Load bearing wall removal and RSJ installation
Structural RSJ works for knock-throughs, extensions and new openings, installed to an engineer's design and signed off by Building Control.
Knocking through a load bearing wall
Structural RSJ works are listed on our homepage alongside extensions and conversions, because most of the projects we build involve one. Joining a kitchen to a dining room, opening the back of the house into a new extension or forming a wide opening for bi-fold doors all mean taking out part of a wall that carries the floors or roof above. An RSJ, or steel beam, takes that load across the opening instead.
The engineer and Building Control
Removing a load bearing wall is structural work, so the beam, its bearings and the padstones under each end are sized by a structural engineer, who produces calculations for the opening. Those calculations go to Building Control, who inspect the work. We install the steel to that design; the engineer's design and the council sign-off are what make the opening safe and legal, and you will need the completion certificate when you sell.
How the work is done
The floor and ceiling above are propped with temporary supports so the wall can be cut out safely. Padstones or piers are built at each end to spread the load, the steel is lifted in and packed tight, and the props come out once everything is bearing. The beam is then boxed in with fire-resistant board and plastered, and any brickwork around the opening is made good.
Smaller openings, such as a new door or window, may only need a lintel, and old lintels over doors and windows sometimes need replacing when the wall above starts to crack. The same propping and bearing rules apply.
Living in the house during the work
Wall removal is dusty and noisy for a short time, then much quieter. Rooms either side are cleared and floors protected, dust sheets go up, and the props stay in place until the steel is bearing. Electrics, pipes and radiators in the wall are moved by the relevant trades beforehand. Once the beam is boxed in and plastered, the room is ready for decoration and flooring, and the Building Control completion certificate is filed with your house paperwork.
Steel beams in extensions
In an extension, steel often carries the house wall above a wide opening into the new room, or supports the roof over a large span of glazing. Those beams are planned with the extension drawings so foundations and padstones are in the right place before the shell goes up.
Questions people ask
- Can I remove a load bearing wall?
- Yes, with a structural engineer's design and Building Control approval. The wall is propped, a beam is installed on proper bearings, and the work is inspected.
- Can I remove a load bearing wall myself?
- It is not a DIY job. The loads involved are large, the work needs engineered calculations and Building Control inspection, and mistakes can be dangerous.
- What size steel beam do I need?
- That is decided by a structural engineer, based on the span, the loads above and how the beam bears at each end.
- Can a steel beam sit on brickwork?
- Usually on a padstone or a pier built into the brickwork, which spreads the load. The engineer specifies what each end needs.
- What affects the cost of removing a load bearing wall?
- The span, the beam size, how much propping is needed, the bearings at each end, making good and the engineer's and Building Control fees. We give a free estimate after a site visit.
Related: extensions · kitchen extensions · foundations and groundworks · loft conversions.