Aggregates – also called plaster sand when used for stucco – give cement plaster the body to be able to work in three dimensions. When the aggregates are graded and proportioned correctly – and combined with portland cement/lime or masonry cement – the matrix cures into a hard and durable wall.

Properly graded and proportioned aggregates save you money because they provide the maximum yield for a stucco base coat.

The applicator has sand piles delivered to the jobsite along with pallets of cement – they can blend together in a mixer.

As soon as the scratch coat material is firm enough to support the weight of the brown coat layer. It must be applied before 24 hours or you will have to wait an additional 28 days.

Yes.

There are three general guidelines for every stucco system: First there are broad national specifications to consider: EIFS and conventional stucco applications are part of the International Building Code (IBC).

Next there are specialty codes (fire & energy) and ASTM standards that apply.

And finally one-coat stucco systems – like Amerimix 740 Fiber Base Coat – will have an IAPMO report as an application guideline. Amerimix’s IAPMO Report is #427.

Stucco is a highly versatile material, able to be used in many applications, regions and over several substrates.

However, there are specific temperature ranges for the application of portland/lime and masonry cement stucco base coats and finishes, with particularly high temperatures requiring specialized blends such as Amerimix AMX 750.

Yes, typically after 7 days for latex based paint, but contact the manufacturer of the paint for their recommendations.

No, lathe would be required for proper mechanical bond.

28 days.

Yes. You can use Sakrete Bonder & Fortifier with a 50/50 dilution of water to product.

Most stucco systems are exposed at one time or another to large volumes of water in the form of wind driven rains. Because of this any wall system must have a ‘strategy’ for protecting the structure from water damage. The two most common approaches are water barrier systems and water management systems:

The strategy behind water barrier systems is to never let any water inside the building assembly. In other words, when built right the water never penetrates past the outer surface of the wall. This is difficult but possible to do. However, once there is a failure it can easily become catastrophic because large volumes of water can be trapped for an extended time before someone knows it, resulting in rot, mold, and expensive repairs.

The predominant strategy used now are ‘water management’ systems. These systems make the assumption that water will eventually work its way past the outer surface of the wall – but when it does a system of flashings, weather barriers, and metal or plastic weep screeds will direct water back to the outside of the structure.

All portland cement, hard-coat systems – either one coat or three coat – are built based on the ‘water management’ strategy.

Stucco is not completely waterproof, but it can be made very water-resistant with proper installation and maintenance. Stucco is a porous material, so it can absorb water. However, when it is properly sealed, stucco can repel water and prevent it from penetrating into the underlying wall structure.