Standard specification and details
Page 14 – Top course, ridges, hips and gas flues
Standard Specification and Details - Top Course, Ridges and Hips
Top course and under top course slates must be of such length as to ensure that a correct lap is maintained. Under top course slates should be cut to size with the uppermost corners removed. The top course should be nailed and bedded at the head in mortar, thus causing the tail of the slate to fit closely on the course immediately below. If required, a slightly thicker batten can be used for the uppermost batten.
Ridge and Hip Tiles
Ridge and hip tiles must be bedded and jointed in mortar without separate pointing. Mechanical fixings must also be installed for every ridge or hip tile. Dryfix systems are also available and have mechanical fixings by nature. Where ridges meet, slate slips should be inserted under the junction and a solid mass of bedding squeezed up to fill the joint which is then struck off and smoothed with a trowel. The lower edges must be set in mortar to form a back bed which is not visible. A hip iron is fixed at the lower end of the length of hip.
A batten should be laid along each side of the hip tree. The slates are close cut and mitred down the line of the hip and laid with a light gauge metal soaker of sufficient size to lap and bond in with the slates of each course and to be nailed at the top edge. Wide slates are required for cutting so that sufficient width is povided at the head of the slates. The mitred hip cut should be formed in the reverse way to normal dressing (i.e.e the cut should be made with the slate face uppermost), thus giving a straight edge to the hip cut on the slate face. In exposed conditions and for roof pitches below 30° mitred hips are not recommended.
A batten should be laid along each side of the hip tree. The slates should be cut close to the hip and bedded in mortar ensuring that the lower edge of the slates fit closely on the course immediately below. All hip tiles must also be mechanically fixed.