Open up a wall properly,and the room feels biggerwithout the ceiling ever knowing.

Working out what a wall is actually carrying means looking above it, not just at it: the direction floor joists run, whether a wall lines up with something on the floor above, and how the roof structure is framed all matter. In older North Devon properties, walls have sometimes been altered before, which can mean loads are already being carried in ways the original design never intended.

Where there is any doubt, we get the structural engineer involved early rather than after demolition has started. It is far cheaper to find out a wall is load-bearing on paper than to discover it once a ceiling has started to move.

Steel beams (RSJs and universal beams) are the most common solution for wide openings and heavier loads, sized by the engineer to the exact span and the load they carry from above. Timber beams or flitch beams, timber sandwiching a steel plate, suit smaller spans and situations where a lighter, more easily handled beam is preferable.

The beam is only half the calculation. End bearings, padstones and, where needed, additional strengthening to the wall below are specified alongside it, because a correctly sized beam resting on an inadequate bearing will still fail at the wall.

Before any wall comes out, the structure above is propped using acrow props and needling or a temporary support system matched to the load and the opening size. The sequence: prop, cut, remove, install beam, transfer load, remove props, is followed in order, with the new beam proven to be carrying the load before temporary support is taken away.

On larger openings or where two storeys of loading are involved, propping extends further than the immediate room, sometimes into the floor above, to make sure nothing is left unsupported during the work.

Forming a new opening in an external or internal load-bearing wall follows the same principles as removing a wall entirely: engineer's design, correct lintel or beam, adequate bearings, and propping during the work. Wider openings for bi-fold or sliding doors often need a heavier lintel than a standard window opening and careful attention to how the load either side of the opening is redistributed.

Where an opening is being formed in an external wall, weatherproofing detail, cavity trays, DPC continuity and insulation around the new opening, is built in from the start so the finished result performs as well thermally as the wall it replaced.

Removing a chimney breast, whether at ground floor or throughout a house, needs the same structural rigour: an engineer's assessment of what the stack above is doing, a specified beam or steelwork to carry any remaining chimney, and proper support while the work is carried out. Get this wrong and the result is a leaning stack or a cracked party wall.

Floor alterations: removing a section of floor for a stair opening, or strengthening a floor to take a heavier load such as a bathroom suite: follow the same principle of engineer's calculation first, construction second.

Structural alterations are notifiable building work, so building control is told before the job starts and inspects the completed structural work before it is covered by plaster or boarding. This is the independent check that confirms the beam, bearings and supporting structure meet the engineer's design and current regulations.

Once signed off, making good is where the job either looks professional or looks patched. Our own brickwork, blockwork, plastering and carpentry teams finish the opening: squaring reveals, making good ceilings and walls, and fitting any new door or window furniture, so the alteration reads as part of the house rather than an obvious repair.