Total Installer May-June 2019

Fixings
DON’T GET IN A FIX ON PROJECTS
Andy Holland, Technical & Marketing Manager at Rapierstar, explains why frame fixings and
fasteners for repair should be chosen with care.
Fasteners used to manufacture and install
windows and doors are instrumental in how
well the installed product will look, function
and perform long-term. Choose them well and
you’ll save a lot of time and hassle, as well
ensuring high customer satisfaction ratings.
Two main methods are available to fix window and
door frames into the wall construction – fixings
with plugs and those that are plug-less. Both are
suitable for timber and PVC-U frames, with best
practice being to position fixings at 600mm
centres, with corner fixings being between
150mm and 250mm from external corners, and a
minimum of 150mm from the centre line
of a transom / mullion.
Go plug-free – but
choose carefully
Rapierstar advocates the
plug-free route for a number
of reasons. With its StarFix
fasteners, all that’s required is
a 6mm or 6.5mm pilot hole through
the frame reinforcement and brickwork
and the screw can be driven into place with ease.
It saves times as there is no need to drill to
accommodate a plug or anchor and plastic waste
is reduced too.
Not all plug-free fixings are the same, however.
When the screw is driven into the masonry, dust
and debris is produced which must go
somewhere, but it cannot if the
thread height is the same
down the length of the
screw. This can lead to
reduced grip as the thread
may end up simply cutting
into dust as the screw is
driven deeper into the masonry,
resulting in poor pull-out strength.
“Don’t be
tempted to
use any old
screw when
attending to
repairs!”
Choose ‘hi-lo’ for a secure,
distortion-free fix
The solution comes with a ‘hi-lo’ thread form. Here
the thread height varies to fulfil different roles –
the higher level thread cuts into the masonry and
the alternate low thread allows for dust
to be compacted. This is the
principle behind Rapierstar’s
Starform self-tapping thread,
used on all StarFix products,
which provides ultimate grip
and allows for multiple refixing
without stripping the
tapped hole.
The hi-lo thread form will also help to
avoid unreinforced PVC-U frames from ‘jacking’
or twisting as the frame fixing is driven through.
Some fastener threads may grip too much, and
this can easily cause distortion of the profile if it
lacks lateral rigidity in the absence of
reinforcement.
Fastener considerations for
window or door repairs
Don’t be tempted to use any
old screw when attending to
repairs! Windows and doors
must be repaired using
fasteners which are
consistent with the lifespan of
the window. For example, in
Contact Rapierstar
01260 223311
www.rapierstar.com
@Rapierstar
Left: Hinge fastener corrosion.
Middle: Rapierstar fasteners;
Bottom: StarFix fasteners.
coastal areas where the air
is salt-laden, a window’s
friction stays will need to be
held in place with austenitic
stainless steel fasteners to prevent
rusting. If that is replaced with a carbon steel
screw, a weak point will be introduced, and that
screw may rust in just a couple of years.
With PVC-U frames, remember to use a larger
fastener size than the one that it is replacing. It
may sound obvious, but we see examples where
this advice is not followed, making it difficult to
achieve a secure fix for handles, hinges and
locking systems.
Fastener guidance to help you get it right
Rapierstar produces Recommended Fixing Manuals
(RFMs) for all the major profile systems. These
easy-to-use guides show exactly which fasteners
to use to attach hardware, as well as when
coupling assemblies and installing bay windows.
And even if you face a situation that isn’t covered
by an RFM, there are more than 120 fastener
types available from Rapierstar alone, one of
which could be the ideal solution for whatever
fixing challenge you are facing. For example,
Rapierstar WSR self-drilling baypole fixings,
available in lengths from 50mm to 100mm, are
incredibly versatile and we know from feedback
that installers use them for many different
purposes, including when fitting cills.
46 TIJULY/AUG 2019 PRACTICAL CONTENT FOR THE GLAZING INSTALLER & HOME IMPROVEMENT SPECIALIST