Steel Frames for Home & Commercial Extensions
The structural steel frame for a single or double-storey extension, sized by your engineer and made and fitted by us. We detail, fabricate and install to your engineer's design, to BS EN 1090 Execution Class 2 and UKCA marked.
The frame an extension is built around.
Most home and commercial extensions need a steel frame somewhere: a beam to carry the floor above the new opening into the house, posts and beams to hold up a first-floor extension, or a goal-post frame across a wide rear opening. We make the structural steel for single and double-storey extensions to your engineer's design, from the beam over the knock-through to the whole superstructure of a two-storey build. Everything is fabricated in our own workshop to BS EN 1090 Execution Class 2 and fitted by our own team, tied into the existing building, so the steel that holds your extension up is made and installed by one firm and signed off with the right paperwork.
The beams, posts and connections of the extension frame.
Structural steel for single and double-storey extensions, fabricated to your engineer's design and fitted by our own team.
Working to your engineer's design
Your structural engineer sizes the frame from the design your architect has drawn. If you do not have an engineer yet, we can point you in the right direction.
The extension frame
We make the beams, posts and any goal-post frames for the extension, from the single beam over a rear opening to the full superstructure of a two-storey build.
Tying into the existing building
New steel has to connect to the house that is already there, so we detail and fabricate the connections that tie the frame into the existing structure.
Fitting the frame
Our own team sets the steel, on padstones, baseplates or into the existing walls, and bolts the frame together square and ready to build off.
Paperwork for building control
You get the fabrication drawings, weld records and declaration of performance, so the frame can be inspected and signed off.
The frame your extension is built around.
An extension leans on its steel: the beams over the openings, the posts, and the connections that tie it into the existing house. We fabricate the frame to your engineer's design under BS EN 1090 Execution Class 2 and fit it with our own team, coordinating with your builder for the groundworks, brickwork and roof, and hand over the paperwork for building control.
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Project & sample images.
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Why the frame is worth one firm from drawing to site.
The steel ties into the existing house and carries the new build, so it is made and fitted as one.
About UIS-
01
Made to your engineer's calculations
The whole frame is fabricated to the sizes and connections your structural engineer specifies, so the extension is supported as designed.
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02
Tied into the existing structure
We detail and make the connections that join new steel to the existing building, which is where extension steel most often has to be got right.
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03
BS EN 1090 Execution Class 2, UKCA marked
Fabricated to the execution class domestic and commercial structural steel is specified against, with the declaration of performance supplied.
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04
Fitted by our own team
One team makes the frame and installs it, and coordinates with your builder, so the steel goes in on programme and as drawn.
"I've worked with UIS for several years on some high profile and very complex projects. Their attitude and work ethic are second to none - providing high quality services and products which are delivered safely and on time every time. Overall they are a pleasure to do business with and wouldn't hesitate recommending UIS for any steelwork or metalwork packages."
Questions clients ask us.
An architect or designer draws the extension, and a structural engineer sizes the steel. Building control will want the engineer's calculations. If you have the drawings but no engineer, we can point you in the right direction, then fabricate and fit to their design.
We do the structural steel frame. The foundations, brickwork, roof and finishes are your builder's work, and we fit the steel into their programme, at the stage the frame is needed.
Yes. Connecting new steel to the existing structure is a normal part of an extension, and we detail and fabricate the connections to suit what is already there, often after a survey.
Yes. We fabricate and fit the frames for single and double-storey extensions, domestic and commercial, to your engineer's design.
We are based in South Yorkshire and fabricate and install across the UK with our own teams.
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