SpECbond PVA can be used as a multi-purpose
adhesive, primer, sealer and admixture for cement
systems.
· Versatile and economical.
· Quick drying high strength adhesive.
· Excellent shelf life under normal conditions.
· Conforms to British Standard 5270.
Preparation
To achieve results it is important that preparation
is carried out thoroughly. Although SpECbond PVA
has exceptional adhesive properties it will not
perform efficiently on contaminated surfaces.
Remove all flaking and cracking paint, unsound
plaster, oil, grease and friable matter to provide a
stable substrate. Highly absorbent surfaces such as
Concrete, Foam and Slag blockwork may require
pre-wetting before application of SpECbond PVA
sealer. Please note that PVA should not be used
as a bonding agent where wet conditions are
continuous or in highly humid areas – see data
of SpECbuild BA10.
For use as an adhesive
When bonding wood to wood apply a thin coat to
one face only and press together firmly. On large
surface areas, certainly with laminated plastic,
clamping or weights may be required for up to 24
hours. Very porous surfaces will need to be primed
with 1 part SpECbond PVA diluted with 3 parts
water and allowed to dry before carrying out the
adhesive operation. It is not recommended that
unmodified SpECbond PVA be used for gap filling
where gap filling in necessary perhaps in the
bonding of plasterboard, polystyrene, acoustic
board etc., a suitable filler should be used to
modify SpECbond PVA. Mixing equal parts with
water and adding fillers such as plaster, cement,
fine sand or sawdust would accommodate the gap
filling requirement – consult our Technical Services
Department if a detailed specification is required.
For use as a plaster, cement/sand render &
screed bonding agent
Normally, on most surfaces, no mechanical hacking
or keying is required before application of gypsum
plaster. Mix SpECbond PVA with an equal part of
water, apply to prepared substrate and allow to
become tacky before plastering in the normal
manner. For heavier rendering using sand/cement
systems, seal and prime as above but employ an
intermediate bonding slurry prepared by mixing 1
part ordinary Portland Cement with 1 part
SpECbond PVA to 3 parts water. Apply the slurry
to the still tacky primer with a stiff brush to achieve
a rough surface or stippled surface. Allow to
harden, check adhesion to substrate and apply
rendering. When rendering on glazed tiles or highly
polished surfaces it is suggested that light pick
hammering should be carried out before following
the above recommendations.
For use as an admixture in cement/sand or
granolithic screeds
This incorporation of SpECbond PVA allows for
reduced thickness floor screeds to be laid without
recourse to setting out bays. The ability to lay at
reduced thickness enables the operator to redress
unacceptable differences in levels but resolution of
these levels should be confined to between 9 to
19mm thickness of screed.
Areas subjected to light traffic should be primed as
recommended and screeded with a mix of 3 parts
sharp sand, 1 part cement and gauged with 8 litres
of SpECbond PVA per 50 kg of cement.
Where heavy traffic is envisaged use a mix of 1
part sand, 1 part cement and 2 parts granite (6 to
3mm) – gauge with SpECbond PVA at the rate of
10 to 15 litres per 50kg of cement and add a little
water if necessary but this type of screed should be
mixed semi-dry, never overwet. Lay the screed on a
tacky bonding coat, tamp and trowel to a smooth
finish. SpECbond PVA/sand/cement screeds can
normally be opened to light foot traffic in 36 to
48 hours and granolithic 24 to 36 hours. Before
opening to heavier traffic allow 3 to 7 days
depending on the type and weight of traffic.
For use in repairs to concrete
Prepare damaged or worn concrete as recommended and attempt to cut-back perimeter edges of the
area to minimise the necessity for
feather-edging’. Prime with equal part SpECbond
PVA and water and repair whilst primer is still tacky.
The repair mix should consist of 1-part cement and
2-part sand gauged with a mixture of 1 part
SpECbond PVA to 3 parts clean water. Compact
firmly but do not over-trowel.
Supplied in 5 litre, 20 litre and 200 litre units.
When used as an adhesive, coverage will vary
according to the degree of porosity of the surface to
which SpECbond PVA is applied but the following
average will provide a guide.
Undiluted: 9 m²/litre
Diluted 1:1 : 20 m²/litre
Diluted 1:3 : 32 m²/litre
Contact us for more info.