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Registered social landlords are responsible for nearly one-and-a-half million homes, and all of them should meet the government鈥檚 decent homes standard by 2010. This means that bathrooms are being closely scrutinised, as improvements to sanitaryware could be a cost-effective way of meeting the standard. One of the criteria for judging a decent home is that it should contain components that are in a 鈥渞easonable state of repair鈥�. Asset managers have to choose between the intermittent minor repairs of components and wholesale replacement. To do this they need life-cycle cost assessments to determine which is the best value option in the short and long term. Baths are looked at in most detail here as they are expensive and offer a range of options that affect lifetime costs.

What type of bath?

In practice a standard 1700 脳 700 mm rectangular bath is specified for social housing despite many other sizes being available. These may be made from cast-iron, steel or acrylic, and each has a different life-cycle outcome. Key properties affecting durability include the thickness of the bath shell, its rigidity, and its stain and scratch resistance. The thickness of the finished surface is particularly important in the case of acrylic.

The following gives an indication of the options available and performance issues.

Cast-iron

BS 1189 states that the porcelain enamel finish should be even and between 1 mm and 1.5 mm thick. It must meet minimum standards for resistance to abrasion, alkalis, acids and hot water 鈥� but using it to develop photographs is not recommended. From a life-cycle point of view, the additional costs of handling and installing a heavy cast-iron bath are balanced by its longevity and its robustness to impact and chemicals.

Vitreous enamelled steel

These baths offer a good compromise between heavy cast-iron and light acrylic while retaining an enamelled surface finish.

BS 1390 has two classifications of minimum steel thickness, 1.6 mm or 2.2 mm, although in practice a range of thicknesses up to 3.5 mm are available, at which point steel begins to compete with the robustness of cast-iron.

BS 1189 has minimum standards for resistance to abrasion, alkalis, acids, hot water and impact. The 2.2 mm thick steel meets a more demanding impact test so should have a better life-cycle performance.

Minimum deflection distances should be considered for the junction of the bath with the wall; 1.6 mm steel baths will deflect more and therefore are likely to need more frequent sealant replacement, resulting in higher life-cycle costs. Some steel baths鈥� support systems are not integral to the bath thus adding to capital costs.

Acrylic

All acrylic baths should meet the performance requirements of BS EN 198 for impact resistance, minimum deflection, temperature change and domestic chemical and stain resistance. Specific forms of acrylic baths are covered by separate standards. Cast acrylic baths must meet BS EN 236 minimum standards of resistance to ultraviolet light, hot water, chemicals and stains and be at least 2.7 mm thick.

BS EN 13559 covers baths made from impact modified coextruded ABS/acrylic sheets.

Acrylic baths are very susceptible to deflection and need a support system.

Maintain, repair or replace?

Baths are usually replaced for performance, accessibility or hygiene reasons. High frequency low-level causes of deterioration can be dealt with by frequent maintenance and intermittent repairs; the alternative is full replacement often at higher cost.

Worn surface layers, chipped surfaces, stains, scratches or surface scarring may result in health and safety risks and require replacement. Alternatives include specialist repairs which restore and replace enamelled surfaces in situ. These are generally more cost-effective than component replacement.