Is Salt Safe for Ice on a Back Deck?
Intro
Many Canadians enjoy using their decks year-round, but snow and ice build-up can make this difficult in the harsher winter months. So, how do you remove snow and ice from a deck? Before you pull out the shovel and salt, it’s important to understand the different types of ice and snow removal methods available, and which are appropriate.
Some ice-melting products are not safe for use on decks and can discolour or damage the decking and metal fasteners. Tools like metal shovels should never be used on any deck as the probability of causing damage is very high. Continue reading to learn more about the best ice and snow removal methods for your deck! You’ll help extend the lifespan of your investment and can even benefit the environment!
How to Remove Snow From a Deck
To remove small amounts of snow, use a soft broom or leaf blower. This should prevent scratching your deck.
For heavier snow loads, a plastic shovel may be used but caution needs to be exercised.
Always shovel parallel to the direction the decking is laid, never perpendicularly. This will reduce chipping your deck boards while keeping light scratches that do appear, less visible by blending into the grain.
Never use a metal shovel on any kind of deck as this is sure to cause scratching and chipping.
Powered snow blowers should also never be used on decking.
How to Melt Ice on a Deck
Here’s an example of a commercial ice-melter with added colorant. Avoid products like this on your deck, as they can cause staining.
The first thing that comes to mind for many people when it comes to melting ice is Salt, also known as Sodium Chloride. We don’t recommend salt for ice melting on any home surface. Not only can salt cause damage to wood and composite decking, but it also isn’t considered an environmentally friendly option. Luckily today, there are many more kinds of ice-melting products commonly available to homeowners for purchase, each with its own unique properties.
Regardless of type, many ice-melting products contain added colourant and traction agents (grit). We suggest avoiding these products altogether as they can stain and scratch your decking.
Types of Ice Melters
There are many different kinds of Ice Melting agents, each with unique chemical composition and characteristics. For the purposes of this article, I will be classifying them into two main categories: Chloride based, and non-Chloride based.
Chloride Based Ice Melters
Chloride-based ice melters include a variety of commonly available products, including traditional rock salt. The four readily available chloride-based ice melters include Sodium Chloride (rock salt), Calcium Chloride, Magnesium Chloride, and Potassium Chloride.
These products all work in the same way, by lowering the freezing point of water. This also means that they lose efficacy as temperatures plunge. For traditional rock salt, approximately 80% efficacy is lost once temperatures drop below -10 Celsius.
The issue with chloride-based ice melters is two-fold. Firstly, they pull moisture from their surroundings, including the wood components of your deck. This added moisture draw will gradually reduce the lifespan and appearance of wood products over time, especially in the case of Cedar and Spruce. Over time as the wood dries out, it becomes more prone to splitting and cracking.
The second shortfall of chloride-containing ice melters is that they are corrosive, which can be especially detrimental to fasteners and other metal components found on your deck.
Chloride-based ice melters can also negatively impact the appearance of concrete and stone patios and walkways, harm gardens and other vegetation, and cause irritation to pets and other animals.
While some of these products may be considered ‘better’ than others, we generally recommend avoiding the use of ANY chloride-based ice melters on your wood or composite decking.
If chloride-based ice melters are your only option, and you must melt the ice on your deck, we suggest using only Calcium Chloride, with no added dyes or traction agents. Use only the minimum amount necessary and wash any residue away with water once temperatures allow.
Non-Chloride Based Ice Melters
Today, there are several alternative ice-melting products available that include no chloride at all. Some of these options include Urea, Calcium Magnesium Acetate, Sodium Acetate, and other proprietary blends.
Of these options, we like Calcium Magnesium Acetate for melting ice on a deck, whether it be wood, composite or PVC. CMA contains no chlorine and is not corrosive to metal and concrete – in fact, it’s not corrosive at all! It’s also safe for wood contact as it doesn’t possess the same moisture-wicking characteristics. CMA is also safe for vegetation and is non-toxic for pets!
Sand and Other Traction Compounds
In some areas, sand is applied to roadways and sidewalks in the winter as a traction agent. This is not to be confused with an ice melter. Sand and other traction agents sit on top of the ice to provide more grip. They do nothing to melt the ice itself and act as an abrasive that can and will scratch your decking. Never use sand or other traction compounds on your decking. Be sure to avoid any other ice-melters with added sand or traction agents as well.
Key Takeaways
Avoid the use of chloride-based de-icers on your deck if possible.
If you can’t find a suitable non-chloride-based de-icer, use Calcium Chloride sparingly.
Where available, use Calcium Magnesium Acetate for de-icing your deck.
Never use traction agents, or de-icers containing them on your deck.
Never use de-icers with added colourants and dyes on your deck.
Conclusion
Keeping your deck free of snow and ice reduces the risk of injury, and allows you to enjoy it year-round. Remove light dustings of snow with a soft bristle broom, or leaf blower. For heavier snow loads, use a plastic shovel pushing with the direction of the decking.
When it comes to de-icing a deck, avoid using any chloride-based melter. Try finding a non-chloride alternative such as CMA. Look for a label on the package that says, “safe for pets”, and “safe for concrete”. Never use a de-icer that has added traction agents or dyes on your deck. For any ice-melting product, we recommend testing it on a small area first, as some brands may contain extra additives, such as anti-clumping agents.