Roof

One of the big pains of converting the loft is keeping the whole lot reasonable watertight during the work. This involves lots of plastic sheets which waste loads of time fixing and unfixing every time you want access to the house to do some work. Hence once the dormer shell is up the race is on to get ready for the roof.

The first stage is the construction of the "warm deck" roof. This is simply 80mm thick sheets of cellotex laid directly over the firings on the roof joists with 3/4" shuttering ply placed on top. The whole lot then being screwed down firmly (with getting on for two hundred 5" screws!).

You can get pre made sheets with the insulation already bonded to "wood", but investigation revealed that the wood in question is usually something feeble like 6mm ply. It seemed this would allow too much movement of the roof surface (when walked on), which in turn could damage the roofing felt at the joints.

The next thing to do is prepare all the edges of the roof. This requires building "upstands" at the side and back of the slope of the roof (2" aris rail was recommended by the roofer for this).

Also before the felt can go on we need all the soffits and facias fitted. The final step is the easy one - sit back and watch the roofers do all the work!

Here is a shot of the facia and soffit on the roof. We used a "stepped" appearance to help break up the large vertical height of the roof line. The top section with the felt "drip" houses the ply and insulation layers. The bottom facia clad section covers the ends of the roof joists. It is stepped back a little such that the top section should drain directly into the gutter when fitted!

Looking over the top of the roof reveals a very neat and tidy job. The bulk of the (large) area of the roof is finished in a bright silver reflective coating which is painted over the three layers of hot bonded felt. This gives better protection and thermal performance than the traditional "mineral chipping's" finish often used on flat roofs. The mineral chipping finished felt is just used round the edges to create a more pleasing finish to the bits you can see from the ground.