Usually this construction is a ventilated roof which will have sarking felt.
Pitched roof sarking insulation.
For pitched roofs below 20 degrees with a slate or tile covering the roof build up is the same as for the steeper pitches but all of the joints of the wood fibre sarking boards must be taped or sealed to prevent water penetrating the joints.
What is roof sarking.
7 2 14 underlay and sarking.
Roof sarking is an thin insulating membrane that helps protect the roof space from water and dust.
Unilin offers sarking as solution for insulating your pitched roof.
Sarking and the building code of australia.
It is mandatory under the building code of australia bca that all tiled residential roofs regardless of roof pitch with a rafter length greater than 6 metres must be sarked.
Ventilated roofs require a 50 mm air gap above the insulation.
To create a warm pitched roof insulation such as kingspan kooltherm k7 pitched roof board should be fitted between and over the rafters.
Csr recommends that all tiled roofs with a pitch of less than 20 are sarked and the bca mandates this requirement for rafter lengths greater than 4 5 metres.
The great advantage compared to insulating from the inside is the uninterrupted insulation shield and the exclusion of thermal bridges.
A house roof is a fairly complicated structure made up of joist battens trusses and the roof cover such as corrugated sheet metal.
Sarking boards are softwood boards generally about 150 mm wide that are attached to the rafters of a pitched roof to give extra strength to the overall structure of a building.
7 2 15 ventilation vapour control and insulation.
They needn t be used in every application and instead their use largely depends on where in the country you are based and what type of construction you are building.
Pitched roofs that have insulation at ceiling level should be ventilated to the outside air.
Insulation pitched roof once you understand that 30 of a building s heat is lost via the roof which does nothing at all to help your home s energy level you realise why it makes sense to focus first on the subject of roof insulation.