Enlarging the Opening

Filed Under: DIY Outdoor, Do it yourself, Remodeling    by: ITC

Having set the new lintel in place and re-finished the brickwork of the inner leaf above it, you can cut out the brickwork at the sides of the opening and, if necessary, across the base. First, draw the outline of the new opening on both sides of the wall, making it about lin wider and deeper than the actual frame dimensions to give a fitting tolerance.

External walls comprise two layers of bricks; each layer should be treated separately, working in from each side of the wall.

If the wall is a solid one produce a square edge along the opening outline on the inner layer by cutting through bricks where necessary. Always remove complete bricks even if they project beyond the outline. This gives a toothed effect to the edge.

If the base outline runs through the center of a course of bricks, remove the course completely; you can make up the difference later.

Replace the outer layer at the sides of the opening by mortaring cut bricks into the toothed sections so that their cut ends are innermost.

Next, replace the area of wall above the window, laying the bricks on the lintel and copying the original brickwork bond for strength and appearance. In a solid wall, you can create a curved, self-supporting soldier arch by setting a wooden framework in the opening on which the bricks of the arch are laid. Then the surrounding courses are fitted round the arch and the mortar left to set for a couple of days before removal of the formwork.

The frame must sit squarely in the opening; if it is twisted, you may have problems in opening and closing the window and the glass will be under stress and may shatter at the slightest vibration.

In a solid wall you can set the frame: flush with the outer face with its sill overhanging the edge; in the center of the opening with narrow reveals on each side; or flush with the inner face with a sub-sill at the bottom to throw water clear of the wall.

When the frame is set forward in the opening, the sides and top of the reveal are plastered and a wooden or tiled window board set across the bottom. When set at the back, it is normal to trim around the inside of the frame with molding

The simplest method of securing the frame is with frame fixings, a hefty screw and long plastic wall plug, but you can also use conventional wallplugs and screws, wooden wedges or metal frame ties. With each type, wedge the frame in the opening with wood offcuts so that it is set squarely in place, while the fixings are marked and made.

With screws and plugs, clearance holes must first be drilled in the frame and the hole positions on the wall marked through these. The holes are drilled and plugged and the frame fitted.

Wooden wedges are tapped into slots cut in the mortar joints and the frame nailed to the wedges. Metal frame ties also fit into slots in the joints, being screwed to the frame and mortared in place.

In all cases, you must leave a’/sin gap between the top of the frame and the underside of the lintel to allow for any settlement of the structure.

Leave the packing pieces in place. and fill the gaps at the sides with mortar, leaving it about 1/sin below the level of the frame face. Fill this gap with caulk when the mortar has set. Use caulking to fill the gap between the lintel and frame also. If there is a gap below the frame, fill this with bricks and mortar, splitting the bricks lengthways if necessary.

Make a sub-sill from wood screwed or nailed in place, or a double layer of tiles set on a sloping bed of mortar.

Another way is to cast a concrete sill in situ, making up a wooden formwork “tray” nailed to the wall. The sill should overlap the edge of the bricks by no more than in and you can form a drip channel (to prevent rainwater trickling under the sill) along the bottom edge by pinning a length of waxed cord (sash window cord will do) in the bottom of_ the tray. The top of the lintel should slope downwards so angle the sides for this. Also provide reinforcement by setting steel rods in holes drilled in the brickwork.

Mix the concrete from 4 parts sand: 1 part cement and pour it into the form. Agitate the mix to compact it and remove air bubbles and draw it off level with the top of the form. Leave the concrete for at least 24 hours before removing the foiinwork.

The frame fixing is much simpler to use and is ideal for securing wooden members to masonry. It comprises a hefty screw and a long plastic wallplug.

To use, wedge the frame in its opening and drill holes for the fixings right through it and into the wall. Without removing the frame, tap the plug and screw combination through the frame and into the wall, finally tightening the screw for a secure fixing.

Frame fixings are supplied in various lengths to hold wood thicknesses up to 33/sin. Another development of this is the hammer fixing, which is used in the same way, but set by driving a ridged, countersunk pin into the expanding plug.

Fitting a New Lintel

Filed Under: DIY Outdoor, Do it yourself, Remodeling    by: ITC

With the wall above the window opening supported by stout wooden needles and adjustable jacks, and the old window frame taken out you can remove the old lintel and brickwork from above the opening.

Remove the bricks from the outer layer first. These may be laid in horizontal courses across the lintel or they may be set vertically. If the house is old, they may form a self-supporting segmental arch.

Cut through the mortar joints with a bricklayer’s chisel to remove the bricks, making a gradually tapering, stepped opening up to the level of the wooden needle above. This will prevent any brickwork from falling while working on the opening.

Removing the bricks from the outer leaf of the wall will expose the face of the load bearing lintel set in the inner leaf. You should remove this next.

From inside the house, hack off the plaster above the window opening to expose the inner face of the lintel and the brickwork above it. Again, cut out the bricks to foam a stepped opening up to the level of the needle. Then cut into the mortar joints at each end of the lintel, working along the top, ends and underneath. Use a stout bar to lever the ends of the lintel upwards to finally release them. Then get some help to lift the lintel from its bearings in the wall.

the thickness of the wall. It may lodge and form a bridge for moisture to cross from the outer skin to the inner and cause damp patches on the inner wall.

Measure up the new lintel and draw its outline on the inside of the wall centered over the new window position. Remember, the new lintel should be at least 6in wider at each side of the window opening to provide decent-sized bearings. Also, allow an extra lin at each end and on the depth to provide enough space to manoeuvre the lintel into position.

Cut straight down through the plaster along the outline with the bricklayer’s chisel to provide a cutting guide and then hack off the plaster within the outline.

Go on to remove the bricks exposed by the removal of the plaster, again cutting through the mortar joints in an effort to keep as many bricks in one piece as possible. Clean up the bearing openings and make sure their surfaces are flat and level.

Whether you are using a steel or concrete lintel, you will need some help to lift it into place.

Trowel a layer of mortar onto each bearing and lift the lintel into place, setting it centrally over the opening. Check that the lintel is flush with the inner face and outer layer of the wall.

Hold a level against the underside of the lintel and check that it is horizontal. If necessary, correct this by packing pieces of tile or slate beneath the ends. When level, fill the gaps round the ends of the lintel with more mortar and brick offcuts, pointing the joints neatly flush with the surrounding brickwork.

Cutting an External Doorway

Filed Under: Do it yourself, Remodeling    by: ITC

The positioning and installation of external doors is subject to the requirements of your local building code, so make the necessary applications to your local building department first.

Temporary support for the wall must be provided by Sin sq needles on top of adjustable metal props. To fit the needles, remove a whole brick from the outer layer and drill through the inner layer at the corners of the opening. Use the holes as a guide for cutting out the masonry from the inner layer. Insert the needles and tighten the props.

Draw the outline of the lintel on the inside wall and cut out the plaster and masonry from within. Drill the corners of the outer layer and remove the masonry. Fit the lintel on mortar bearings packed out with tiles or slates to set it level. Fill all round the inner portion of the lintel with mortar and rebuild any brickwork above it. Similarly rebuild the outer brickwork in the existing bond or stand the bricks on end to form a “sodier” arch.

When the mortar has set, remove the needles and brick up the holes. Then cut out the opening for the door frame — to fit the size of the frame.

Remove the bricks down to floor level, cutting through the protrud-bricks of the inner layer, on solid walls but removing whole bricks from the outer layer to give a toothed appearance. Square up the toothed outer layer by fitting cut bricks in place so that their “finished” ends are outermost.

Toe-nail the frame together before inserting it in the opening. Tack a length of flashing material to the underside of the sill, covering the nail heads with a bituminous sealant.

Fix the frame in the opening with screws and wallplugs, packing the sides to make them vertical. Fill gaps on the inside with mortar; apply caulking around the frame on the outside to keep out water.

The door sill should overhang the brickwork slightly and is best fitted with a metal weather bar, which is set in caulk. Once the frame is in place, hang the door and finish.

Making a New Doorway

Filed Under: Do it yourself, Remodeling    by: ITC

As with all jobs of this type, making a new doorway requires careful planning. You should also check the requirements of your local building code.

A lintel must be chosen to match the type of wall being cut into and you must select a position for the door that, if possible, will not interfere with existing cable and pipe runs and which should be at least 18in from any corner.

It is possible to buy doors and ready-made frames in a range of standard sizes, and unless you are making the frame, it is best to buy the door and frame first, making the opening to fit it. Make sure its height leaves enough of the wall above the opening for fitting the lintel and the temporary wood supports.

With a masonry wall, you must provide temporary support for the wall above the opening and the load it carries while you cut out a slot for the lintel. If the wall supports the joists of the ceiling above, you must also make sure you support the ceiling on both sides of the wall as well.

Support the wall with 6ft lengths of 2 x 4in wood called “needles” — on top of adjustable metal props, which work like an automobile jack (you can rent these), spaced at 3ft intervals. With a normal sized doorway, you would need only one set centrally above the opening.

To support the ceiling, lengths of 4 x 12in wood are used across the tops of more props. None of the props should be more than 2ft from the wall, and if they are to stand on a wood floor, the feet should be placed on another length of 2 x 4in wood to spread the load.

Before marking out the doorway on the wall, use a bricklayer’s chisel and hammer to remove patches of plaster roughly where the edges and top of the opening will be. This will allow you to adjust fairly accurately the position of the opening to coincide with the mortar joints, in order to reduce the number of bricks you have to cut through.

Measure up the door frame, adding 2in to its width and lin to its height to allow for positioning. Using these dimensions, draw an outline of the opening on the wall. Then measure up the lintel — which should be at least l ft wider than the opening — and add a further 2in to its width for fitting. Draw the outline of the lintel on the wall above the door opening.

Finally, draw the outline of the wood needle centrally above the needle outline. Repeat the outlines on the other side of the wall.

Cut the hole for the needle with a hammer and bricklayer’s chisel. Slide the needle through so it protrudes equally on both sides of the wall and fit the props beneath it, tightening them to take the load. Both props must be adjusted simultaneously to ensure even support. Then fit the ceiling supports.

Bridging Openings

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

The way you tackle the job of making an opening in a wall or removing the wall completely in your house, depends on the type of wall it is and its construction.

A load-bearing wall contributes to the strength of the house by supporting some of its structure: a floor/ceiling, an upstairs wall or part of the roof.

A non-load-bearing wall is simply a dividing partition and its complete removal will have no effect on the rest of the house.

Inspect the floor space above it for signs that it supports the joists, or an upstairs wall. Look in the attic, too, to see if any of the roof framework rests on the wall in question.

All external walls are load-bearing and in general any wall at right-angles to the joists will be load- bearing too. Walls that run parallel to the joists are probably non-load-bearing.

Walls may be of brick, concrete blocks or be wood framed. All three types of construction are used for both load-bearing and non-load-bearing walls.

When you make an opening in a wall, no matter how narrow or wide, you must insert a supporting beam or lintel across the opening to take the load of the structure above, even if it is a non-load-bearing wall. The problem is that even by removing a narrow row of bricks or blocks to make room for the be will put the structure at risk.

For a narrow opening like a door, the bond in pattern of the bricks or blocks will tend to make the wall above the opening self-supporting (or self-corbelling) and only a small triangular section of masonry will be at risk. This can be removed, the lintel fitted and the masonry replaced.

With a very wide opening, the self supporting tendency will disappear and a wide area of the wall will be liable to collapse. To prevent this happening. you must support the wall (and sometimes the ceiling on either side) temporarily with heavy wood and adjustable props.

Openings in walls may be spanned by lengths of concrete, steel or wood. Those for fitting over small openings like doors and windows are called lintels; those for spanning wider gaps are called beams. The following are common: Steel Joist — a heavy I or L-shaped girder for spanning very wide gaps in load-bearing walls; Reinforced Concrete Lintel — for internal or solid brick external walls in spans of up to 10ft.

Heavy to lift and often cast on the job site, is the Pre-stressed Concrete Lintel — lighter than reinforced concrete lintels but not suitable for load- bearing walls, except in upper floors. For spans of up to loft, the wood lintel is used in wood framed walls.