Are you building an office block
or car park and using flat concrete for the roof, and struggling
to find the best form of insulation that will also eliminate
condensation, and will bond straight to the concrete without
the hassle of fitting panels?

‘Webtherm’ and ‘Pirthane’
are both rigid polyurethane foam systems designed for spraying
onto the underside of concrete, and can be applied astonishingly
neatly, ideal if the roof will be open and seen by the general
public etc.
We are one of the market leaders
currently applying the Pirthane system, and come strongly recommended
by the suppliers, Isothane Ltd, based in Accrington, Lancs.
The Pirthane concrete insulation system gives a fire protection
rating of class zero, achieved by first applying a layer of
Pirthane HR foam followed by two coats of an Intumescent coating
available in either White or Light Grey, to also give an aesthetically
pleasing finish to the surface.
Imagine the hassle of cutting
and fitting insulated boards to the underside of particularly
large spans of flat concrete, not to mention the wastage involved,
when compared to our highly trained and experienced engineers
simply turning up, and spraying the insulation in place to any
desired thickness, to achieve a near perfect flat finish, we
think you’ll agree with us when we say spray foam concrete
insulation is the way to go.
Besides Pirthane we offer our
standard product, which is the WebTherm class one rigid foam
concrete insulation, sprayed in the same way except obviously
being rated at class one, not class zero. The colour of the
foam is almost magnolia, though we can quote for applying almost
any coating underneath the foam, from simple matt emulsion right
up to impermeable chlorinated rubber coatings, available in
a wide range of colours.
If the insulation is to be left
exposed inside a roof or wall space, do not worry, our insulation
can be painted in water based emulsion to all RAL numbers. This
is a service Websters Insulation can quote for and is applied
by our own highly skilled engineers.
With a portfolio boasting the
likes of IKEA (Coventry), ASDA (Harlow, ESSEX), Carillion (Doncaster
Lakeside Keepmoat Stadium, Glamorgan County Cricket Club, Cardiff),
Balfour Beatty (Metronet Rail Depot, London), Banner Holdings
(Arundel Gate office block, Sheffield), you can be sure our
experience will benefit you above all competition. See the case
studies below for problems that were brought to us to seek a
solution to…
Case Study One:
IKEA, Coventry
We were contacted by a company called Underwood Carpenter, with
the task of quoting for and applying the Pirthane Class 0 system
to the underside of over 1500 square metres of flat Bison concrete
planks, located in numerous places on site. The bulk of the
work lay in insulating the soffits, to which we first applied
a coat of PVA concrete bonding primer followed by a 55mm thickness
of Pirthane HR Foam and two coats of water based intumescent
FPC as part of the Pirthane system. The result was an astonishingly
neat finish that met the specification perfectly, and also led
to us doing more work within the same building, both insulation
work and specialist paint coatings (applying an intumescent
‘egg shell’ coat to much of the surrounding steelwork).
Case Study Two:
ASDA, Harlow, Essex
We were approached by DCI Refrigeration who were in a small
predicament. An underground concrete roof at the ASDA store
in Harlow was seriously condensating, and a large amount of
black mould had formed as a result of this condensation. Our
solution to this was to totally scrape off and remove the mould,
which we did ourselves, and subsequently apply a 50mm thick
layer of Class One Webtherm insulation to all underside areas
of the newly cleaned flat concrete. Besides adding a decent
level of insulation, this method is also guaranteed to eliminate
condensation for the life of the building.
Case Study Three:
Osborne Developments, Granville House, Surrey
We were contacted by Osborne Developments, who were building
a large pool house from concrete and required the whole underside
of the flat concrete ground floor roof insulating. Not won over
by the idea of panels, they called us for advice, and we came
up with the following solution:
We firstly applied a layer
of PVA concrete primer to the whole underside of the roof area,
then a vapour check barrier using a chlorinated rubber coating
followed by 50mm of Class one Webtherm spray foam and a final
vapour barrier, again using the chlorinated rubber coating.
The system we proposed worked perfectly, and ensured water vapour
given off from downstairs couldn’t come into contact with
the concrete ceiling, and the insulation prevented any cold
bridging through the concrete. We also insulated the steel uprights
to prevent condensation forming once they’d been cladded
over.
Call now on 01405 812682.