Finishing a roof: gutters, downpipes, balconies and parapets
Rainwater goods that follow the eave and come down on the wall, and a flat roof you can put a railing or a solid parapet round, side by side.
The details that make a roof read as a roof
A model can have the right pitch, the right overhang and the right tiles and still look like a cardboard box, because real roofs have things hanging off them. Two of those arrived recently.
Gutters and downpipes
Switch on Gutters & Downpipes in a roof's inspector and the roof grows rainwater goods that follow its own eave.
The work is in knowing where an eave *is*. On a gable the eave is two sides of four and the rakes get nothing; on a hip it is every side; on a flat roof the whole perimeter is eave. The trough follows the fascia line, and the downpipes hug the wall — which is inboard of the eave by the overhang — and run to the ground, not to the floor of the storey they started on. A second-floor downpipe that stops in mid-air is worse than none.
Set the gutter radius, how far it drops below the roof edge, the pipe size and where the downpipes go.
A balcony round a flat roof
A flat roof is the one roof you can stand on, so it is the one that can be given an edge. Switch on Balcony in a flat roof's inspector and pick from every balustrade style the balcony tool already draws — round rods, square balusters, glass panels, horizontal bars, cable — plus a new one: a solid wall.
A parapet is not a railing with a different infill. It has no uprights, no handrail and nothing between them; it is a mitred wall standing on the deck, held between 450 and 900 mm, because below that it is a kerb and above it a storey.
Which sides, and how far in
You do not have to take the whole way round. Each side is listed by the way it faces — "North · 8.0 m" — and you tick the ones you want. Sides next to each other are built as one run, so the rail turns the corner in one piece instead of stopping dead at it; tick them all and it is a closed ring that mitres the whole way round.
The inset slider runs from 0 to a metre and is measured from the roof's edge, which is the line you would stand at. An inset wider than the roof gives you no balcony rather than an offset outline tied in a knot in the middle of the deck.
Both, together
Rainwater goods and a parapet are not alternatives — a flat roof usually has both, the gutter behind the parapet. Switch on both and that is what you get, and the generated houses do exactly this: a flat roof there is never left as a bare slab.