Sarking boards with a gap of 2 3 mm between each one.
Sarking board roof detail.
The purpose of the anti ponding board is to prevent water from pooling underneath the tiles at the outer edge of the roof.
Putting on the tiles.
The use of bituminous under slate felt or other vapour barriers under the slates which prevent water vapour movement can lead to high humidity in the roof space and can have detrimental effects on the roof in the long term.
Insulation sitting either between and under or between and over the rafters.
An entire re roofing process would need to take place to add sarking boards where any roof tiles or slates would need to be removed and then replaced over the top.
Hi all our roof will be metal raised seam it is supposed to sit on 18mm osb which i don t plan on doing i m planning on using a sarking board just like our scottish neighbours do would you use treated timber or just rough sawn.
Next anti ponding board apb is installed underneath the sarking at the edges of the roof.
Tiles are then laid out.
Roof sarking improves performance and comfort by providing the following benefits.
Underneath these battens you will find your counter battens running vertically and beneath these a breather membrane.
Product will differ from image slightly as it is rough sawn.
A sealed roof system is achievable using a vapour permeable underlay such as monarperm 700 if a minimum 2mm gap can be guaranteed between the sarking boards which should be a minimum of 150mm wide.
I have two views on this but thought i would get a collective opinion.
A typical roof build up that contains sarking is as follows from the bottom.
So now that we ve established where more often than not scotland and when during new build or re roofing projects you need to use sarking boards let s take a look at a typical roof build up.
If the sarking boards are damaged and require renewal they should be re laid with a small gap to allow for ventilation.
The sarking board itself is a barrier to the migration of water vapour and in most situations will require the provision of ventilation to the roof space in accordance with bs5534 bs5250 2011.
The apb effectively extends the barrier provided by sarking out to the guttering.
Helps protect your home from unseen mould growth or even worse ceiling staining or permanent damage which can result from the entry of storm driven rain into the roof cavity.
Roof tiles or other covering.
