Standard Specification and Details - Abutments, Firestop Walls and Vertical Cladding

Abutments

The slates must be dressed close to the wall and a soaker inserted in each course. The length of the soaker should be 15mm longer than the combined gauge and lap of the slate, thus allowing the head of the metal to be nailed to the batten. The leadworker should then cover the exposed soaker with a lead flashing. Secret gutters are not recommended.

Firestop Walls

The wall structure should be cut approximately 25mm lower thatn the top edge of the adjacent rafters. A layer of 50mm fibreglass is compressed on top of the wall; a sheet of fireproof insulating board the same thickness as the slate batten is then fixed on top, being secured to the adjacent rafters. Slating battens are butted against the insulating board and the roof slating carried across and nailed direct to the insulating board.

Vertical Slating and Cladding

Slating to steep or vertical pitches should be carried out in exactly the same manner as roof slating, but using smaller sized slates. When vertical slating abuts main roof slating, the vertical slates should be cut as closely as possible to the main roof and made weatherproof by inserting soakers under each course of main roof slating. Where a change of pitch occurs between a main slated roof section and a mansard or vertical slated section, an apron flashing should be used, fixed under the main roof slating and dressed down over the heads of the slates below. The top course of the vertical or mansard slating should fit closely on the course immediately below, and a sound bed is formed to receive the flashing. Vertical angles are formed in the same was as the mitred hip.