation? To ensure sufficient ventilation, enough space must be provided to allow for the movement of air, preventing the risk of condensation forming within the roof.
Which is better a cold deck or warm deck flat roof?
For most domestic purposes a warm deck flat roof is superior to a cold deck. Converting a cold flat roof into a modern warm deck roof can be surprisingly economical. Provided the existing roof is in a good state of repair and has a suitable structure a warm deck overlay can be applied.
Where is the insulation in a warm deck roof?
This was the traditional way of flat roof construction and as insulation has increased over the years, the warm deck roof is now the commonly used method of construction. The insulation in a warm deck roof is installed immediately below the roof membrane on top of the roof deck, usually with a vapour control layer underneath the insulation.
Can a cold deck roof cause condensation?
The insulation in a cold deck roof is installed at ceiling level, therefore the void is at a colder temperature than the room below during colder weather. This poses a risk of condensation forming within the void or on the underside of the roof slab.
What are the drawbacks of a cold roof?
Heat loss is the major drawback of cold roofs since you have to compensate for it with a heating system. The cost of regulating the temperature in a home with a cold roof far exceeds that of a warm roof. Constructing a cold roof on an existing roof can be challenging and time-consuming.