|
Description
A cement-based mixture containing chemicals which combine with the water in cement and migrate into the concrete or cement plaster thereby effectively waterproofing the structure against hydrostatic pressure. For slurry coatings and plugging holes. Supplied in a dry powder form.
Purpose
For solving most types of waterproofing problems in belowground and water-containing structures.
Types
Supplied in one type only. Can be used in conjunction with Cemcrete’s Accelerator for sealing gushing leaks.
Colours
Supplied in grey or white.
Applications
Suitable for permanently waterproofing, in all climates, structures such as basements, cellars, reservoirs, dry docks, bridges, tunnels, sewers, hydro-electric stations, retaining walls, lift shafts, machinery pits, parapet walls, grain silos, underground in mines, magazines, subways, underground telephone structures, shower floors, roofs, rising damp, balconies, etc.. Can be effectively applied to outside or inside of structures.
Advantages
Penetrates capillaries of concrete effectively and permanently sealing them off. Protects against oil, salt water, alkalis, certain chemicals, weak acids and aggressive sulphate soils. Excellent adhesive qualities, used for bonding old and new concrete. Waterproofs from inside against hydrostatic pressure due to osmosis i.e. from high concentration of active chemicals to low concentration. Will increase strengths of concrete by up to 30% dependent on quality of original concrete. Waterproof but not vapour proof thus allowing the concrete to breathe. Non-toxic so can be used for potable water, even fish ponds. Resists water
pressure of up to 120m head. Chemicals remain dormant if no water is present but will start reacting again if water does come into contact with it at any time later. Cannot rupture or tear. Because Permastop is cement-based, its expansion and contraction is essentially as the concrete surface it is applied to.
Note
Does not react with clay bricks unless overcoated with cement plaster. Must be in contact with the cement/ concrete to be effective.
Specifying
“Cemcrete’s Permastop to be applied in two coats with a 150mm block brush. All suspect moving joints or cracks to be repaired using “Joint Filling Mix” incorporating Permastop and covered using polypropylene membrane saturated with Permastop. Surfaces to be prepared in accordance with manufacturer’s instructions.”
Specimen Finish
A trial area should be treated on-site for the Engineer’s or Architect’s approval and to serve as a specimen to which
Contractor should work.
Site Work
Storage
In unopened drums shelf life is at least 12 months.
Surface Preparation
Surfaces should not have been previously painted. (If they have, see 1 below). They should be firm and free from loose material, mould, oil or grease. Organic growths should be removed by brushing with a solution of 1 volume household bleach (sodium hyperchlorite solution) and 3 volumes water. Allow 12 hours to kill spores then remove with a wire brush and water. This should be followed with an acid wash comprising a solution of 1 volume hydrochloric acid and 3 volumes water. Apply the acid solution using a white wash block brush from a plastic bucket and allow to react for at least 10 minutes then wire brush and flush with clean water. Projections should be chipped off and all cracks and joints cut out square and made good with “Joint Filling Mix”
|
mixed as under. The concrete should be thoroughly saturated with water before application to aid in the passage of the chemicals through the capillaries of the concrete. Allow the surface to partially dry out then apply Permastop. 1 If surface has been previously painted it should either be bush hammered or sand blasted to totally remove all traces of previous coatings.
Mixing
Slurry : To one volume water stir in two volumes Permastop. Keep stirred and use all mixed material within 20 minutes. Do not add water to mixed material to restore workability. Joint Filling Mix : Mix one volume Permastop with one volume clean plaster sand and bring to a thick plaster consistency with clean water.
Membrane : Mix as in slurry and dip membrane in slurry to completely impregnate membrane.
Application
Slurry : To the damped surface brush on a liberal coat of Permastop using a 150 mm block brush or a large distemper brush. A soft broom may be used for application to floors. If two coats are applied the second coat should not be commenced until the first has set for 30 minutes but no later than 90 minutes after the application of the last coat of Permastop. We recommend a plaster or topping mix comprising either Cemcrete’s Water Repellent Cement or at least Cemcrete Waterproofing Compound. Joints : To cleaned out joints/cracks apply one coat neat slurry mix then within 90 minutes fill with “Joint Filling Mix” above. Membrane : Lay impregnated membrane over area to be covered and use paint brush to smooth out and flatten membrane.
Gushing Leaks : Open concrete at place were water is pouring out to a cavity of about 40 mm3. Grout in place a piece of old hose pipe using “Joint Filling Mix” mixed with Permastop Accelerator instead of only water. Once water has been lead away from surface of concrete, continue to waterproof rest of concrete. When set and all is waterproofed except water flowing from pipe, remove pipe by twisting and immediately
fill with a plug of jointing mix mixed with the accelerator. Use rubber gloves if contact with skin is expected.
Curing
In hot dry conditions cure completed work by damping with clean water three times during the day following the day of application. Protect against freezing for 24 hours. Protect from direct sun and wind by covering with plastic or wet hessian for 24 hours.
Painting
If Permastop is to be subsequently painted, it should be cured by wetting for at least 15 days. Neutralise by applying to surface a mixture of 8 volumes water and 1 volume hydrochloric acid or vinegar. Allow to react for 15 minutes. Rinse thoroughly, allow to dry, then paint.
Coverage
Brush application : Approximately 1,3m2/kg/coat depending upon suction and texture of surface.
Joint filling : Depends on size of joint. With polypropylene membrane : Approximately 3 kg/m2.
Packaging
Permastop : In 1 kg, 5 kg and 25 kg non-returnable drums.
Accelerator : In 1 litre, 5 litre and 25 litre non-returnable drums.
Membrane : In 100 mm x 10m and 1000 mm x 10m lengths.
Always wear gloves when applying Permastop
|
Cemcrete Products 
