Wall plug
![]() |
Contents |
[edit] Outline
A wall plug (commonly called a rawl plug) is used to ensure screws driven into masonry walls provide a secure fixing. Without them, screws would not grip into masonry and would not provide adequate compressive force to ensure a secure, permanent fixing.
Installation usually involves ensuring first that the correct size plug is paired with the screw. As the screw must fit inside the plug, the hole to be drilled will be larger than it would be for the screw. The plug is inserted into the drilled hole and the screw is driven into the plug. As the screw penetrates the plug, it gradually forces the plug sides to expand outward, applying a compressive force against the masonry (which can be brick, block, concrete or plasterboard). The screw is tightened until it has fully penetrated into the plug, at which point it cannot be tightened any more.
Sometimes the screw turns indefinitely without tightening. This usually means the wrong size of plug has been used or the hole drilled is too big for the plug. One possible remedy is to take out the screw and take up the slack with matchsticks, filler, plaster pads or other material that will reduce the size of the hole, or to use a larger wall plug.
[edit] Composition
Typically, wall plugs are made of medium-duty, moulded plastic that can be used with a range of standard screws, from No 4 to No 14 sizes. They are usually tapered and profiled to increase their grip; they come in a range of profiles, colours and sizes.
Wall plugs are also supplied as extruded plastic – often straight tubes of 150mm-200mm lengths that must be cut to size according to requirements. But because they have straight sides, they must be cut shorter than the depth of the hole.
[edit] Threaded plugs
For screwing into less dense, friable walls, such as aerated concrete blocks, plugs are available with a thread on the outside; once screwed into the wall they form the socket for the screw and in all respects behave like ordinary wall plugs.
[edit] Nailable plugs
Nailable plugs come in various shapes and sizes and can be used with nails in masonry and plasterboard. They are useful when many fixing points must be made quickly. Both nail and plug are simply hammered-in as one fixing. Typical applications include fixing skirting boards, wall linings, battens and frames.
[edit] Related articles on Designing Buildings
Featured articles and news
Impact report from the Supply Chain Sustainability School
Free sustainability skills, training and support delivered to thousands of UK companies to help cut carbon.
The Building Safety Forum at the Installershow 2025
With speakers confirmed for 24 June as part of Building Safety Week.
The UK’s largest air pollution campaign.
Future Homes Standard, now includes solar, but what else?
Will the new standard, due to in the Autumn, go far enough in terms of performance ?
BSRIA Briefing: Cleaner Air, Better tomorrow
A look back at issues relating to inside and outside air quality, discussed during the BSRIA briefing in 2023.
Restoring Abbotsford's hothouse
Bringing the writer Walter Scott's garden to life.
Reflections on the spending review with CIAT.
Retired firefighter cycles world to raise Grenfell funds
Leaving on 14 June 2025 Stephen will raise money for youth and schools through the Grenfell Foundation.
Key points for construction at a glance with industry reactions.
Functionality, visibility and sustainability
The simpler approach to specification.
Architects, architecture, buildings, and inspiration in film
The close ties between makers and the movies, with our long list of suggested viewing.
SELECT three-point plan for action issued to MSPs
Call for Scottish regulation, green skills and recognition of electrotechnical industry as part of a manifesto for Scottish Parliamentary elections.
UCEM becomes the University of the Built Environment
Major milestone in its 106-year history, follows recent merger with London School of Architecture (LSE).
Professional practical experience for Architects in training
The long process to transform the nature of education and professional practical experience in the Architecture profession following recent reports.
A people-first approach to retrofit
Moving away from the destructive paradigm of fabric-first.
International Electrician Day, 10 June 2025
Celebrating the role of electrical engineers from André-Marie Amperè, today and for the future.
New guide for clients launched at Houses of Parliament
'There has never been a more important time for clients to step up and ...ask the right questions'
The impact of recycled slate tiles
Innovation across the decades.
EPC changes for existing buildings
Changes and their context as the new RdSAP methodology comes into use from 15 June.