Pitched Roof Insulation Ventilation

If you choose to vent the roof deck then be serious about it and really vent it.

Pitched roof insulation ventilation.

Insulating a pitched roof in a pitched roof insulation is usually introduced in one of three areas. A cold roof is the most common type of roof construction often taking the form of an uninhabited storage space. Above the rafters so the whole roof structure is warm below and between the rafters so the roof space itself is warm or between and above the ceiling joists the cold roof option. With summer approaching and temperatures rising now would be the perfect time to consider adding some insulation to your roof which is a part of the construction under the direct influence of the weather conditions read steaming sun rays that can be ruthless when the summer season is at its peak.

If the roof covering or roof membrane is a material of high moisture resistance or impermeable then the building regulations require a 50mm wide ventilation gap beneath the roofing felt and tiles. Warm pitched roof to create a warm pitched roof insulation such as kingspan kooltherm k7 pitched roof board should be fitted between and over the rafters. Regulation ventilation and insulation of pitched roofs. Fabrications with 3mm 10mm openings are acceptable.

As this requires fitting insulation above the rafters the roof covering will have to be removed in order to fit the insulation. The minimum requirements for cold roof ventilation are set out in bs 5250 control of condensation in buildings which takes into consideration span pitch and roof area. Eaves soffits and fascias. Slating and tiling for pitched roofs and vertical cladding code of practice recommends that roof ventilation be provided in accordance with bs 5250.

Bs 5250 sets out the minimum requirements for roof space ventilation. The code calls for a minimum of 1 in. To provide ventilation opening points can usually be provided on the following areas of a pitched roof. Ventilation openings should prevent the entry of birds etc.

For example in the average house with a cold loft there should be a minimum of a 7mm continuous ventilation gap at eaves when using a vapour permeable underlay with a normal unsealed ceiling. A roof void above an insulated ceiling. Of airspace between the top of the insulation and the back of the roof sheathing. To provide adequate ventilation and to avoid condensation in roof voids pitched roofs that have insulation at ceiling level should be ventilated to the outside air.