Check out all you need to know about the four most common roofing components available.
More in Home Improvement
Tile manufacturers now produce tiles shaped specially to finish different roof details. Cloaked verge tiles lap over the edge of a gable to finish the roof line neatly, and eliminate the need for any mortar to finish the verge (image 1). Hip tile and hip iron, also known as bonnets, are placed along the hip of a roof. Ridge tiles can be used instead, with a hip iron at the eaves to support them (image 2). Valley tile is shaped tile used in valleys in place of a flashing system (image 3). Ridge tile is an arched tile used to cover a ridge. May also be used along a hip, depending on the roof design (image 4).
For a small repair, choose felt to match what is already on the roof. If you need to lay new felt, think about whether you need it to be breathable—for instance, because the roof space is insulated and/or ventilated in a particular way. Breathable felt, often colored, allows moisture inside the roof to escape, but prevents moisture that is outside from getting in (image 1). Bitumen-reinforced felt, normally black, is very effective waterproof barrier (image 2). Plastic felt is an alternative to bitumen-reinforced felt, both non-breathable. The sheets should overlap to the dotted line (image 3).
Metal straps and plates are used to hold lumber together in roof structures—especially in modern trusses. These types of joints and plates make installation much more straightforward, as there is no need to cut complex wooden joints. Since roof structures have so many joints, they can be a considerable timesaver. There are several designs of restraint straps made for various uses and roof types. This rafter fits across the end rafters next to a gable and attaches to the wall (image 1). A timber connector is used to connect trusses to a wall plate and has small holes for fasteners (image 2). A truss clip fastens to a joist and is used to connect trusses to a wall plate (image 3). A heavy-duty truss hanger is more robust and used for deeper joists (image 4).
The waterproofing materials used in valleys, abutments, around chimneys, or at any other joint between different parts of a roof, are known as flashing. Metal flashings such as tin and lead are the most traditional type, and are still widely used despite modern alternatives. Lead flashing, a traditional flashing material, is hardwearing, waterproof and malleable, so it can be easily molded into the desired profile (image 1). Self-adhesive flashing repair is applied over damaged flashing for a repair. Primer may be needed before application (image 2). Glass-reinforced polyester (GRP) is now commonly used as an alternative to lead flashing for valleys and abutments (image 3). A lead dresser is for shaping lead along abutments and over different shaped tile profiles. It has curved and flat faces to suit all roof shapes (image 4).
Poor ventilation in a roof is a major cause of mold. There are a number of different options for ventilating a roof. Ridge and tile vents can be joined with ducting to waste pipes or devices such as a bathroom exhaust fan, but they must not be used instead of a flue for extracting hot combustion gases unless this use is specified by the manufacturer. Tile vents have an integrated vent. They are often plastic, and need to be installed with an underlay seal (image 1). Ridge vents offer direct ventilation channels through the ridge. This may be as part of ridge-tile or in the form of channels that are installed along the lower edge of the tiles as they are laid in place (image 2). Fascia vent clips onto fascia. The channels in the lower section allow for airflow through fascia and into loft space (image 3).