Waterproofing failure in buildings comes at a huge cost. One of the biggest mistakes people make in both residential and commercial projects is to try and cut corners (time and investment) by not using quality products. Oftentimes in building, it is what cannot be seen that is the most important to get right. It can be very costly to identify the source of water ingress and fix the problem, so it is crucial to follow safe practice.

When it comes to bathrooms, foyers, laundries, or kitchens, waterproofing is crucial and worth investing in so designers need to ensure they get the best advice, and if using a certified waterproofing professional, ensure they provide a waterproofing certificate and warranty after work is completed.

It is worth considering also that a waterproofing membrane is really only as good as the substrate that it’s sitting on. Without a good foundation, if the building moves later on, the substrate and linings could move, and the waterproofing membranes will break.

For more information on waterproofing in residential homes, download Tile Warehouse's Waterproofing Guide

Frequently Asked Questions:

Can homeowners waterproof their own bathrooms?

Water leaking into floor and wall spaces can rot structural timbers and cause damage, so all floors, shower enclosures, and areas around the toilet and bath need to be thoroughly sealed. For DIY advice, visit a local Tile Warehouse for assistance. For the full NZ Building Code, download the NZ Code of Practice building compliance document.

How long should waterproofing last?

If installed correctly to the NZ Building code, most modern, good quality, waterproofing membranes should last a minimum of 10 years, and likely much longer than that. For full warranty details, check with the nearest Tile Warehouse store or waterproof product supplier.

How can designers select the best waterproofing membrane?

This depends on the project — whether it will be residential or commercial and whether the homeowners have decided to do it themselves or get the professionals in. Whatever choices are made, designers should check with a Tile Warehouse outlet to ensure they have the correct materials and all the advice needed for a successful project outcome.

Tile Warehouse recommended Waterproofing Systems:

ARDEX WPM 001

ARDEX is a system solution provider of high-performance speciality building materials. For more than 60 years, ARDEX has been a quality leader for the flooring and tiling industries.

ARDEX’s premium waterproof product is the WPM 001, a tough, ready to use waterproofing membrane specifically designed for use under tiles. It has been uniquely formulated with synthetic microfibres to increase its strength and eliminate the need for a separate reinforcement mat. ARDEX WPM 001 is based on the most advanced acrylic polymer technology and is totally resistant to re-emulsification once cured.

ARDEX WPM 001 is one of the fastest drying one part acrylic membranes on the market. Download Technical Specification sheet

Hydrathene by Dribond Construction Chemicals

Dribond Construction Chemicals has been in business since 1974 and has grown into one of the most respected ceramic tile adhesive, waterproofing and repair product manufacturers in Australia, New Zealand, and Asia/Pacific.

Construction Chemicals' waterproofing product, Hydrathane is a one-part, water-based, polyurethane waterproofing membrane which is flexible, tough, and fast curing (capable of drying in 6-12 hours @ 23°C @ 50% relative humidity). The cured membrane will remain tough, elastic, and can bridge and seal hairline cracks. It is UV Stable, suitable for maintenance foot traffic, and does not stain tile, grout, or marble.

This waterproofing membrane can be used for all internal wet areas as well as screeded rooftops and balconies.

Note: For commercial projects, Tile Warehouse recommends the addition of Construction Chemicals LiquidFlash or Ardex sheet membrane products.