As the UK's leading multi-storey and rooftop
car park renovation specialists, USL StructureCare are frequently
asked to inspect and advise upon mastic asphalt wearing surfaces.
These surfaces of course vary in terms of their condition and this
will ultimately determine whether over-coating with a lightweight
proprietary waterproof coating is feasible.
Over-coating mastic asphalt presents a very different
set of challenges to the more common concrete substrate, and it is
important to remember that many liquid applied coatings may NOT be
compatible and may even have a detrimental effect on the asphalt
Image showing rucked asphalt due to incompatible
The Eastgate Centre in Gloucester, currently being
refurbished by USL StructureCare, represents an excellent example
of a current asphalt over-coating project, and one which
demonstrates USL's leading position in this niche market
Image above of Eastgate Centre before works
Initially, USL liaised closely with BASF, one of the
worlds largest construction chemical businesses, and together the
two companies prepared a detailed and bespoke specification on
behalf of the client based on the EN 1504 accredited Masterseal
Traffic 2205 system. Having secured the project after a competitive
tender process, USL then took possession of the site in March
With isolated areas of the asphalt being in poor
condition (e.g. cracking, blistering and tyre indentations), patch
repairs were required to render the substrate suitable for
over-coating. A critical stage of the project saw the numerous tyre
indentations 'levelled' using a suitable and asphalt-compatible
repair compound, which, when utilised alongside surface preparation
works, leaves the substrate level and far more uniform in readiness
for the lightweight waterproofing.
Image above shows tyre indentation
On a phase by phase basis, the USL operational team
then began to install the Masterseal Traffic 2205 system, beginning
with the Mastertop P660 primer which is broadcast with a filler
aggregate to leave a light even cover. This step of the
installation process also allows any significant dimpled/crimped
areas of asphalt to be significantly reduced.
Image of primed deck
Once the primer has fully cured, the high performing,
crack bridging and spray applied Masterseal M800 waterproof
membrane is installed, to leave a completely watertight and highly
flexible layer. The membrane is also spray applied to all details
ensuring a homogenous and monolithic finish is achieved. Once
cured, an M880 wearing course is then applied including a further
broadcast of aggregate, and finally top coat TC681 is applied as
the final finish coat.
At Gloucester, the TC681 top coat is being applied in
contrasting grey colours to create the 'pad' effect. The 'pad'
layout, made popular by Q-Park, provides a very professional
looking car park surface, and avoids the use of white lines to
define parking bays. As well as eliminating the use of white lines
(which can often be an on-going maintenance item), vehicles park on
the pads themselves, meaning any oil/fuel stains are masked by the
dark grey deck coating.
Images above of finished deck at Eastgate
Of course, many clients opt for the introduction of
bright and vibrant colours as part of their car park refurbishment
project, and USL have experience of numerous colour combinations.
However, the most important consideration before embarking on your
asphalt over-coating project is to ensure that the coating being
considered is fully compatible with the asphalt, can demonstrate a
decent track record and is accompanied by a meaningful and robust
materials and workmanship guarantee.
We'd be delighted to assist you with your car park project,
please get in contact and one of our experts will happily discuss
your requirements firstname.lastname@example.org