Warm Flat Roof Ventilation

25mm at eaves on each slope and 5mm at ridge.

Warm flat roof ventilation.

Make sure your comply with flat roof building regulations. There s just enough ventilation to pull warm moist interior air through ceiling cracks. Once the moist air is in the tiny attic the moisture accumulates in the cold roof sheathing. The roof insulation in the cold roof is between.

Ventilation is not needed in a warm roof. This depends based on climate building type size residential or commercial. There are two types of flat roof systems warm and cold roofs which affect the positioning of the ventilation. Warm roofs are recommended for homes.

If ridge or eaves ventilation is not possible ventilation tiles can be used at high or low level to achieve the required airflow. For guidance on roof insulation please contact us on 44 01257 488 000. If you have a hot roof this warm air changes the temperature of your roof decking as it isn t protected by insulation. Find warm flat roof cold flat roof insulation solutions at iko polymeric.

The roof itself is therefore kept warm. This animated sketch up model shows the position of roof insulation in a warm roof and also in a cold roof. When thermal insulation is placed below the deck the ventilation must also be on the underside. The result is rot and mold.

The insulation is applied above the roof deck with waterproofing on top which eliminates the need for ventilation and keeps the roof warm. A warm deck roof is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation. Warm air rises and will naturally collect in your home beneath the roof. The ceilings leak air and the attic ventilation is inadequate.

By majority the rule of thumb is that in a domestic house not flats approximately a third of the total thermal performance of insulation can be placed below the deck with two thirds above the deck sometimes this is called a hybrid warm roof. How much ventilation is needed is not a set answer. Cold flat roofs are more common as on ad on and new constructions typically have the superior warm flat roof where the ventilation is above the deck but below the outer materials.