the permanent roof
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Permadeck with  soft single ply systems

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Slates or tiles to match

Various ways to drain

Can be frameless

Modern 'Mansard' - a flat roof on top of a slated or tiled pitch
Recessed or ‘sunken’ Mansard - the flat roof that looks like a pitched roof

A warm deck maximises the useable internal volume:

Really only practical because Permadeck can encapsulate the whole roof seamlessly.  Can be a balcony surface with full or half height upstands topped with a railing.  If used for a dormer, the falls can be taken back to the pitched roof where the water runs off down the side valleys.  Downpipes can go through soffits or angled through to the gutter or a hopper head on the wall.

Adds character to a flat roof

The possibilities with Permadeck are endless.  

Whatever the shape you have, Permadeck will encapsulate it - permanently!

Conventionally the decking stops where it meets the sarking but this causes lots of problems when you come to waterproof the roof AND it can look awful. Below you will see the decking projected over the sarking 150 - 200mm with a fillet or rail fastened below.  This fillet then carries the lead or Ubiflex that dresses over the slates or tiles without having any lead lying on top of the roof.  The Permadeck edge trim then covers the lead forming a weathertight seal and an attractive border to the top of the slates or tiles just like a ridge flashing does at the top of a normal pitched roof.  All sizes are a guide only and should be checked on site.
A recessed or ‘sunken’ mansard uses a similar detail and is a great way to transform an existing flat roof.

This is what it looks like in practice; this recessed mansard is also a balcony, hence the posts. NB This roof had additional trims on the inside top edge to add to the appearance.

Another example can be seen here: carport

Great for a dormer or as a balcony

on an extension.

In the beautiful Tay valley at Aberfeldy, this was a refurb of a standing-seam lead mansard roof that had corroded. The timbers below the standing seams were extensively rotten. We could have simulated the standing seams but since the roof is out of sight this wasn’t necessary.

Look carefully and you’ll see the old ‘lead steps’, ridge beam, and round rooflights; all very easily moulded into the Permadeck system.

The Art of Permadeck:

With a slope back and to the sides this sunken mansard was so simple to build yet gave a stunning appearance.  The eaves on this roof are extra deep to keep rain off the windows and the main roof has an older Permadeck ‘walkway’ for easy access along the length of the building.

Clever or what?

Permadeck on 18mm ply on min 1:80 firring

Hip truss

Lead apron

Tiles on battens on sarking on trusses

150 - 200mm


Want to use this space?

Vaulted Mansard

Permadeck was ideal for the top of this rather exposed 19th century mansion.

This house had been extended in all directions, but the lead coloured Permadeck mansard keeps the building in sympathy with its surroundings.