Indy Total Construction

Wearing protective clothing, (especially the goggles), carefully cut away the plaster from within the lintel outline to expose the masonry below. Remove the bricks or blocks by cutting through their mortar joints and lifting them out. If any above the slot should drop, remove these and keep them for replacement later. Retain any whole bricks from the slot for possible reuse.

Lift the lintel into place, bedding it on mortar (3 parts soft sand: 1 part masonry cement) laid on the “bearings” at each end of the slot. It is best to get the help of an assistant with lifting the lintel, especially when lifting weights above the head. Make sure the lintel is level and, if necessary, pack it out below the ends with tiles or slates.

Finally, fill any spaces around the lintel with more mortar and replace any bricks or blocks that may have dropped out at the slot-cutting stage. If the wall is constructed of blocks, bring the lintel up to the height of the adjacent blocks by laying a course of bricks on top, and mortering them in place.

Leave the mortar to set for at least 24 hours, and preferably 48. Then remove the needle and wood supports. Fill the needle holes with brick offcuts and mortar. Lever off the baseboard and place it to one side for cutting down later.

Remove the plaster inside the outline of the opening to expose all the masonry below. Using a light sledge hammer and bolster chisel, cut this out by chiseling through the mortar joints, carefully working down the wall one course at a time. Because of the bonding pattern used, you will find that on alternate courses you will have to cut through bricks at the sides of the opening. Do this as you come to them. driving the chisel into their faces and levering them out from below to leave a straight edge to the opening. Remove all the bricks from the opening.

Trim off the masonry flush with a solid floor, or jus: below a wooden one. In the latter case, join the tv,-: floors by screwing battens to the joists then fit a piece of plywood or short pieces of floor-board on top neaten and close the gap.

The frame can be held in place with either galvanized metal ties mortared to the wall, or by screws and wall plugs. If ties are to be used, you need three per side. Cut recesses in the sides of the opening for the ties. If you intend screwing the frame to the wall, drill screw clearance holes in it and offer it up so these can be marked on the wall. Drill and plug the holes.

Set the frame in place, packing out the sides as necessary with wood offcuts to set them vertical. Then either fill the tie recesses with mortar and brick offcuts or insert the screws.

Fill in the gaps round the frame with more mortar and offcuts and trowel a thin layer of mortar over any exposed masonry at the sides and top before refinishing the plaster.

Finally, nail lengths of molding around the frame, mitering the corners, and trim and refit the base boards to the base of the wall.

Although a wood-framed partition is easy to build, it does not provide the most effective sound insulation and it will need extra strengthening if it is to carry shelves or cabinets. In situations such as this, a partition built from lightweight concrete blocks is much more suitable. However, you cannot build such a partition on an upper floor, since even a reinforced concrete floor is unlikely to be strong enough to carry the load of a concrete block partition. A concrete first floor makes an ideal foundation and even a suspended wood first floor will do if a full-width wood sole plate is put down first, but check with your local Code.

Before starting work, the floor, walls and ceiling should be stripped of all coverings and any coving and base cut away with a chisel to clear the blocks. The easiest way to mark the position of the partition is

with a chalked plumbline, snapping it against the floor to leave two parallel chalk lines the width of the blocks. Continue these lines up the walls and across the ceiling making sure they are vertical.

For strength, it is best to tie the partition to adjacent walls by cutting recesses in them to accept the end blocks of alternate courses or similarly by using galvanized metal ties screwed to the walls and buried in the blockwork mortar joints. Nailing a guide batten to the wall against one of the chalk lines is also a good idea to help with the alignment.

Trowel a 6in wide layer of mortar (1 part masonry cement: 6 parts soft sand) across the floor to span the chalk lines on it, leveling it out to about 1/2 an inch thick. Then scribe a guide line through the mortar in line with the chalk marks on the end walls, using the point of your trowel and a long straight-edged plank.

There are many different types of concrete block to choose from, but the best types for building an internal partition are known as aerated blocks (A).

These are light in weight, so they are easy to handle — an important quality since they are twice the size of a normal brick. This fact also means that you can build a full-height partition relatively quickly. You can drill them, knock nails into them or, using a general-purpose saw, cut channels in them (B) to conceal electric cables and pipe work. Sound will not pass through them as easily as it would a woodframed partition, nor will heat.

Aerated blocks should be laid in the same manner as bricks in a “stretcher” bond pattern with mortar joints. Their normal size is 17 x 81/2 x 4in. For finishing, you can either plaster them directly or nail on battens and fix a gypsum board cladding to the battens.