If the roof ridge or a purlin crosses the opening, you'll have to relocate the opening and use an angled or splayed light shaft between the roof and the ceiling.
Its two-hinged parabolic laminated arches bear on tapered concrete columns through stainless-steel pins; they carry a secondary purlin structure which bears the double glass skin.
Modern attic rafters or traditional rafter and purlin construction will get you out of the forest of crossed members typical in a post 1960s house.
In the process, the various components acquired names according to their place in this system - king post, hammer beam, purlin , sill, and so forth - names that are still used today.
The first job he gave me, I was to use a drill mounted with a special bit to drive screws through the unpainted aluminium sheeting and the purlin below.
Roof sheeting rests on the purlins , and the whole is stabilized by diagonal ties under the deck.
The beams and purlins (the crosspieces) provide the support for the upper level and are made of construction-grade wood, complete with knots and other blemishes.
Horizontal tubular-steel purlins running over the arches in turn support vertically aligned tapered arms ending in stainless-steel fixings.
Extra outlet space can be got by raising every third row of roof sheeting by inserting battens over the purlins and nailing the sheets to these battens and purlins .
Roofs can be upgraded from thatch or asphalt-impregnated cardboard to clay tiles if the initial roof rafters and purlins are sized at the beginning to carry the weight of the heavier clay tiles.