External Granite Surfaces in Cold WeatherRebecca Hinshelwood
Granite is an extremely popular material to use in external domestic spaces. Its natural durability makes it able to withstand the extremes of British weather through both summer and winter. Over the winter months, though, you may wonder will granite crack in cold weather? Of course, the extremes of the British Winter are variable. Some years are relatively mild, while others experience sustained periods of sub-zero temperatures.
Unlike more porous stones such as marble and limestone, granite is a functional choice for external surfaces, such as outside kitchens, BBQ areas or worktops. However, to alleviate the worry that the cold weather may cause your granite to crack, you can take preventative measures. So, what can you do to ensure your external granite emerges from the winter as beautiful as it was in the autumn?
What Causes Cracking?
Firstly, it helps to understand how granite may crack due to cold weather. When a material is porous and unsealed, it absorbs some level of moisture from the weather and atmosphere. This water then freezes and expands, thaws, and the process is repeated. This sustained pressure is what can eventually result in cracks to the stone.
Clearly, the key way to protect your granite surfaces through periods of cold weather is to ensure that the seal of the stone is intact. Check this by pouring a small pool of water on the granite surface. Leave for 30 minutes, and if the granite does not darken, your seal is going strong. If there is visible darkening to the stone, this means that moisture has been absorbed into the stone and the surface should be resealed.
Keep watch on your external granite over the Winter months and clear detritus from the surface. If leaves and moss are left piled up on your granite all winter long, the decaying mulch will require effort to shift. Similarly, clear any snow from the surface to minimise the direct contact of the stone in thawing and freezing of liquid. None of this will cause your granite to crack in cold weather. However, over time it can weaken the seal which will ultimately affect your stone.
As a preventative measure, then, it is wise to cover your granite for the course of winter. This will prevent the direct contact of moisture and mulch. It may, however, be tricky to source a large enough cover which will hold fast during windy weather. So it may be that clearing is more feasible than covering. If you have granite paving slabs and want to avoid icy slips, choose salt rather than grit. Grit provides texture on the surface but can scratch the stone, where salt prevents the ice from forming.
General Garden Maintenance
Watch out for general garden neglect affecting your granite surface. Overflowing gutters which continually drip on the surface can leave stains which will need a good clean come spring. For granite paving, weeds and moss which continue to grow over a mild winter can really take hold and are better dealt with continuously.
Good Ongoing Habits
The seal of your granite will be more durable if it is not damaged by harsh chemicals over the year. When your worktop is in more regular use over spring and summer, avoid abrasive cleaners. Warm water and dish soap is sufficient to clean your granite while it is in regular use. These habits will subsequently ensure that the surface seal is not damaged come winter.
Granite is a fantastic stone for external use. It is hardy, easy to care for and looks fantastic. It is extremely unlikely that your granite will crack in cold weather. When the seal is maintained, the stone will withstand the harshest of winters. Simply avoid long term neglect, and manage any maintenance in small but regular tasks. For some great ideas on how to use granite in outside spaces, just get in touch.