On 27/05/2021 10:37, nightjar wrote:
On 26/05/2021 16:11, Tim+ wrote:
https://www.bbc.co.uk/news/uk-england-dorset-57253967
Would it be normal for the rafters to be tied into the brickwork to
resist
the gable potentially being €śblown out€ť?
Tim
It wouldn't be the first wall where the architect had failed to allow
for a strong wind creating a low pressure zone on one side.
Not helped by the design. That gable wall has a parapet and the roof
tiles form a 90 degree joint which has to be weatherproofed with lead.
London building regs used to make this mandatory to minimize the
spread of fire along a terrace of houses, but it means the roof
tiles do not overlap the gable (requiring a barge board arrangement
to finish it). This extension of the roof over the gable wall provides
a lateral locating function because the 'ladder' that is nailed,fixed
to the truss(es) immediately inboard of the cavity wall is built into
the cavity wall as well, locking the two together more securely.
That design should have had 1 metre long galvanised ties shaped
like hockey sticks buuilt into the cavity and screwed to the
underside of the trusses. This is potentially a windy part of
the country. Wind speed gusts of over 80mph were recorded on the IoW.