homebuilding.co.uk 83S
elf-buildersspenda great
dealoftimestudyingbuilding
systemsandpondering
whethertooptforconventional
on-siteconstructionorswitch to
a factory-built,off-sitesystem.
Habitually,theybeginandend by
lookingat wallingsystems.The
roofis addedon,almostas an
afterthought.
Butthereareverysimilar issues
toconsiderwithroofingand it is
worthmakingyourselffamiliar
withtheoptions.The roof structure
Although roofing can be steel-
based or even pre-stressed
concrete, the bulk of roofing
structures are timber-based, to
which insulation is added and a
variety of membranes to counter
both external weathering and
condensation issues stemming
from inside the structure. Today’s
roof cover, the material you
actually see from the outside, is
but the topmost layer of a thick
bed of materials sitting beneath it.
Until the 1960s, all house
roofs tended to be built using an
age-old routine involving a high
level of carpentry skills and a lot
of load-bearing timbers. Think
rafters, ridgeboards, purlins and
wallplates, plus various bracing
pieces to tie them all together.
A 1950s roof wouldn’t have
looked out of place on a Tudor
farmhouse or, for that matter, a
Roman villa.Prefab vs cut roofs
Then the trussed rafter arrived
on the scene and the centuries-
old skills of roof building were
seemingly swept away. House
roofs were reconfigured as a
series of thin prefabricatedimage: mitek
Design& Materials cutvSprefabvSpaneliSeD roofing byMarkBrinkley
From cut roofs to prefabricated trusses and panelised
systems, Mark Brinkley explains the options available to self-
builders and extenders and the pros and cons to consider
Choosing between
roof structures
Markbrinkley
is the author of
the ever-popular
Housebuilder’s
Bible and an
experienced
builder. He’s just
finished his latest
self-build projectprefab trusses made
offsite– withsteel
fastenerslikethese
manufacturedbyMitek
(www.mitek.co.uk)- are delivered and
installed creating a
web of timber trusses
that suit a simple-
shaped roof design.