Basement Waterproofing – Melbourne
Below Ground & Basement water leaks are expensive & complex to rectify.
Get Waterproofing Right at the Construction Stage.
Registered Building Practitioner & Specialist Waterproofer.
Basements Leaks & Waterproofing Systems
- The recent Australian construction boom has resulted in an unprecedented number of multi storey apartments & commercial construction.
- Many of these buildings involve basements for underground car parking, storage, and utility areas.
- However, an unfortunate consequence is evidence of an alarming increased frequency of building defects – and the most common of these defects is water leaks.
Read article HERE
- Of all the water ingress possibilities, the consequences of basement water leaks can be the most expensive and complex to rectify - often resulting in devastating & costly damage.
- For commercial buildings, water leaks can ruin expensive equipment and disrupt business while in the case of residential buildings this can result in damaged finishes and furnishings.
- Basement leaks add up to lost money, wasted time, upset customers and sometimes expensive litigation.
Leaking basements & foundations may comprise the structural integrity of the entire building structure.
Concrete & Basement Construction
Water & moisture is the source of most foundation problems and is the biggest factor in corrosion of basement reinforcing steel.
- Is Concrete Waterproof?
- Concrete is porous.
- Despite what many may think – concrete is NOT waterproof.
- Water can seep through perfectly intact concrete – given enough back pressure.
- Uncracked concrete - and what concrete is uncracked? - may reduce the movement of liquid water, however water vapor can still penetrate quite easily.
FREE BASEMENT WATERPROOFING GUIDE
This guide is based upon my personal experience as a Registered Building Practitioner specializing in waterproofing applications and with over 30 years in the construction industry.
Basement Waterproofing System
- Below ground waterproofing is as important as the very structural foundations supporting a building.
- Without the combination of sound footings and a waterproofed foundation, a building will deteriorate rapidly.
- Unlike other building components that might be designed to be replaced several times within the overall building lifetime, below grade systems need to be built to approximate the entire service life of a building.
- Below grade waterproofing systems often are inaccessible for repairs.
- This can be extremely costly if rectifications are necessary at a future date.
In some instances, it may not be commercially viable,
or even possible to fix or upgrade failed basement waterproofing systems.
How to Waterproof A Basement
Keeping basements dry requires the right waterproofing system.
To ensure water does not penetrate basements in new construction:
- Prevent water from moving through walls & draining away is essential to a successful below ground waterproofing system.
- Starting with construction of the slab floor / wall zone - these areas require a water stop for either tilt panels or block work.
- Include crystalline growth compound in the concrete pour of walls or as a fill-in for block work.
- Once walls are constructed, ‘tanking’ with a waterproofing membrane.
Prefer LIQUID MEMBRANES for below grade.
- Protect the membrane by installing a suitable barrier prior to backfilling.
- Essential to the defence strategy is good drainage, for which there are many design options.
- Allow sufficient ventilation.
- The waterproofing method used needs to last the expected life-time of the building..
Damp Proofing & Waterproof Paint
Do not confuse damp proofing with waterproofing !
- To permanently stop water and water vapor from entering foundation walls, you need to use a waterproofing membrane.
- Damp proofing is intended to keep out soil moisture, but not liquid water that enters a basement via penetrations, gaps, cracks, and holes.
Damp proofing is a very poor long-term waterproofing protection method
and rarely lasts more than a couple of years.
Note – we do not provide Damp Proofing when a waterproofing membrane is required.
- Waterproof paint is used more as a common do-it-yourself waterproofing method.
Waterproofing paint should be regarded as a cosmetic fix.
Exterior Basement Waterproofing
A true Exterior Basement Waterproofing System keeps water out permanently - and is not just a water management system.
- Aim is to totally waterproof the exterior walls of below ground structures & eliminate possibility of water penetration.
- Waterproofing product and method for basement waterproofing should have a lasting effect.
Components of an external below ground waterproofing systems
1. Basement Waterproofing will prevent water & moisture from moving through the wall.
2. Drains to control water away from the bottom of the foundation.
3. Robust protection of the waterproofing membrane.
1. Waterproof Membrane
- Externally applied basement membranes include traditional sheet, Torch-On and Liquid Polymer Coatings.
- Whatever product used, all external membranes require adequate access to the foundation base and external walls during construction.
- Careful detailing of any joints, penetrations and service ducts are essential.
This last point, unfortunately, is often overlooked!!
2. External Drainage System
- Purpose of exterior drainage systems is to create a permanent water flow away from the footings & foundations.
- Drains to control water away from the bottom of the foundation.
- Prevents water from accumulating and standing against the foundation.
- Runs to a point lower than the footings - allowing water to naturally gravity feed away.
3. Protection Board
- Robust protection board is an essential part to a basement waterproofing system.
- This protects the membrane before backfilling.
Liquid Waterproofing Membranes
Of the various waterproofing products available
our preference is LIQUID APPLIED MEMBRANES (LAMs)
Spray Applied Waterproofing System
- Excellent resistance to standing water & hydrostatic pressure.
- Robust compressive strength.
- Long term durable membrane.
- Flexibility & Elongation - will expand with the building envelope settles.
Advantages of Basement Liquid Waterproofing
- Spray application creates a seamless membrane – no joins or seams to come apart.
- Extreme expansion and contraction without cracking or becoming brittle.
- Liquid will seal around all concrete & blockwork penetrations, holes, gaps etc.
- Crack spanning capabilities to resist hydrostatic pressure.
- Applied to green (uncured) concrete walls immediately after forms are removed.
- Compatible with a wide range of drainage, protection, and insulation boards.
- Very rapid cure rates.
Interior Basement Waterproofing System
Internal Controlled Water Management is another waterproofing system for basements.
- Internal Waterproofing can be used alongside external systems - especially if a habitable room.
- An interior drainage system addresses hydrostatic pressure, or the pressure of groundwater forcing its way through the basement walls.
- A drainage piping is installed in the interior perimeter of the floor - routing water that enters the basement to a sump pump system that actively removes the water.
- A backup battery-operated sump pump is often recommended to prevent flooding of the basement during a power outage.
- Internal Systems are also an option for remedial basement waterproofing when it is not viable to excavate the external membrane.
Internal Basement Waterproofing - Controlled Water Management
Melbourne - Basement & Below Ground Waterproofing Contractors
Specialist Contractor & Registered Building Practitioner
Builders & Owner/Builders
For small retaining wall projects - please see DIY Waterproofing Here: