Mixing Mortar Tips - Mix Like a Pro

Learn when the mortar mix has obtained the desired consistency

Construction site: Adding water to mortar mix
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How to Mix Mortar?

Mortar mix is really an important building component that must be combined thoroughly. Mortar is the bonding material between bricks and stones and many other materials, made from sand, water and cement in varying mixtures and amounts. Mortar could be mixed by following these steps, just like the pros do.

Mixing Mortar Procedure

The following steps must be carefully followed to obtain the right mortar consistency:

  • Use a dry bucket to measure out the materials
  • Is always a good idea to pre-wet mortar containers before filling with fresh mortar.
  • Prepare a flat solid surface where mortar could be mixed. A good solid surface is recommended to reduce water being absorbed by the mortar mix.
  • Add 3 parts sand and 1 part masonry cement. If the wall is going to be exposed to lots of wind and rain you'll need the mix to be stronger, so use 1 part cement to 1/2 part lime and 4 parts sand.
  • Add two gallons of water on top of the mixture or inside the wheel borrow.
  • If you are mixing mortar manually, be sure to fold the mortar mix, from the bottom into the water. Keep mixing until the water is mixed.
  • Once that the water has been mixed, add another gallon of water and keep mixing.
  • Keep adding water until the mortar attains a smooth consistency.
  • You'll know that your mortar is ready when it's wet enough to slip easily off the shovel, but hold its shape if you make a hollow in the mix.

    Mixing Mortar Tips

    Below are some tips that will help you decide when to stop mixing mortar.

    • Your mortar has attained the correct viscosity when you can make a few ledges in the mortar mix and ledges stand up. Proper mixing will provide you with these simple results.
    •  If the mortar does begin to dry while applying, add more water.
    • You can add chemical plasticizers or masonry cement to improve the workability of the mixture.
    • Use good grade sand on your mortar mix. The sand should be free of clayey material, otherwise ,it will create a paste that could expand and contract as the water dries up. Try using fine sand for better results.
    • Cover the sand before using it. Sand absorbs water and it could change your mortar mix water requirements.
    • Using spec mix will avoid the sand being incorporated into the mix.
    • Every type of mortar mix contains different quantities of material. Be sure of the type of mortar mix needed.
    • Waterproofing agent is added to mortar for brick fences to prevent damp.
    • If you want to change the appearance of the mortar mix, add the dye before mixing the mortar.
    • Mixing mortar is based on consistency. Try to use the same materials and use the exact amount of material batch after batch. You can use a pail bucket to make sure you are using the same amount of material for subsequent batches. 
    • Mix mortar for not less than three minutes and not more than five minutes after the last materials have been introduced into the mixer.
    • When hand mixing, be sure to add all components before adding the water.
    •  It is best to use fresh cement (unopened bags) when mixing mortar. Cement bags that are opened, tend to absorb environmental humidity, thus changing the water percentage of the mortar mix.
    • Portland cement is recommended for mixing mortar.
    • Mortar is good for one and a half hour. Once that time has passed, discard mortar because it starts to lose some of its characteristics.
    • For almost 1,000 bricks make sure to use about 120 pounds of mix, and this will depend on how thick the joints are.
    • Weather might affect how mortar reacts and how manageable can be, so plan accordingly.
    • When working with mortar mixes, always wear eye protection and waterproof gloves.

    Mortar Mix Problems

    If you follow the recommended tips above, you should be fine, however, there are other issues that might affect your mortar mix and that are due to labor and materials. It is important to understand that once the mix starts to set, it cannot be re-mixed because it will affect the mix strength. Another issue is when more water is added to the mix, affecting the chemical composition of the mortar, reducing its strength and causing other issues later on.

    Lastly, adding the wrong admixture, such as dishwashing soap, will affect the bonding and strength capabilities of the mortar mix, as many of the pre-packed mortar have already admixtures that are activated once they are mixed.