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Ridges and Hips
What to look for:
- Missing tiles/sections of lead
- Missing mortar
- Distorted lead
Most shapes of clay ridge and hip tiles are easily obtainable. Make sure to use the same shape (V-shaped, half-round, or bonnet tiles) and colour. Replicas of ornamental (‘crested’) ridge tiles are readily available, and even cast iron cresting can be obtained easily.
Clay ridge tiles are usually fixed using a mortar bedding. Mortar in these exposed locations can often fail and this should be replaced with a suitable, durable mix (which should be lime-based for older buildings). Cement mortar will make it harder to repair a tiled ridge in the future, and can have an adverse effect on the softer tiles due to its hardness.
Lead roll ridges and hips should be retained or replaced to traditional details. Guidance is available from the Lead Sheet Association (see metal roofs and flashings below). Generally for historic buildings it is advised that lead of code 5 to 8 should be used for replacement depending on roof pitch and length of roll (codes of lead are based on thickness/weight of the lead sheet), but the thickness should be based on the original lead used and care should be taken on smaller ridges (such as those to dormer roofs) where thicker codes can lead to the detailing appearing clumsy. Ornamental lead detailing, such as scalloped edges should be retained and replicated. Modern detailing often specifies that the apron of the ridge flashing (the part that covers the roofing material) is longer than traditional, especially in areas prone to wind uplift. In general this should not pose a problem and the extra length would be essentially unnoticeable and worthwhile for a more weatherproof roof, however care should again be taken on smaller roofs, especially those with hips, where the lead can appear over-large and obscure more of the roofing material than is desirable.