Complete Bath Installation Guide

Budget-Friendly Bath Installation Guide: Step-by-Step Process for a Durable and Professional Bathroom Renovation

Renovating a bathroom is one of the most rewarding home improvement projects. In this particular case, we replaced an outdated shower setup with a new, robust bath installation, tailored for a growing family. Our aim was durability, functionality, and soundproofing — all executed with careful attention to technical detail. The entire process spanned approximately 15 working days and involved a full structural overhaul of the bathroom, including new walls, doors, plumbing, and finishes.

Below is a detailed breakdown of each critical step in the process.

1. Full Bathroom Strip-Down and Preparation

We began by completely stripping out the old bathroom — this included the removal of old shower items, structural walls, tiles, flooring, plaster, fixtures, and etc. All walls and floors were taken back to the bare structure. The house had been fully replumbed just prior to this renovation (also house first floor walls been restructured completely to gain more room in bathroom and two bedrooms), ensuring we were working with brand-new, clean copper pipework for optimal longevity. During demolition, it was discovered that the original framing lacked the integrity for a new bath installation. We took the opportunity to rebuild the bathroom structure, creating straight and true stud walls and installing a new, properly sized door frame and door.

2. Moisture-Resistant Wall Installation and Sound Proofing

Before boarding, we added sound insulation within the stud cavities. This is a key step often overlooked — but essential in family homes. It greatly reduces the transmission of bathroom noise (running water, drainage, etc.) to adjacent rooms, adding to overall comfort and privacy. We then installed green moisture-resistant plasterboards. These boards are designed to handle humid conditions far better than standard plasterboard. All board joints and screw holes were taped and sealed in preparation for waterproofing.

3. Floor Reinforcement and Preparation

For the flooring substrate, we used cement boards, specifically chosen for their outstanding performance in wet environments like bathrooms. These boards are a premium, best-tested and industry-trusted surface for floor tiling, offering exceptional dimensional stability, compressive strength, and superior water resistance. When correctly installed — fully bedded and securely screwed into the subfloor — cement boards create an ultra-stable, non-flexing base that supports both the bath and tile layers without risk of movement or cracking over time. Compared to traditional materials such as plywood or chipboard, cement boards offer far greater long-term durability, especially in high-moisture and high-use areas. In this project, their use was particularly important because the bathroom is located adjacent to a staircase, an area prone to subtle vibrations and structural movement. Cement boards absorb and dampen these vibrations far better than timber substrates, significantly reducing the risk of cracked tiles or loose grout in the long term. This made them not only a logical choice, but a necessary one for ensuring the resilience and longevity of the finished floor.

4. Bath Selection and Frame Construction

The chosen bath was a 7.5mm thick square acrylic bath. Thickness matters — thinner baths (2–4mm) tend to flex, leading to sealant cracking and eventual leaks. A 6mm, 7mm or 8mm bath is significantly sturdier and retains heat better, making it ideal for regular family use. The square shape was a deliberate choice. Compared to curved or rounded baths, square baths offer more internal leg room, making them more comfortable and suitable for both adults and children. Although the bath came with standard brackets, we built a custom bath support frame.

This was done for two main reasons:

• To prevent any bath movement during use, which can compromise seal integrity.
• To allow precision fitting of the bath panel later in the project, creating a clean, professional finish.

5. Waterproofing and Tanking

Before fitting tiles or finishes, we applied a full tanking membrane and waterproofing kit (from Mapei brand), a trusted brand in the industry. This included a liquid membrane over the walls surrounding the bath and wet zones, as well as sealing tapes at all board joints, wall-floor connections, and around pipe penetrations. This step ensures that any water penetrating the tile surface cannot reach the structure, preventing long-term damage and mold growth.

6. Bath Installation: Key Techniques

With the structure and waterproofing complete, the bath was set into place on the custom frame and securely fixed. Critical detail: We filled the bath with water during the sealing process. This step ensures the bath is under full weight load, allowing the silicone sealant to flex correctly and prevent cracking once the bath is later used. Once cured, the silicone forms a watertight seal that won’t pull or separate when the bath is filled.

7. Ceiling and Final Finishes

For the ceiling, we opted for composite ceiling panels. These were chosen for their:

• Water resistance (ideal for high-moisture environments)
• Low maintenance (easy to clean, no painting required)
• Affordability, which made them suitable for a mid-range budget renovation

This choice also tied in with the overall goal of creating a low-maintenance but high-performance bathroom.

8. Purpose Behind Shower-to-Bath Conversion

A significant part of this bathroom remodeling was replacing a shower with a full-size bath. This decision was driven by the fact that the house will be occupied by a family with young children. Baths offer:

• Greater versatility for young families (children’s bathing, cleaning, etc.)
• Improved resale value in family-oriented housing markets
• More relaxation options for adults while retaining practicality

Bath Installation – FAQs

Why Choose Bathroom Builders ?

At Bathroom Builders, we pride ourselves on delivering exceptional craftsmanship and customer satisfaction. Our team of expert bathroom renovators is dedicated to bringing your vision to life, whether it’s a complete bathroom overhaul or a simple update. We handle everything from bathroom tiling to plumbing, electrical work, and waste management, ensuring a hassle-free renovation experience. Discover how our bathroom remodeling company can transform your space into something beautiful and functional. Get in touch with us today for a consultation and let us help make your bathroom renovation dreams a reality.

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