ALUMI N IUM
Rational thinking in aluminium
With an increasing number of aluminium systems, GGP Magazine asks Sternfenster’s Mike Parczuk if the
proposition is becoming too complicated for the end-user.
The growth seen in sales of aluminium
bi-folding and inline sliding doors prelockdown
was exponential. Before
COVID-, The Window, Door and
Conservatory Markets in Housing in Great Britain,
by Palmer, was tracking rapid growth in aluminium,
with strong consumer demand for ‘fold and slide’
doors leading to a wider pull-through of product
including aluminium windows, entrance and inline
This includes growth at the last count of
volume terms and installed value by
to an increase in not only residential demand for
aluminium products but commercial and new
“Aluminium has been one of the biggest drivers
of industry growth,” says Mike Parczuk, managing
director of Sternfenster. “That’s why we’ve seen
a lot of new market entrants at systems level
and in fabrication. I fully expect that growth to
continue in the longer term as we come back from
COVID-. What I do think needs to change is the
complexity of aluminium supply – and that’s what
we’ve tried to do.”
INVESTING IN ALUMINIUM
Aluminium is a big part of Sternfenster’s offer,
with bi-folding and inline sliding doors, plus
commercial and curtain walling from Smart
Systems, making up a key element of a wider
product range that includes PVC-U systems from
Deceuninck, Residence Collection and Spectus.
It has also invested ‘big’. This includes £.6m
on a dedicated aluminium manufacturing facility in
, including a ,ft2 shop-floor footprint,
plus ,ft2 of office space.
It includes a state-of-the-art FOM LMT cutting
and machining centre – and, highly unusually – its
own powder coating line.
Combined, and with the investment that
Sternfenster has also made in its in-house IGU
business, the fabricator can offer its range of
Visoline aluminium bi-folding door, manufactured
in the Smart Visofold System, and inline sliding
doors fabricated in Smart Visoglide, glazed and in
any RAL finish, in -days or less.
Mike, however, argues that aluminium window
supply is for much of the industry, a more complex
(and he argues artificially so), proposition.
Sternfenster’s own aluminium window offer was
previously built around the Smart Alitherm 6
and Alitherm 8 ranges, but has been redefined
to focus on the Smart Alitherm system.
“After we moved into our new aluminium
factory in January
, our aluminium business
grew exponentially. And what we did was to fall
into the trap of trying to be ‘all things to all men’,”
“With a PVC-U window, there’s a limited
number of outer-frames, a limited number
of sashes, a limited number of beads; with
aluminium, because the costs of coming up with
a new dye are so low, systems companies don’t
really withdraw anything and so there are literally
thousands of variations.
“In our aluminium window business, we were
getting customers saying ‘can we have that sash,
with that mullion in that outer-frame and that
bead’, and we were saying ‘yeah of course you can,
no problem’ because we always want to deliver a
“And then, before you know where you are,
you’ve got too much stock, and you can’t control
it. Launching the Smarts Alitherm was all
about product rationalisation.”
Alitherm from Smart Systems offers a high
degree of design flexibility, suitable for residential
and light commercial installations with side and
top hung options. An extended polyamide thermal
break means that it achieves a WER A Rating or
‘U’ value as low as .¤W/m2K.
Maximum sash widths and heights of side hung
casements are mm x ,§mm; and ,§mm
x ,mm top-hung.
Mike argues that this rationalised offer has
meant that Sternfenster’s proposition to the
installer and, in-turn their homeowner customers,
is as a consequence far simpler, something which
he says delivers benefits to installers.
“Launching the series was all about
rationalisation. Taking complexity out of the
supply chain. So, it effectively replaced the
Alitherm 6 and Alitherm 8.
“The Alitherm ticked all the boxes for
security, for thermal efficiency, and it was a very
good mid-window between the 8 and the
6,” Mike says.
KEEP IT SIMPLE
Before making the switch to its new offer in early
, Sternfenster polled its customers on their
preference. This revealed that installers saw a
broad range of options as too complex, confusing
the proposition to the end-user.
“It turned out that our customers didn’t really
mind what we sold, we were just selling an
‘aluminium window’, and they were just selling ‘an
aluminium window’ and the end user didn’t really
know what they were getting,” Mike says.
“The more complicated we made it, the more
our customers had to remember, the more
questions we got asked, when nobody really
“And that’s the point, we have a role to lead,
and the end-user, as long as we do a decent job
in manufacture, in installation, is quite happy to
be led. With aluminium it’s about the material,
we very rarely get asked about SBD, or thermal
efficiency – for the majority of end users, Mrs
Smith, it’s, ‘I want to have aluminium’ and that’s as
far as they go.
“If it’s a high-end installation in a self-build or
coastal retreat, for Mrs Hubbard-Smith, then it
may be slightly different, but that’s the minority,
not the majority of installations.”