High-Use Rooms Built to Last
Bathrooms and kitchens are the most-used rooms in your home. They are also the most likely to fail when renovated poorly. The failure is usually invisible: waterproofing applied over an uneven substrate, tile grouting used as the primary moisture barrier, or shower trays without a compliant fall to the drain.
Builders Waikato applies rigorous technical standards to every bathroom and kitchen we renovate. Brad does not sign off until the wet-area waterproofing is correct and verified.
Who This Service Is For, and Who It Is Not
This service is for:
- Homeowners with an outdated bathroom that leaks, moulds, or fails to function safely
- Families who need a second bathroom added to an existing home
- Homeowners wanting to increase property value with a quality kitchen or bathroom before a sale
- Those whose current bathroom or kitchen was built without compliant waterproofing (common in pre-2000 renovations)
This service is NOT for:
- ✕Homeowners wanting the cheapest possible price with no regard for waterproofing standards: budget shortcuts in wet areas always cost more to fix later
- ✕Cosmetic-only refreshes, such as re-grouting, painting, or new taps
The Technical Standard We Work To
Wet-area waterproofing
All shower enclosures, bath surrounds, and wet floors are waterproofed to AS/NZS 3740 and NZBC E3/AS1. This means:
- Substrate preparation to remove dust, oil, and unevenness
- Reinforced waterproofing membrane applied at correct coverage rates
- Membrane taken up walls to the correct height
- Inspection of the dry membrane for holidays and coverage before tiling
Subfloor condition
Before any new floor covering goes in, we inspect the subfloor for rot, moisture damage, and levelling requirements. Renovating over a compromised subfloor is how expensive callbacks happen.
Licensed trades
All plumbing and electrical work is carried out by licensed practitioners. We do not use unlicensed trades on restricted work.
What Our Renovations Cover
Bathrooms:
Full strip to framing, subfloor assessment, AS/NZS 3740 waterproofing, tiling, vanity, shower, bath, fixtures, and licensed plumbing
Kitchens:
Full strip-out, layout planning, custom joinery supply and install, stone or laminate benchtops, splashback, and trade fit-out
Combined projects:
Bathroom and laundry combos, kitchen and dining improvements, and whole-home wet-area upgrades
Consents:
Like-for-like replacements generally exempt; service moves and new wet areas require consent: we advise clearly
Indicative Renovation Cost Ranges
- Bathroom renovation, standard, like-for-like$18,000 to $35,000
- Bathroom renovation, full layout change, new wet area$35,000 to $60,000
- Ensuite addition, new wet area in existing space$40,000 to $75,000
- Kitchen renovation, standard, similar footprint$25,000 to $55,000
- Kitchen renovation, full layout change, island$50,000 to $90,000+
Moisture Management in Older South Waikato Homes
Older homes in South Waikato present a specific set of moisture and water pressure challenges that make compliance with AS/NZS 3740 and NZBC E3/AS1 not just a technical requirement but a practical necessity.
Timber subfloors and historical moisture damage
A significant proportion of homes in Tokoroa, Putaruru, and Tirau were constructed with timber subfloors before concrete slab construction became standard. Bathrooms in these homes are located above joists and bearing structures that are vulnerable to long-term moisture exposure. When a bathroom renovation was done without compliant waterproofing, as was common in pre-2000 renovations, moisture penetrates through grout lines and unprotected substrate into the subfloor structure below. The result is joist rot, bearer degradation, and structural instability. Our standard process is to expose and inspect the subfloor before any new floor covering is specified.
Water pressure variability in the South Waikato reticulation
Some properties in the South Waikato urban areas, particularly older sections of Tokoroa, experience water pressure variability in the reticulated supply network. This affects shower performance and can accelerate wear on older fittings and valves. When specifying shower mixers and fixtures for an older South Waikato home, we recommend tempering valves and pressure-equalising fittings as standard components. These are costed into the estimate, not added as surprises after the old plumbing is exposed.
Older bathroom renovations without compliant waterproofing
The AS/NZS 3740 standard for domestic wet-area waterproofing has been referenced in the New Zealand Building Code for some time, but compliance in older renovations has been inconsistent. If your bathroom was renovated before approximately 2005, there is a realistic chance the waterproofing behind the tiles does not meet current standards. When we strip out an existing bathroom, we treat the substrate as unverified until we have confirmed or re-applied the waterproofing membrane. We do not tile over previous work without inspection.
Why Choose Builders Waikato for a Bathroom or Kitchen Renovation
AS/NZS 3740 compliance, verified before tiling
We do not tile over an unverified substrate. The waterproofing membrane is inspected for coverage and continuity before any adhesive is applied. This step is the one most commonly skipped by cheaper operators. Skipping it is why bathroom renovations fail.
Subfloor inspection on every job
Older South Waikato homes frequently have timber subfloors that have been damaged by historical leaks, poor bathroom ventilation, or aging plumbing. We expose and inspect the subfloor before any new floor covering is specified.
Licensed trades only
All plumbing and electrical work is carried out by licensed practitioners under current registration. We do not use unlicensed labour on any restricted work. Every fixture, fitting, and service connection is compliant and documented.
Single point of contact
Brad manages the strip-out, the waterproofing, the trades, the tiling, the cabinetry, and the finishing. There is no handoff between a builder and a tiler who are both blaming each other when something is wrong. One person is accountable.
The Builders Waikato Handshake and Triple-Backed Guarantee: Bathrooms and Kitchens
Promise 1 - AS/NZS 3740 Waterproofing Warranty
All wet-area waterproofing is applied to AS/NZS 3740 and NZBC E3/AS1 standards. The waterproofing membrane is inspected and documented before any tiling proceeds. You have a record that the waterproofing was done correctly.
Promise 2 - 12-Month Post-Completion Walkthrough
Twelve months after handover, Brad personally returns to inspect and fix any settlement adjustments in doors, joinery, and trim resulting from normal timber movement. No call-out fee.
Promise 3 - No Unapproved Variations
Any subfloor rot, framing damage, or hidden moisture damage discovered during strip-out is documented with photographs and presented as a written variation before remediation work proceeds.
How We Deliver a Bathroom or Kitchen Renovation: Step by Step
Scoping Consultation
We review the existing layout, discuss scope of works, and confirm fixture and finish selections. We identify whether the project involves service moves requiring consent.
Strip-Out and Assessment
Careful removal of existing fittings, tiles, linings, and cabinetry. This is the diagnostic stage: we confirm subfloor condition, framing moisture, and waterproofing failures.
Subfloor & Framing Assessment
We inspect the exposed structure for rot, mould, moisture damage, and levelling requirements. Any damage found is documented and presented as a written variation.
Tiling and Cabinetry
Wall and floor tiling in the confirmed layout. Cabinetry installation and bench or vanity fit-out, ensuring precise alignment and finish.
AS/NZS 3740 Waterproofing
Concrete surfaces or floor sheets are waterproofed using compliant membranes. Substrate flatness and slope are checked to ensure proper drainage.
Framing Repairs & Preparation
Damaged framing or subfloor material is replaced. The substrate is prepared to the flatness and cleanliness requirements of AS/NZS 3740 before waterproofing.
Framing Repairs & Preparation
Damaged framing or subfloor material is replaced. The substrate is prepared to the flatness and cleanliness requirements of AS/NZS 3740 before waterproofing.
AS/NZS 3740 Waterproofing
Concrete surfaces or floor sheets are waterproofed using compliant membranes. Substrate flatness and slope are checked to ensure proper drainage.
Tiling and Cabinetry
Wall and floor tiling in the confirmed layout. Cabinetry installation and bench or vanity fit-out, ensuring precise alignment and finish.
Licensed Trade Fit-Out
A licensed plumber installs water supply and drainage connections. Licensed electrician installs lighting, extractor fan, and heated towel rails.
Final Inspection & Handover
Final quality check of all fixtures, fittings, and trade work. Warranty documentation provided, including the AS/NZS 3740 waterproofing compliance record.
FAQs: Bathroom and Kitchen Renovations
Other Services We Offer
Invest in High-Use Rooms Built to Last by South Waikato's Best Trades
A bathroom or kitchen renovation done correctly requires more than good tiles and a new vanity. It requires a builder who will inspect what is behind your existing walls before anything new goes in, who will apply waterproofing that meets the AS/NZS 3740 standard, and who will use licensed trades for every restricted element.
If you have seen the results of a renovation done on price alone, you already know why specification matters. Book a scoping session, and we will tell you exactly what your project will take.
