How to Build Mortared Stone Walls

Mortared stone wall

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With a little planning and a lot of sweaters, building mortared stone walls can be a fun winter hardscaping project.

Building a mortared stone wall is more challenging in the winter. Not only will you be lifting heavy stones and mixing mortar, you'll be doing it in less than ideal conditions. It won't be easy. But if you enjoy a challenge then follow these steps and you can build such a structure successfully even in winter.

Plan Ahead

This is a good idea no matter what time of year you're building a mortared stone retaining wall, but it's especially important in the winter. Depending on where you live, the cold and possibly the snow could make life difficult for you. So, it's particularly important to plan ahead.

  • Layout: Do the layout for your wall before winter arrives. It will be easier to do the planning before the ground freezes.
  • Pour the concrete footings before the ground freezes: We'll talk more about pouring concrete footings for mortared stone walls later.
  • Materials: Figure out what materials you need, get them on-site and get them covered with tarps. It's easier to do this before cold weather sets in.
  • Clean-up: You're bound to spill some mortar on your stones in places where it doesn't belong. The sooner you can remove this mortar, the easier it will come off. Plan on having muriatic acid on hand to remove those spills immediately.
  • Make a plan to keep everything warm: We'll talk more about this, but this is the most important part of building a mortared stone wall in winter. Mortar, like all concrete products, must be kept above 40 degrees to cure properly. The tips in the following pages will help you accomplish this.

Pouring Concrete Footings in Winter

If at all possible, pour concrete footings in the fall before the ground freezes. If the ground doesn't freeze where you live then, naturally, this isn't as big of an issue. If you don't get the footing poured before the weather turns cold, it's ok. You'll have to keep the concrete warm. Concrete, like all cement products including mortar and thinset, needs to be kept above 40 degrees to cure properly.

You can keep a concrete footing warm by covering it with plastic as soon as it's poured, and then cover it with hay. Hay makes great insulation and is fairly inexpensive. Make sure you use enough hay to cover the whole footing. Keep the footing covered for at least ten days. When you start building the wall, don't remove the hay and plastic until you have to. If you're building a large stone wall, you can expose the part of the footing you're working on and keep the rest covered.

Set up a Tent to Work Outside

Setting up a tent is a great way not only to keep yourself warm when working outside in winter but to keep your materials warm, too. This tent is actually a carport. It makes a perfect tent for building a mortared stone wall in winter. It's lightweight and easy to move, yet durable enough to withstand the elements in winter. And the clear plastic not only lets the sunlight in, which helps keep things warm; the natural light creates a pleasant work environment.

You can make a tent yourself out of wood or plastic piping and cover it with plastic or tarps.

  • Make sure your tent is big enough to keep your materials covered and gives you enough room to work.
  • Don't make your tent too big. It will be difficult to heat.
  • Let it breathe. You'll be running heaters inside your tent and you want the fumes to have a way out.

Using a Heater When Working With Mortar

If it's below 40 degrees (inside the tent, in this case) when you are working with mortar, you need to run a space heater. Space heaters usually run on kerosene or diesel fuel. They can be purchased or rented from many home improvement stores.

Using a heater is very important when building a mortared stone wall in winter. It will help keep you warm while you work. It will help keep the mortar warm, enabling it to cure properly. It will help warm the stones, which will aid in keeping the mortar warm.

Make sure the tent has plenty of ventilation. You don't want to get sick from the fumes emitted by the heater while working.

Don't leave the heater running while you're not in the tent. You don't want to burn your tent down.

Keep Mortar Warm While Curing With Insulation

You'll need to keep the wall covered and warm. You can use house insulation, hay, sleeping bags, anything to keep the mortar above 40 degrees. You can buy special heating blankets that will heat the wall all night, ensuring that mortar is kept warm while curing. These can be pricey but may be worth the money if you are undertaking a large project.

Anytime your heater is not running, throw something warm over the wall. At the end of the day, put the wall to bed. Cover it with as much insulation as you can, then cover it with tarps. Don't uncover it the next day until you're ready to run the heater.

It takes extra work to build a mortared stone wall in winter, but you have to make sure you keep the mortar above 40 degrees while curing. I know, I know, I keep saying that, but it's very important. If the mortar gets cold your wall will fail. Make sure you have plenty of insulation.

Stone Wall Construction

There's no doubt about it, stone wall construction in winter is a challenge. And, like most challenges, it's very rewarding when completed. If you remember my two most important tips for building a mortared stone wall in winter, you'll be fine: plan ahead and keep the mortar warm.

Working in the cold can be fun. It's a great way to stay active in the winter. And when spring arrives, you'll be ahead of the game. So get out there this winter and build a stone wall.