Once you are satisfied that the opening will be an improvement to your home’s layout, consider the practical problems. First, determine whether the wall is loadbearing or a non-loadbearing partition: bear in mind that a loadbearing wall will need a beam spanning the opening with at least 150mm (6in) bearings at each end. Mark out the proposed opening on the wall with chalk to help you visualize its size and proportion.

The most suitable beam is usually a -oiled-steel joist (RSJ), although this :ype of beam will require preparation before it can be plastered over. Reinforced and prestressed concrete lintels can be used for openings up to about 3m (10ft), but, over a wide span, their weight makes them difficult to handle; prestressed types are lighter, but better for single door or hatch openings rather than wide spans. Pressed-steel box lintels — available in lengths up to 5.4m (about 18ft) — are :ighter and can be plastered directly.

The height of the opening is to some extent determined by the height of the ceiling and the depth of the beam. The latter is determined by the width of the opening the beam has to span, and the load it must carry. Consult an architect or structural engineer who, for a fee, can calculate this for you. The beam can be positioned directly under the ceiling joists of a low ceiling.

Before any work is started on a loadbearing wall you must seek approval from your local authority’s Building Control Officer. He will require a drawing showing the proposed opening, its overall height and width and how the structure above the opening is to be supported. This need not be drawn up by a professional, but it should be clear. Approval is unlikely to be withheld provided the work complies with the Building Regulations. The BCO must be satisfied that the removal of the wall will not weaken the structure of the house, or any buildings attached to it, and that it will not encourage the spread of fire. Where a party wall is involved, it will be necessary to get written approval (a party award) from your neighbour. The BCO will advise you.

The supports are usually brick piers, which are in effect columns attached to the side walls and formed from the remainder of the old wall. Concrete padstones are required on which to sit the beam. The BCO may want the piers increased in thickness to give sufficient supportto the beam and the side walls.

Ideally, it would be better if no piers were used as they interrupt the line of the side walls running through. It might be possible to run the ends of the beam into the walls, eliminating the need for piers, but this is subject to Building Regulations approval. It requires a horizontal concrete beam called a spreader to be set in the wall and distribute the load across more of the wall.