Frequently Asked Questions
1. What colour grout should I use for my stone and/or tile?
Grout colour is very important as it can make such a difference to the overall look of the floor or wall. Although very much a personal choice, we would always recommend choosing a colour that blends with the stone or tile so that you are focusing on the tiles, not the grout joints. However, dependent on the tile you use, there are grout colours available to make the area more of a feature.
2. What does the slip rating of a stone/tile mean?
Most tiles are assigned a slip rating that will guide you as to which tiles are suitable for your project. For example, a high-slip resistant tile is suitable for a wet environment or external environment where the risk of slipping is greater. There are two different ways slip testing is done, with some materials having a PTV rating and some an R rating.
3. What are PTV / R ratings?
PTV stands for pendulum test value, which essentially measures how slippery a floor surface is when a foot comes in contact with it. PTV also calculates slip-resistance, and is measured with a pendulum that mimics a shoe on a surface. The results will determine the PTV or R rating and thus the suitability of the tile, for example:
PTV 11 - 18 (R9) - low friction. Suitable for dry internal domestic floors such as kitchens, dining areas and hallways.
PTV 18 - 34 (R10) - medium friction. Suitable for internal domestic floors subject to occasional wetting, such as bathrooms.
PTV 34 - 51 (R11) - high friction. Suitable for external areas such as patios, walkways, dressing rooms and pool surrounds.
4. How does a pendulum test work? (PTV rating)
Two types of rubber are used to measure the resistance of both barefoot and footwear. The slides make contact with the tile in the same manner as a human heel would at the point that slips occur. After striking the test surface, the foot swings and a measurement is taken to see how the friction of the surface reduces the energy of the foot. The test is conducted in both dry and wet conditions. A tile with a high slip resistance has a lower probability of a slip.
5. How does a ramp test work? (R rating)
Firstly, a ramp is covered with the flooring material that is to be tested. The ramp angle then increases in degrees until the tester, who is either barefoot or wearing a predetermined shoe type, slips. The test is then repeated on dry floors, wet flooring and contaminated floor surfaces. The results of the tests performed are averaged, and the floor material is given an R rating.
6. How should I cut my tiles?
Tiles should always be installed by a dedicated professional who is used to dealing with these products due to different materials needing different care, tools to cut, and installation. Natural stone and tiles can be cut using a diamond blade – ideally a water-cooled machine. Some porcelain, glass and ceramic tiles can be cut with a scribe and break type cutter. Tiles which are extremely thin will require various specialist tools due to having less surface tension. These tools include glass cutters and manual tile cutters, along with a tile cutter ruler. A specialist frame used alongside a hand-held angle grinder may also be required.
7. Can the driver take my goods into the property and help unpack?
No, unfortunately not. The delivery service we offer is a kerbside delivery via a tail lift courier. Once unloaded, the goods are the responsibility of the site team. The delivery driver is not insured to help handle the goods, move the goods into the property or remove packing, therefore it is essential that someone is present to receive the order.
10. Is Natural Stone Paving Frost Proof?
Frost Resistance is an industry term used to describe the inherent strength of a natural stone to withstand freeze-thaw weathering. However, it is important to understand that there is no accepted basis for passing or failing a frost test under the BS standards; rather frost resistances tests merely provide comparison to other materials. These tests are highly subjective however, and although we regularly retest materials within our range for frost resistance, it is important to remember that Natural Stone is natural, and thus naturally imperfect. Natural Stones can experience enormous variance in frost resistance between different areas of the quarry, different production batches; which will influence the brittleness/softness and water absorption, both which are key indicators of material frost resistant strength. Frost Resistance is based on the BS standard regulated Frost Resistance Flexural Strength test, in which a sample piece of the material will pass through at least 56 cycles of being cooled to below freezing and then thawed. This is designed to simulate wintertime temperature changes. This temperature change causes the stone tiles to expand and contract, which can cause damage to softer/more porous materials. Often a material strength test is undertaken following this to determine if the material has been weakened, or alternatively a visual inspection after the cycles of testing will determine if there has been any damage to the material, and this is noted on a scale of one to five. We review these tests to determine whether the material is suitable for use in a UK climate based on our experience of natural stone paving. Of course, in some areas the temperature will annually drop below freeing more times than the stone has been tested for. This does not mean that the material will denature beyond this point, and many natural stones are suitable for many more cycles than this. However, as an industry standard, it is accepted that at least 56 cycles of testing is sufficient to uncover any material weaknesses. Another important consideration is that the freezing cycle of the test only freeze-tests the material when dry. Water adds considerably greater stress to the material when the temperature goes below freezing, as this expands inside any natural microscopic faults and fissures in the material and pushes these open, a process known as freeze-thaw weathering. Some finishes applied to external Natural Stones to give enhanced anti-slip properties can make the material more open grain, exaggerating and worsening the effects of this process.
11. Is Porcelain Paving Frost Proof?
Yes, Porcelain paving is frost-proof, non-porous and suitable for year-round outdoor use. Frost-proof means it won’t absorb water (because porcelain is vitrified and non-porous) and therefore won’t crack or degrade in freezing temperatures.