Sarking in roof constructions
The term ‘sarking’ can have a number of different meanings relating to roof construction.
Sarking boards are typically softwood boards that are attached to the rafters of a pitched roof, below the roof-covering. They are typically around 150 mm wide and are used to provide additional support and strength to the overall structure.
They are used on buildings that can be exposed to high winds, heavy rain or other extreme weather conditions. As a result, they are more common in Scotland than in England or Wales. Boards tend to only be specified for new-build, not refurbishments, as this would entail a complete re-roofing with coverings being removed and replaced, and potentially exceeding the load-carrying capacity of the roof structure.
A typical roof build-up that contains sarking is as follows (from the bottom):
- Insulation (sitting either between-and-under or between-and-over the rafters).
- Sarking boards (with a gap of 2-3 mm between each one).
- Breathable membrane.
- Roof tiles or other covering.
The term 'sarking' can also refer to a pliable membrane such as a layer of felt, polystyrene or reflective foil, that insulates or reflects heat and can provide extra weather resistance. It can act as a protective second skin for the roof by helping to prevent storm-driven rain penetrating into the roof cavity. By helping to reduce draughts, it can also limit dust entering the building through gaps around downlights and vents, and help improve thermal performance.
[edit] Find out more
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Introducing or next Guest Editor Arun Baybars
Practising architect and design panel review member.
Quick summary by size, shape, test, material, use or bonding.
Types of rapidly renewable content
From forestry to agricultural crops and their by-products.
Terraced houses and the public realm
The discernible difference between the public realm of detached housing and of terraced housing.
Put digitalisation and sustainability at the core of curricula
Project management educators are urged.
Looking back at the influence of climate events
From a designer and writer: 'There are limits to growth but no limits to development'.
Terms, histories, theories and practice.
Biophilic design and natural light
Letting in the light and natural elements into spaces.
APM Programme Management Conference 2024
Strategies for Success.
Residential takes the reins as contract awards even out
Contracts down, but remain above the last quarter of 2023.
Celebrating Eid and the largest mud-brick building.
Barry Kingscote claims prestigious CIOB CMYA Award.
The British Mosque: an architectural and social history
The story of some 1,500 mosques or more in Britain.
Heat pump refrigerants, efficiencies and impacts
R12 to R1270 what are the differences?
Global heat pump market in 2023
Challenging times with positive but modest outlook.
Beyond the infrastructure pipeline
Opportunities and chokepoints.