The design of this roof was a low level kitchen extension warm roof. the extension was down the full side of the property and wrapped around the front elevation.

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Inlayed gullys were formed front and rear and a slight fall from the centre of the roof
created to take the rainwater to both gullys
 
The  timber construction was initially formed by the the joiners on site who also created
a fall from the centre of the roof to the front and rear sections using timber furrers. They
then installed 100mm Kingspan insulation onto the timber joists of the whole roof except
around the planned front and rear rainwater gullys, before the roof and gully was fully
decked in 18mm OSB3 interlocking boards.
 
We then set about installing preformed trims to the full internal and external perimeters,
raised edge trims were used to the outer perimeter to keep the water on the roof as the
inlayed gullys were designed to remove the excess rainwater internally. Wall fillet trims
were used to the internal perimeter and around the to skylight frames designed into the
roof and also around an existing hanging tile bay the new roof was built around
 
Once all the preformed trim work was completed we installed leadwelded outlet pipes to
the gullys - one per gully - and fixed in place, before bandaging all the joints and corners
of the trims using activated grp resin and fibre glass bandage roll, sanding these to a smooth
finish once the resin had hardened sufficiently
 
The main roof  was quite a big area (approx' 40sqmtr) made into various sections of differing sizes
and shapes due to the rooflights, bay and inlayed gullys. Given this, we always precut most if not
all of the matting pieces beforehand so we're constantly laying the system and not stopping to cut
pieces while we've got activated resin going off in the tubs. It was a very hot day on this occasion so
preparation was everything. The grp system and the activation process is all temperature related so
working this out so its activated correctly (more activation when cold less when hot) is critical to
you getting the job done without any problems, liquid setting too quickly or too slow is a problem that
everyone doing this system will have experienced at some point in their working life, if they say they
haven't, you've got my permission to call them a liar. Its part of the learning process to experience these
type problems, and from my own experience and talking to friends or other contractors who install grp
it can take up to 10 installs before you're accustomed to the problems that can be thrown at you laying
a fibre glass roof. We've got to the stage now, whether its bitterly cold or roasting hot, we can lay three
 5mtr sections of matting and the 1st section has gone off as we're finishing the 3rd section, and so on
 
Once we had everything cut to size we then worked in sections laying the matting, resin onto the boards
1st, matting rolled over the top then more resin onto the top side of the fibre glass matting, before pad
rolling the resins through so no dry matting was visible (this will look white to the eye and can easily be
remedied by applying a bit more resin to the matting and pad rolling again)
 
Once hardened, we applied a layer of activated topcoat to the full roof area and preformed trims. The
following day we gave the roof a good sanding to smooth out any little defects, fitted code 4, 6" lead
flashings to the walled section and pointed in place, before giving the full roof a 2nd coat of activated
liquid topcoat to complete the 3 layer grp system