Tim owns a home over 100 years old and needs to insulate the exterior walls with dense-pack cellulose while maintaining the house's historic appearance. He sent in a picture of the stucco finish, asking for details about the finish type, how it’s made, and the tools required to replicate it.
Question from Tim:
I own a home that's over 100 years old & need to badly insulate the exterior walls (using blown-in dense pack cellulose) while maintaining the historic appearance of the house. I am trying to figure out what the stucco finish on it is called & how it is made & with what tools. I'm including a picture of that stucco finish with this inquiry. Any help from you would be much appreciated.

Answer:
Hey Tim, thanks for your awesome question and for including the photo of your stucco finish, it makes it so much easier for me!
Based on the image, the finish appears to be a two-coat process, although it’s difficult to say whether it was originally applied this way or if a new texture was added over an existing finish later. Here’s what I can tell you about the finish and how to replicate it:
Identifying the Finish
- Base Layer (First Coat): The first coat appears to be a smooth sand finish, likely created using a traditional sand-texture stucco. This provides a consistent and flat base.
- Top Layer (Second Coat): The second coat has a more unique, hand-applied texture. It seems like a troweled finish where the material was applied in small amounts, allowed to drip slightly, and then lightly troweled upward in short, inconsistent swipes.
The sand used in the second layer looks very fine, likely a 30-mesh or finer sand, which helps create the delicate texture you see.
Tools and Materials
To recreate this finish, you’ll need:
- Trowel: A standard stainless steel trowel for both applying and creating the texture.
- Stucco Mix: A custom finish material would work best using plastic cement, a fine sand, and a little extra lime to help the material hang on the wall. Ensure the second coat has a slightly wetter consistency for easier manipulation.
- Float or Sponge: A float or sponge is needed for the first base coat to achieve the sand finish look.
Application Technique
If I were replicating this texture myself, I would tackle it like this:
- Base Layer: Start by applying a sand finish as your base coat. Use a trowel to achieve a smooth and consistent surface, then use a float or sponge to achieve the sand finish look.
- Texture Coat: Make a custom texture coat material using plastic cement, fine sand, and by adding slightly more lime, so the mud hangs on the wall, which would help for those "globs" of material that cling on. Mix with slightly more water than usual to achieve a wetter material.
- Apply small amounts of this mix onto the wall in patches. Let some of the material naturally drip, and then use upward pressure with the trowel to create short, overlapping swipes. Each swipe should cover just an inch or two and leave some variation for a natural look.
- Work in small sections, blending the trowel swipes together to ensure there are no large gaps and use slightly different angles to match the existing finish’s orientation as closely as possible, but mostly horizontal angles.
Tips for Matching Historic Stucco
- Practice on a Sample Board: Before applying directly to your walls, practice the technique on a sample board to refine the texture and ensure it matches the existing finish.
- Color Matching: The finish will likely have to be painted afterward to match the color. I am not sure if your existing finish is painted or not, but a color match and texture match would be very difficult, even for a talented applicator with years of experience.
Tim, the finish you’re working with is a beautiful and unique texture that seems to be the result of a two-coat process. With the right materials, tools, and some practice, you should be able to replicate it or someone who has the skills to replicate custom stucco textures. Let me know if you have additional questions or need further guidance!