FREQUENTLY ASKED QUESTIONS
BELLSTONE'S MOST COMMONLY ASKED QUESTIONS & OUR RESPONSES
1. Will my floor have an uneven surface?
Some projects are suited to uneven surfaces whilst others require a smooth finish which is achieved by using stone that has been honed. Naturally split material is very popular for use in areas where a non-slip surface is required. It is especially popular on outside areas such as patios, steps, pool surrounds and driveway applications. There are processes that can be applied to the surface of the material to give it a more uniform and luxurious appearance such as honing.
2. What guarantee is there that the colour will be consistent?
Natural stone varies in colour due to the different hues of the natural particles that make-up the product. Unlike man-made products, no dyes or artificial coloring agents are applied to homogenize the products – a manufacturing process that often results in loss of character. It is the variation in natural stone that makes each project quite unique. The colour variation also allows previously laid areas to be seamlessly extended many years later without obvious colour change.
3. Will the surfaces wear out or chip?
Natural stone is tough and very durable so it is unlikely to wear out – one of the main reasons it is used in public areas. Some wearing is evident on the stairs of public buildings but it usually takes 100 years of heavy traffic to make an impression. Natural stone will withstand a lot more punishment from hard objects than man-made products.
4. Will the surface flake or break away?
Naturally cleaved stone products can be subject to flaking but this can be easily prevented with the correct preparation. Flakes should be removed with a trowel or scraper, as the tiles are being laid. If flaking should occur after laying, the surface may be stabilised by applying a recommended sealant. Surfaces will not flake if the tiles have been properly laid.
5. Will stone surfaces survive a fire?
Natural stone is impervious to fire and will lower the risk of fire damage in any building - it would be nice if it lowered your insurance premium as well - but it rarely does!
6. What products are the safest surfaces around pools?
The ability of a wet surface to provide a good safe, non-slip environment for traffic, especially children, around swimming pools is of critical importance. Natural stone products are ideally suited to swimming pool surrounds because of their coarse and slightly uneven surfaces. The texture and surface finish of the stone is the key to it's safety. Providing the surface is not polished the vast majority of stone surfaces are far safer when wet than the man-made article - especially for exuberant children who love playing around pools and who tend to run rather walk! Sandstone, quartzite, travertine and limestone all provide good non-slip surfaces around pools, as do slates with irregular finishes. Natural split, tumbled, antique and flamed surfaces are most popular and provide good "grippy" surfaces. The best guide to the potential slip resistance of a stone are the wet pendulum test results that are published on this website under the relevant material.
7. Are light colours better suited to outdoor areas?
Dark coloured objects absorb and retain heat more than light coloured objects. If the outdoor surface is exposed to light and is going to be walked on by people in "bare feet", light coloured sandstone, quartzite or limestone are more suitable than the darker coloured slates.
8. How well does stone resist salt attack from saltwater swimming pools?
Natural stone has a history of holding up well beside swimming pools but the resistance to salt attack depends on how close to the water the stone is fixed and how frequently it gets inundated. Pool aprons that remain relatively dry will suffer least but pool coping on modern pool designs will be far more vulnerable because of their extremely close contact with the water and inundation from frequent lapping and splashing. No stone is completely "salt safe" because all stone is porous and absorbs water but some types of stone perform much better than others. Granite and quartzite perform extremely well when used as pool coping - our Grey Gum and Sofala quartzites experienced only 0.05% weight loss when exposed to salt attack in laboratory conditions. The benchmark guide for resistance to salt attack around salt water pools is a test result for weight loss of less than 0.1%. Sandstone is quite variable in porosity and density so care needs to be taken in the selection of the stone. Our Willow (0.2% weight loss), Bellandra and Chandra (0.4% weight loss) sandstones have much better salt resistance than Coolum (5.8% weight loss) - the latter is not a product that should be used around pools. All known resistance to salt attack tests results are published on this website on each product page. Water soluble, penetrating, hydrophobic (water repellent) sealers are designed to form a barrier to prevent the entry of moisture into the stone but even the best sealants do not make the stone totally impermeable. Remember too, that penetrating sealants are designed to allow water vapour (i.e. water as a gas, not liquid) to move into and out of sealed surfaces and that any salt that penetrates the under-surface of the stone will remain trapped. Sealing with a penetrating sealer (though not always recommended) will help protect your most vulnerable areas but they will only perform well if properly applied. Coping needs to be sealed top and bottom at least 3 times before fixing. In general, the best protection will be achieved by applying as many coats of sealant up to the point where the stone is not capable of absorbing any more. If the sealant is performing well, water will bead on the stone surface (and coping edge & under-surface) - failure to do so indicates the stone should be re-sealed. Some salt water pool owners prefer to leave the stone around their pool unsealed choosing to hose down inundated areas after use. In theory, this may work well as the salt is soluble, however it would be almost impossible to remove all the salt and whenever salt crystallizes in any porous hard surface, even concrete – damage to it's structure is inevitable.
9. Can stone be used on bathroom floors?
Most natural stone products are very suitable for bathroom floors but should be sealed with a penetrating sealant before use. Naturally split surfaces are most popular because they provide better traction. If there is concern about how slippery the surface may become check the surface treatment (natural split surfaces are generally safest) and refer to wet pendulum slip resistance test results (V = very safe is the best category).
10. Can I use stone outside in frost areas?
Stone is a wonderful product that will provide durable, long lasting surfaces in most areas – both inside and outside. Frost tolerance will depend on how much moisture the stone absorbs and how severe the freezing is and how long the temperatures remain below zero. In most parts of Australia frosts are mild and they dissipate before mid-morning the next day. Temperatures of -10 degrees Celcius will do far more damage than mild frosts. Water trapped in the pores of stone when frozen expands then contracts when the temperatures rise above freezing point. This expansion and subsequent contraction over a period of time may weaken the structure of the stone and cause cracking. Stone laid under verandahs and porticos where it is protected from rain and frost is unlikely to experience any problem. Stone varies quite widely in both density and porosity and this affects its ability to absorb and retain moisture. As a general guide, stone products that are dense (high bulk specific gravity test results) and have low water absorption rates will perform the best under freeze/thaw conditions. Some sandstone e.g. Coolum (4.3% water absorption by weight), is not recommended for exposed outdoor areas that are subject to frequent wetting and frosts whereas Willow (2.2% water absorption by weight) would perform better. Our Grey Gum and Sofala quartzites (0.17%) should be unaffected by frost.
11. Is slate a good outdoor surface?
Slate is a wonderful floor product for both indoor and outdoor use. Slate has been used as stair treads and risers on civic buildings for hundreds of years because of its durability and low maintenance costs. Remember though that the darker coloured slates will absorb heat and will get hot if exposed to the sun. Slate surfaces under pergolas and verandahs look great, work well and are extremely durable.
12. Are stone floors cold to walk on?
Surfaces covered with natural stone are refreshingly cool in summer and sometimes cold in winter but they do hold their heat better than most man-made products.
13. Does under-floor heating work with natural stone surfaces
Under-floor heating though not very eco-friendly, is incredibly effective with properly laid natural stone surfaces as the heat from the underlying slab radiates out, heating the surface.
14. What's the difference between tiles and pavers?
Most people associate pavers with outdoor use. Pavers are regarded as products to be used over soft bases (substrates) such as rammed earth or roadbase sprinkled with sand. On these foundations the stone used needs to be strong to ensure against movement that might cause cracking. As a result, the thickness of the stone needs to be 30mm or more, depending on the traffic load. These days, outside areas are often concreted providing an incredibly strong and very stable substrate. As a result, a much thinner "tile" of 10 - 15mm might be quite adequate (depending on the flexural strength of the stone and the traffic load expected). Apart from the thickness of the stone and the cost (tiles are cheaper!) there is no difference between a tile and a paver!