StoTHERM EXTERNAL WALL INSULATION SYSTEMS
StoTherm External Wall Insulation System
Planned Maintenance
A.
General Information
The advanced design and high performance levels offered by Sto synthetic resin based
External Render and Paint coatings ensure that
maintenance requirements are reduced to
an absolute minimum.
Sto products and systems are more resistant to soiling than most
traditional building
materials and their continued performance and
durability does not rely on periodic
maintenance. The need for cleaning or over-coating is usually determined by a degradation in
the aesthetic appearance of the facade caused by surface soiling and the Client’s
desire
for a fresh appearance. The rate at which soiling accumulates is dependent on a number of
local factors including:
B.
colour
(lighter shades show dirt more than darker ones)
texture
(the heavier the texture the more possibility for dirt
retention)
aspect
(north facing facades remain wetter for longer thereby
likelihood of algal and fungal growth).
increasing the
location
(city environments are more subject to pollution, traffic
ones)
grime, etc. than rural
client
requirements.
Frequency
Taking account of the above noted variable criteria it is not possible to
a cyclic period for planned maintenance.
accurately determine
High quality latex and solvent based paints would require re-coating
every 5-6 years.
StoSilco coatings are still performing after 15 years
without the need to re-coat. When
over-coating becomes necessary, renovation should be infrequent, quickly executed and
economical.
C.
Method Statement
Cleaning of Soiled Synthetic Resin Coatings
The removal of soiling can be divided into two categories:a.
b.
Surface soiling that can be removed by washing.
Surface soiling that requires overpainting.
Surface soiling removable by washing
1.
Light soiling may be removed by the use of a soft brush and warm
addition of a mild household detergent.
water with the
2.
Heavier soiling may require the use of a power washer, subject to the following rules:
Water pressure not to exceed 30 bar.
Water temperature not to exceed 30ºC.
Nozzle to be no closer than 500mm to the surface being cleaned.
Surface soiling that requires overpainting
After washing as above, apply one or two coats of StoColor Crylan or StoColor Maxicryl
acrylic resin paint, or StoSilco Color silicone resin paint tinted to the colour reference of the
original plaster if the same colour scheme is required or to any other colour if a change is
desired.
Repair Procedure for StoTherm External Wall Insulation Systems
Mechanical Damages
Method Statement
a.
Material requirements:
Insulant: expanded polystyrene to match thickness of original installation
Adhesive: StoLevell Uni - for masonry backgrounds
Sto Dispersion Adhesive - for board, plywood backgrounds
Sto Flexyl - for below DPC
Reinforcing coat: StoLevell Uni or Sto BTS/B or Sto RFP or Sto Flexyl
Reinforcing mesh: Sto Armor Mesh and/or Sto Reinforcing Mesh Fine
Sto PVC Mesh Angle Bead or Sto Armor Angle
Primer: Sto Primer ( only required with StoLevell Uni, Sto BTS/B and Sto Flexyl)
Decorative finish: Stolit or StoSilco or Superlit
b.
Repair procedure
The following procedures relate to adhesively fixed systems and for isolated repairs in
mechanically fixed systems.
Wherever possible ensure that the repaired area is finished to align with existing features such
as doors, windows, string courses, downpipes, etc. to reduce its visual impact.
1. Remove the existing Sto finish from the wall approximately 150mm beyond the damaged
area. Care should be exercised to avoid damaging the reinforcing coat and mesh in this
area. This may be achieved by grinding the surface with a suitable electric hand-tool or by
softening the surface with a steam stripper and carefully removing the finish.
2. Carefully cut away the Sto Reinforcing Mesh to within 100mm from the edges of the
existing Sto finish.
3. Cut away the damaged insulation leaving clean smooth sides to the hole formed.
4. Cut a piece of insulation to accurately fill the hole. Rasp the surface to achieve the correct
thickness.
5. Adhere the insulation in position with the appropriate adhesive for the substrate and allow to
set.
6. Cut a piece of Sto reinforcing mesh to cover the insulation and to overlap the existing mesh
by about 50mm on all sides.
7. Apply the appropriate reinforcing plaster over the area to be meshed and immediately
embed the pre-cut piece of mesh. Ensure the correct thickness of plaster is applied and
‘feather out’ at edges.
8. If required, brush apply 1 coat of Sto Primer when the reinforcing coat has fully dried.
9. Mask off the surrounding area of finish plaster.
10. Apply the decorative finish and texture to match the existing surface
finish.
The finish should be applied to within 5 - 10mm of the
surrounding finish and then
carefully ‘stippled in’ with a small brush to
blend the wet finish into the existing
surface.
NB
Due to normal colour variations between different batches of material and the effects of natural
weathering over a period of time it may be necessary to clean or overpaint the area or section
where the repair has been effected to ensure minimal visibilty of the repair. In this case, please
refer to the section headed ‘Cleaning of Soiled Synthetic Resin Coatings’.