Indy Total Construction

The tiles on each side of the roof apex are sealed by ridge tiles. These span both upper courses and are bedded on mortar.

Replacement is carried out by chiseling out the old mortar and levering the old tile off. Then a new one is fitted on a fresh bed of mortar. Slate roofs are treated in the same way although sometimes they may have lead sheet wrapped over the ridge bar instead.

Gable tiles

To avoid there being a toothed pattern to the gable edge of the roof, special wide tiles and slates are made which are one-and-a-half times the normal width, allowing a square edge to be produced.

Eaves tiles

To ensure that the overlapping pattern of the roof continues at the eaves, a course of shorter tiles or slates is nailed in place so that their ends are flush with the course immediately above, but their joints are staggered by a half tile width.

Valley and hip tiles

Where two roofs meet there must be some means of joining the courses of tiles to ensure a watertight seal. It is usual to form a gutter along the angle of the join to carry water away. Use zinc sheet, or valley tiles which are nailed to the roof members and often interlock with the adjoining courses.

Directions:

1 Measuring the projection of the gable-end tiles; bed the undercloak tiles face down in mortar and tuck the inner edges under the felt.

2 Setting the end tiles into mortar on the undercloak; use alternate full-width and widthand-a-half tiles to level edge.

3 Repointing the verge after the mortar has hardened; a pigment added to the mortar will make the pointing less obtrusive.

4 Checking the size of a cut tile adjoining the valley; this must allow the valley tile to be firmly bedded down beside it.

5 Working from the bottom of the valley upwards, aligning the bottoms of the valley tiles with the adjacent cut tiles.

6 Bedding the first hip tile into mortar; this must be shaped to prevent it overhanging and is supported by a hip-iron.

Slates are fixed to the roof in rows, or courses, each course overlapping the one below by at least half a slate length. In addition, the joins between slates in adjacent courses are staggered: in this way the joins are always covered by the slates above or below to ensure a water-tight construction.

Where the roof has a gable end, wider than normal slates are fitted to the ends of alternate courses to produce a square edge to the roof (these are known as “slate-and-a-half” slates). In addition, the edge slates at a gable end may be bedded on mortar laid on stacks of narrow slate strips known as creasing slates. These tilt the edges of the slates upwards so that rainwater runs down the roof to the gutters.

In addition to cutting them to size as described opposite, you will also have to make nail holes in them — no closer to the edge than lin. Use an old slate as a template for marking the holes.

Make the nail holes by drilling them or by driving a nail through with the slate supported on a block of wood. For safety and ease of working, do the cutting and drilling on the ground and carry the finished slates up to the roof. You will need 1 ‘Ain copper, zinc or aluminum roofing nails to hold the slates in place.

Remove the old slates from the roof using the slate ripper and starting with the upper courses of the area to be renewed. As you remove these upper slates, you will expose the heads of the nails holding the slates below. Cut these off with a pair of pincers.

Collect the slates and lower them to the ground with a bucket and rope, taking care with whole, undamaged ones, which you will be able to refit.

Having stripped off the old slates, inspect the battens below and if any are broken or rotten cut them out with a saw.

Begin fitting the new slates, starting at the lowest course and nailing them to the battens to recreate the overlapping pattern of the roof. Use two nails per slate and make sure it is fitted with the beveled lower edge uppermost to aid drainage.

Work your way up the roof, nailing the slates in place until the surrounding original slates make this impossible. Then fit the other slates with lead clips or toggle clips (see opposite) to complete the repair.

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.