Method of Cleaning and Maintenance

All operations to be undertaken by suitably trained personnel utilising appropriate safety methods and in accordance with proprietary manufacturer’s recommendations and instructions.

Any requisite repair/ making good work to be undertaken by Licensed sub-contractors only in accord with the following Sto Render Planned maintenance Guide.

Sto EXTERNAL RENDER SYSTEMS

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: 

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
increasing the likelihood of algae and fungal growth).

location          (city environments are more subject to pollution,
traffic grime, etc. than rural ones)

client               requirements.

 

B.        Frequency 

Taking account of the above noted variable criteria it is not possible to accurately determine a cyclic period for planned maintenance. 

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.         Surface soiling that can be removed by washing.

b.         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 water with the addition of a mild household detergent. 

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 coat of StoPrim Fungal  and allow to dry. Do not wash off. Apply one or two coats of Sto Lotusan G facade 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 StoRend External Render Systems 

Mechanical Damages

Method Statement 

a.        Material requirements

Levelling coat:     StoLevell Cote

Reinforcing coat: Sto Armat Classic

Reinforcing mesh: Sto Armor Mesh and/or Sto Reinforcing Mesh Fine

 Sto PVC Mesh Angle Bead or Sto Armor Angle

Decorative finish:  Stolit

b.        Repair procedure

The following procedures relate to isolated repairs in StoRend Systems. Depending on the specification of StoRend System used, not all of the steps listed below will
need to be carried out.

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. If the render
system incorporates a reinforcing layer then care should be exercised to avoid
damaging the reinforcing coat and mesh. 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. If necessary, carefully cut away the Sto Reinforcing Mesh to within 100mm from the edges of the existing Sto finish.

3. Remove the existing damaged render to expose the substrate. Clean and prime, if necessary, with the appropriate Sto product.

4. Before re-coating with any render material determine that the substrate does not require any repair procedure, e.g. if the substrate is cracked then additional repair procedures may be necessary. Sto Technical Department can advise.

5. Apply the appropriate levelling plaster over the area and leave flush with existing levelling coat. Allow to cure as appropriate for the material specified.

6. If the specification includes a reinforcing layer, cut a piece of Sto reinforcing mesh to cover
the area of repair 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 visibility of the repair. In this
case, please refer to the section headed ‘Cleaning of Soiled Synthetic
Resin Coatings’.