There is a lot of confusion when it comes to mixing any kind of stucco, but we will be discussing the base coat mix in this article. I will use a custom recipe that will work for most applications and include how to mix in a bucket, wheel barrow and a mixer, which all require a little different techniques.
The mixing ratio of stucco is to use at least 3 cubic feet of plaster per bag of cement for the scratch coat and a maximum of 5 cubic feet per bag of cement for the brown coat.
Use the Scratch Coat Stucco formula and increase the Hydrated Lime and the Sand by 10%. This will make a weaker mix so as it dries, it will not crack the scratch coat. Moist cure for 48 hours and dry cure for 5 days before adding the finish coat (reduces the tendency to effloresce).
Re: Stucco home made formula Tom: Lumber yards and hardware stores carry a product called Mixquick (ther are also other brand names). It is already formulated for you. It comes in 90 pound sacks as I remember. They make several different mixes so be sure you get "stucco mix" and not something else like "mortar mix".
What Are the Directions for Making a Stucco Mix From Scratch? To make stucco for scratch coat, mix Portland cement, hydrated lime and sand. Mix the ingredients in a 5-gallon bucket or wheelbarrow with a hoe or other heavy pole, adding water until the slurry has the consistency of pudding. ... To adjust the formula to make the brown coat ...
Rapid Set Stucco Mix is a pre-mixed stucco material blended with Rapid Set Cement, high quality plaster sand, and high performance additives. Stucco Mix is used on exterior plastering applications where faster set times, higher strength, superior durability, minimal shrinkage, and reduced cracking are desired.
The stucco scratch coat mix is a simple recipe that really consists of sand, cement and water. There are other formulas that you can use but in its simplest form it is merely a 3 to 1 ratio of sand to cement.
If the mix becomes stiff, add more water until you get a more plastic, fluid mix. Excessive amounts of either hydrated lime or sand will weaken the mix, and while increasing the ratio of cement used will cause the finished stucco to have greater strength, it will also be susceptible to shrinkage and cracking.
Shop our selection of Stucco, Mortar, Cement & Concrete Mix in the Building Materials Department at The Home Depot.