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How to build your dormer « Back

  • Step 1

    Upon receiving your dormer kit, unpack and check all components.

  • Step 2

    Assuming you have already positioned your double rafters to accept the dormer kit, locate your desired position and put a parallel line on your double rafters. Measure down from the ridge or up from the plate to achieve this. Then strike a line on all the rafters between the double rafters. Plumb this line down and cut off the rafters to this mark. Then cut the same rafters approximately 1200cm above these cuts to clear some space to work within.

    Slot your cill trimmer into position, resting on the double rafters at either end and fix the cut rafter feet onto the trimmer.

  • Step 3

    Slot your cheek sections into position located on top of your double rafter and inter locking into the cill trimmer. Fix down into double rafters with fixtures provided.

  • Step 4

    Slot your window lintol section into the housing within the cheeks and fix with fixings provided. Also locate and fix any cheek returns or gable ends at this stage.

  • Step 5

    plumb level the box section of your dormer and tack a temporary batten across to keep it level. Pull and level horizontal line across the top of the cheeks until it strikes the back of the double rafters. Then, at this position strike a horizontal line up the double rafters. These two lines are the locating position for the ceiling trimmer . The rafters within the dormer will need a plumb cut in line with the vertical line on the double rafters to align with the ceiling trimmer

  • Step 6

    Fix your ceiling trimmer into position and secure all necessary existing rafters and ceiling joist onto trimmer

  • Step 7

    You are now ready to install the roof sections of your dormer. Install a pair of common rafters and ridge board.

    Then place a straight edge across the back of these rafters to gain the position of your lay boards onto the existing roof. (Picture 15 down/2,3,4 across).

    If your dormer is of a hipped design position, fix hips at this stage. You are now ready to infill all rafters and ceiling joists, as numbered accordingly.

  • Step 8

    With your dormer structure now complete, you are now ready to fit all fascia, soffit, bardge boards and any decorative features supplied.