Knocking through a wall: how a structural alteration actually runs

First question: is the wall carrying anything?

Not every internal wall is load-bearing, but you cannot tell reliably from tapping it. Joist direction, what sits above, whether the wall lines up with walls on the floor above, and whether it supports a roof purlin or a water tank all matter. In older South Devon houses, walls that look like partitions sometimes pick up floor loads after decades of alterations nobody recorded.

On the first site visit we lift a floorboard or look in the loft where we can, check the joist runs and note anything unusual. That tells us whether a structural engineer is needed before we can give you a firm written quote.

The engineer's role and what the calculations give you

If the wall is structural, an engineer calculates the size of the new beam, what it bears on at each end and whether the existing walls or foundations beneath those bearing points can take the concentrated load. The result is a set of calculations and usually a simple drawing.

Those documents are what building control checks the work against. They also stop guesswork on site: the beam size, padstone detail and fire protection are all specified before the job starts rather than decided on the day.

• Beam size and material (steel or engineered timber)
• Bearing length and padstone or pier details at each end
• Any new foundation pad needed under a point load
• Fire protection to the beam where regulations require it

Temporary support while the wall comes out

Before any masonry is removed, the structure above is propped. Typically that means adjustable steel props and needles passed through the wall just above the new beam position, spreading the load onto the floor below. The props stay until the beam is in, packed tight and the bearings have gone off.

This stage is where rushing causes cracks upstairs. We take the wall out in a controlled way, keep the dust contained as far as practical and check the ceilings above as we go.

Building control, inspection and covering up

Removing a load-bearing wall is building-regulations work whether or not planning permission is involved. The building control inspector will normally want to see the beam and its bearings before they are boxed in. We plan the programme around that visit so nothing is plastered over early.

Once signed off, the beam is fire-protected as specified, the openings are made good and the room is replastered. Floor levels often need attention where the old wall stood, because the two rooms were rarely finished at exactly the same height.

What changes the scope

Services running through the wall — cables, pipes, gas — need rerouting by the appropriate trades. Chimney breasts removed on the ground floor need the stack above supported properly, not left hanging on brackets without calculation. In semi-detached and terraced homes, work near a shared wall may bring the Party Wall Act into play.

We raise these points at quote stage so they are priced and planned rather than discovered halfway through.

• Electrics, plumbing or gas buried in the wall
• A chimney breast or stack above the opening
• Party wall notices on attached houses
• Uneven floor levels once the wall is gone

How we run it

Anthony runs structural alterations directly with our own team, alongside the carpentry and plastering that follow. You get one written scope covering propping, removal, beam installation, inspection and making good, rather than several trades each pricing their own slice.

Common questions