When a dormer with a tile roof is covered with zinc, first the valley gutters are placed along the side bolsters of the dormer. These gutters will be connected to the existing standard gutter. The gutters are placed at the roof and to the side of the dormer by means of clips. The side panels are manufactured and bent backwards at the bottom and forwards at the top.
The sidewalls are attached with clips. The lower clips are already placed, because the valley gutter is attached with them. Then clips at the top are placed as high as possible, just under the roof overhang. The entire top can be covered by a strip of lead.
The clips should allow the cladding on the sides of the dormers to expand and contract freely. Otherwise the tension will damage the zinc. For the same reason it is better that the sides are covered not with one piece of sheet but with a system, for example standing seam, for a good application instead of soldering.
A flat roof covering is made by sheets, cut and folded to the correct measurements and soldered together the right way. The rear side of the covering is hooked over its full length for 20 mm. The fold is then covered with a lead flashing. The tiles should adequately cover this verge to protect it against rain and snow. The sill of the dormer will be sealed waterproof to keep the gutter leakage free, especially in the corners.
Joints and connections should always have sufficient space to guarantee the thermal movement of the zinc. Especially with this kind of application it is advisable to fit the coverings prior to soldering, clipping or seaming to prevent problems due to the thermal effects. Only then it is possible to perform correctly with waterproof details.