Designing Cementitious Basement Waterproofing of a building starts at the basement and finishes at the roof of the building.
The initial waterproofing of a basement is a crucial part of waterproofing preventing water penetration of the wall structure. Like waterproofing lift wells or pits they are an integral part of a building whether it’s for a livable area or a basement carpark. The consequence of a waterproofing failure of the basement will cause damage to the structure:
- of the wall weakening the walls & reducing the longevity of the structure, even collapse of the wall over time.
- causing the rusting of the steel re-reinforcement – which can increase up to 8 times its original size
- mold & fungus inside the basement & resultant health issues
- higher maintenance costs
- timing of the application
The use of Aggie pipes in many cases is moot. There is often not enough room to place the Aggie pipe in a suitable location and the Aggie pipe works by draining water away from the structure. This assumes the pipe drains somewhere and continues to drain water away from the wall for the life of the structure. The complexity of such a system which will not to clog, wash soil away from the footing and the like is difficult at best & seems to perhaps be an expensive sand filter at best.
- Cementitious Waterproofing Membranes are ideal in the new construction as they are in a renovation waterproofing job. The reason our team believes they are best below grade (ground Level) membranes is
- using adhesive based sheet membranes or liquid-based membranes usually requires completely dry concrete surfaces. Which is very difficult to achieve.
- a single pinhole will cause delamination of the membrane over time.
- Damage caused by the trades in the construction process, drilling through the membrane, for pipes, electrical all causing possible breaches. These breaches of the integrity of the original waterproofing membrane are often difficult to repair once installed.
Undetected pinholes. Breaches caused by other contractors completing works left unsealed. These will allow water entry points into the structure from the start. This is the commencement of the total delamination process for the membrane in the future.
That’s why cementitious waterproofing membranes like Drizoro Products (Drizoro Maxseal Flex | Drizoro Maxseal Foundation | Drizoro Maxseal | Drizoro Maxjoint Elastic) are not only adhered to the cement or concrete surface. They become part of the original surface and will not be pushed off (provided that the application was correctly applied).
Pinholes become self-healing and protrusions created by the trades can be sealed around by putting a coving around them with Drizoro Maxrest and then sealing around it with Drizoro Maxseal Flex.
Waterproofing Structures on the exterior or positive side of the Basement Wall
Drizoro Basement Waterproofing Materials required:
- Prepare the areas to be treated by removing any loose materials any efflorescence ensuring the surface is clean and sound surface.
- Any damage to the surface should be repaired using Drizoro Maxrest.
- Any missing mortar can be replaced with either Drizoro Maxrest or Drizoro Maxplug
- Apply Two coats Drizoro Maxseal Flex X 150mm cover over footing & wall joint incorporating Drizoro Maxmesh into the first coat
- Allow 14 hours minimum between coats.
- Two coats of Drizoro Maxseal Foundation | Drizoro Maxseal can be applied to all other rigid surface are as of the wall, 50mm overlap onto the cured Drizoro Maxseal Flex
- Leave 4 to 7 days before backfilling if required
- If rain is expected within 5 hrs do not apply.
- If a backfilling time is an issue, It is suggested that the coating be an applied as the wall is being constructed.
- Do not place plastic membrane or the like immediately after coating.
- Any external penetrations require Drizoro Maxplug and a coating of Drizoro Maxseal Flex incorporating Drizoro Maxmesh
Interior Cementitious Basement Waterproofing
The refurbishment of external basement waterproofing is difficult, if not impossible, and the cost is usually enormous. Excavation, making the excavation safe.
- a persistent musty smell
- dampness in the wall
- presence of mold – not healthy
- effervescence salt build-up
- changes in the water table may cause seepage of leaking
Before attempting expensive repairs a check to see if it’s just condensation on the wall rectified simply by dehumidifying the basement area. Not having the correct run off away from the walls may be a problem in high rainfall areas.
No matter what arises to cause the problem of a damp or leaking basement. To prevent worse problems from developing, the best way forward is to fix it is to seal the wall completely using Drizoro Products Drizoro Maxseal Flex | Drizoro Maxseal Foundation | Drizoro Maxseal | Drizoro Maxjoint Elastic which can seal even high hydrostatic water pressure. Many recommend the use sump pumps but according to David Cook’s
“This is a very common yet misguided solution that is used all over the country. The idea behind fitting a sump pump is born out of ignorance, the “you can’t stop it, pump it out” mentality is steeped in danger!”
In the first instance, you need to break into a reinforced concrete base that has been specifically designed to take the loading of the ………….buildings walls …and possibly other areas of the building. This raft WILL NOT have been designed for someone to come along and cut a hole into the concrete which will invariably involve exposing the steel reinforcing or worse cutting through it.”
Specifications for Cementitious Waterproofing of Basements with Hydrostatic Pressure
Basements, Retaining Walls and Tunnels to prevent the ingress of water due to hydrostatic pressure.
Drizoro Basement Waterproofing Materials required:
- If water is flowing on the surface of the wall then it may be necessary to drill holes or chisel loose mortar lines especially at the base of the wall to allow water to drain from the face of the wall surface.
- If rendered remove all render and paint.
- At the floor-wall joint chisel open floor-wall joint to prepare for a coving. (All cracks & joints should have a minimum depth of 2 centimetres and an opening of 1.5 to 2 centimetres. Make a square-shaped cut. Preferably equally into the floor and slab; avoid the “V” shape)
- Prepare the area to be treated by removing all loose materials and efflorescence ensuring a clean and sound surface. (Note:-efflorescence my grow back in a 24hour period if necessary the use of Efflorescence Rid is recommended)
- Apply a single coat of Drizoro Maxseal Foundation at the prescribed rate to the entire wall including cracks, mortar lines, floor slab wall joint. (Note:- NO water flowing on the wall face – may still be flowing from floor-wall joint or any drilled holes)
- Allow overnite curing of the first coat of Drizoro Maxseal Foundation. Where ever there no water flow from prepared holes & cracks fill these with Drizoro Maxrest. Where water is flow is present use Drizoro Maxplug to halt the water flow (use as per technical bulletin)
- To the coving at the floor slab wall intersection apply to damp surface 150mm vertically from the joint using Drizoro Maxseal Flex and return to slab 150mm incorporating Drizoro Maxmesh into the initial coat (this method to be used for all cold, construction and dummy joints)
- If pinholes of water are visible after 14 hours after the first coat, drill and plug area with Drizoro Maxplug until the area is dry
- Apply the second coat of Drizoro Maxseal Flex to the joints
- Apply the second coat of Drizoro Maxseal Foundation or Drizoro Maxseal onto the remaining rigid damp wall (or damp surface as necessary) surface area of wall overlapping Drizoro Maxseal Flex by 50mm. If further leakages are notable repeat procedure at point 4 above
- Minimum of 14 hours before rendering, 7 days before painting
- If the surface area has a low porosity value Drizoro Maxseal Flex should be used in place of Drizoro Maxseal Foundation or Drizoro Maxseal
- If excessive amounts of salt are prevalent on the structure do not use Drizoro Maxseal Foundation or Drizoro Maxseal in these areas. Please refer to efflorescence specifications treating-efflorescence-salts-for-adhesion.pdf (also see Efflorescence Rid)
- Use this information in conjunction with the appropriate technical data bulletins.
Note Regarding Cutting Holes in Below Grade Slabs for Sump Pumps:
Whilst the OnlineWaterproofingShop Team believes the keeping water out and away from a structure is the ideal or best solution it is not always possible and the presence of a sump pump in a basement will create a weak point for water entry and allow the presence of a dampness for mold to grow.
The idea behind fitting a sump pump is born out of ignorance, the “you can’t stop it, pump it out” mentality is steeped in danger!
To do this you will first need to break into a reinforced concrete base. That has been specifically designed to take the loading of the lift mechanism, the actual lift shaft and possibly other areas of the building. This raft slab WILL NOT have been designed for anyone to come along and cut a hole into it. This invariably involve exposing the steel reinforcing or worse cutting through it.
Far better to lock out the water from the structure from the positive or water side. However if this is not possible then the negative side waterproofing is still a better solution than doing nothing.
When your membrane fails on the water side and it isn’t possible to relieve hydrostatic pressure. Watch how a dry wall is achieved with Drizoro Products in the video below
Waterproofing Membranes for Basement Walls
- Drizoro offer the best cementitious basement waterproofing materials. We recommend cementitious basement waterproofing materials to prevent further damage to the building structure. This removal of moisture from the structure and the internal basement wall will improve your health or even to add an usable extra room to your house.
Cementitious Basement Waterproofing uses a number of Concrete Repair Mortars.