Hep20 Technical Handbook

2. Fix each conduit pipe to noggins
using suitable straps or cable
ties. Fixings at 1m centres are
adequate for vertical conduit
pipe. Horizontal runs and bends
more than 45° should be
avoided.
3. To allow future installation of
drylining boxes, each conduit
pipe end should be left
approximately 100mm longer
than box position and should
not be fixed closer than 600mm
to the box.
4. Install the main ‘first-fix’
pipework leaving joints below
floor access covers to allow
connection to conduit pipework
during ‘second fix’ work.
5. Using setting-out dimensions on
sketches, holes in plasterboard
can be cut to allow each conduit
pipe to be pulled out through
the surface during plasterboard
fixing work.
6. During ‘second fix’ each dry
lining box is installed by drilling a
26mm diameter hole for 15mm
(nominal) conduit pipe. The
conduit can then be inserted
through hole in box and should
‘click’ into position leaving one
or two conduit ‘ribs’ inside box.
7. Slide a length of 10mm Hep 2 O ®
pipe through conduit pipe from
the floor access above. Pull out
enough Hep 2 O ® from drylining
box to allow a sufficient hand
grip for jointing. Connect a
demountable elbow to pipe then
slide whole assembly through
plasterboard hole and secure
box into position. Conduit pipe
should ‘snake’ within void to
take up slack leaving Hep 2 O ®
protruding out of box.
8. Pull Hep 2 O ® pipe backwards
from floor access panel until
elbow is central within dry lining
box. Cut pipe to length and
connect to Hep 2 O ® joint left
during ‘first fix’.
General advice on timber or
steel framed buildings
Holes through timber joists should
be drilled in accordance with
Figures 16 & 17, on page 65. Holes
through timber studs should be
drilled in accordance with Figure 30.
Within steel framed buildings
pipework should be routed through
preformed holes in steelwork
wherever practicable (and where
provided). No holes should be
formed in steelwork without the
approval of the Architect. Pipework
passing through steelwork should be
protected from damage. Refer to
‘Pipes Through, and Adjacent to,
Metalwork’ on page 69. Do not lay
pipework in areas where
plasterboard is likely to be fixed.
Services within compartment or
party walls should be avoided so as
not to impair fire resistance or
acoustic properties.
Care should be taken that pipework
passing through compartment
walls or floors does not impair the
fire resistance of the property.
10mm Hep 2 O ®
Plasterboard
15mm (nominal) Conduit Pipe
firmly terminated within
drylining box
(When cutting vapour control
plasterboard around drylining
box, care should be taken not
to displace vapour control
material)
100mm Hep 2 O ® Single Socket
SlimLine Elbow (HX4/10)
Demountable Elbow (HD5/10)
Drylining box and cover plate
(single gang electrical fitting)
Insulation
Holes should
be located in
these zones
and drilled at
centre of
stud depth
Figure 29
Radiator connection using 10mm Hep 2 O ®
within a timber or steel framed external wall
0.25 x H
Figure 30
Limitations of drilling studwork
D
0.25 x H
Max dia of holes = 0.25 depth of stud ‘D’
0.4 x H
Stud height ‘H’
0.4 x H
79