Lime plaster and milk paint whitewash / by Lara Periut

I have a very creative friend in designer Brooke Phillips - thankfully - who dreams big and then asks me if I'd like to be a part of the actual finish work. Glutton for knowledge and experience as I am, I rarely say no! Currently my parents are living in my home while we renovate almost every square inch of their house. About a month ago when we went to order kitchen cabinets my father was amazed at how expensive the range hoods cost, yet that was something he really wanted to have instead of a microwave at eye level. Brooke merely mentioned that she loved the look of the plaster hoods as opposed to the painted wood, and since the house is under her creative direction I agreed to do the necessary research and make a plaster vent hood possible. What I did not expect was for my first attempt to be in a customers house instead of my parents - GASP! My nerves were frazzled not in fear that I wouldn't be able to accomplish said task, but the possibility that the products I chose weren't the best option possible for long term use. But hey, if the Romans could use slaked lime plaster on the wonder that is the Pantheon and it's still around to be admired, how wrong could I be to use it on a couple vent hoods?!

There is shockingly little information online about plaster vent hoods (as opposed to the plethora of images of such on Pinterest) and how to go about building and finishing them, so I decided to document my process for anyone else who may have the same desire. This blog site only allows me to add a few images, so a full viewing will be on my Facebook page, please check it out! I apologize if I end up wordy, it is only my intention to cover as many aspects of my experience as I possibly can, and believe you me, I felt like I was floundering there for a bit!

YouTube was the easiest place I could think to begin understanding the application of plaster. My only problem was that where there are several DIY vent hood builders allowing viewers to experience their work, there was only one single vent hood with a plaster application from a design company NeilWWilliamsStudios. His vent hood was pre-existing and needed to be stripped down to the substrate and built back with a more elegant look in mind. Unlike my vent hood, his was outdoors which needed special preparation that mine did not. I did note and keep in mind the process he used for filling all voids, sanding edges and generally making sure the substrate was as smooth as the finish coat needed to be.

So then the only question was how to make lime putty, and where in the world should I go to purchase it?! I first looked into art supplies: artists have used lime plaster and lime wash for centuries and there are several still in existence to this day. Considering that particular putty was not as descriptive to a novice as I needed and did not have the finish options I was looking for, I moved on to the general suppliers. I ended up at Benjamin Moore, they have always been helpful when I have projects and I am trying to understand the actions and reactions of products...only this time the fella was anything but helpful. He laughed at me when I asked about Venetian Plaster. It seems that both Sherwin Williams and Benjamin Moore stopped carrying their ready-made product once the mad craze for faux finishes died down. He informed me (with his nose in the air) that it was a devil to get the colors to mix. Lowe's, however, does still carry a ready-mixed Venetian Plaster for about $50/gallon only here's the rub: they only allow you to purchase it in about 7 colors and if you're wanting white (like I was) they absolutely will not let you buy it that way. Believe me, I ragged the guy for about 5 minutes just to see if he'd relent...he didn't. As much as I dislike ordering online, it looked like that was the only way availible.  

At first I was made aware of the difference between European and American products. I can understand and appreciate the superior knowledge Europeans have gained over hundreds of years of manipulating many mediums, but I didn't want shipping to knock me out of the running. I did, however, glean some amazing background information on Roman specifications, how Lime Plaster works on a chemical level and was enthralled by everything I discovered. I will never be the Chemical Engineer my father is, but one tiny gene must have passed my way in relation to understanding how natural pigments, sizing, etc. combine for artistic use. It was on one of these sites that I began to understand that the Romans preferred a three year slaked lime putty for longevity: when combined with water, the lime and marble dust begin to create a crystal chain (around the second year I believe) that produces a stronger bond in the finished product. Traditionally hair can also be used for strength, sold in perfect length bundles that I didn't feel that it would add to my project. After tucking this new knowledge under my belt, when I looked back to the product page I realized that all the two and three year slaked lime was completely SOLD OUT.

Not one to be easily daunted, I began to search for information on three year putty and landed on a blog that was extremely helpful to me.  Where I didn't need to use a few precautions Alex took to complete his plaster repair, I loved how well he documented his process and descriptions of his American made premixed plaster of choice: Master of Plaster. He too was a novice and the finish work was very close to what I was looking for, just a few more questions needed to be addressed and I would be out of the woods! 

I stumbled around the website and found a spec page for Master of Plaster's Venetian line which contains marble dust from France. It was more expensive than what they call 'veneer', but with the marble dust it would create the crystal chain I was looking for.  I also made a phone call to the rep for Master of Plaster, what questions I couldn't answer from the spec page Lauren easily answered and was so very helpful! She walked me through the steps recommended for a vent hood application with plywood substrate (she preferred hardibacker, but this one was already complete), from the bonding agent, to which self adhesive fiberglass mesh they liked best and possible finishes she had seen used before with positive results.

Last, but not least, I needed to address how I should finish plaster that will be above a cook top with moisture and grease. My search led me to another site with Earth Pigments and natural finishes. I learned about Roman Beeswax Plaster Cream, how to apply it and also that one can mix pigment directly into the wax for a subtle addition of color. Being a girl who loves a little bit of bling, I picked up a 3.5 oz container of Silver Pearl mica and thought it was completely beautiful even in the container! 


This vent hood was about 42" wide and 54" tall. The customer requested a very textured finish and more matte than high gloss as Venetian Plaster can be. I began by filling voids, sanding edges, removing a temporary block of wood between the beam and the hood that absolutely did not want to cooperate, and dusted everything from top to bottom. I did tape off the edges, but it was unnecessary since a brick veneer was going to be applied on the entire wall at the end of the week. Next I applied a thin layer of Larsen Plaster-Weld Bonding Agent directly to the wood substrate, I only needed a quart size and didn't even use half of that. It is pink and did garner a lot of ribbing from other contractors working around the house, but I was happy to be able to track my progress and cover any places I might have missed otherwise. Once that layer is tacky you have up to 10 days to apply your finish - mine was the following afternoon when I rolled on and formed the self adhesive fiberglass mesh with a 3" overlap. I was initially worried about height differences where the mesh overlapped, but that turned out beautifully with the float coat. I began every step of this vent hood up in the top left because there was only about 3" between the hood top and the beam running across the ceiling = quite a tight fit! The second coat of plaster went on a lot thicker than the first and was very easy to smooth out, even though I was requested to leave a textured finish I knew that that could be done better with the finer grains of the top coat. The finish coat looks very much like well mixed sour cream and is applied in a thin layer. As it dried I spritzed water on the surface and smoothed out any obvious bumps, but at the very end I dipped a putty knife in the finish and ran it over the top quickly for a knock-down look. Once this was allowed to dry for 24 hours, I came back and began to burnish everything with a putty knife. It was simple to knock down the highest places, but again I was aiming for a matte finish so I didn't spend too much time on this. I did spend some time sculpting the edges just a little and touched everything up that was not to my liking. After dusting the surface, I mixed some of my Roman Beeswax 3:1 with the mica powder. We decided that it had just enough pearl to it to warm up the white and give it a subtle shimmer as well. With a damp cloth I began to alternately apply plain Beeswax and the mica mix until the surface wouldn't accept any more wax. Then I burnished it all off with a dry cloth to a slight sheen. Pictures don't do the texture or the shimmer justice, so I truly wish you all could see this vent hood in person. It was quite fun to do and I can't wait to get to try the process again in my parents house! 

This is a list of what I ordered to cover two vent hoods, my parents hood will be half the size of the one shown above:

* One 5 gallon bucket Master of Plaster Venetian base coat - covers 140 - 160 square feet

*One 1 gallon pail Venetian Finish Coat - covers 94 - 103 square feet (I did use about 2/3 of the finish coat on the large vent hood due to texture requirements)

* 36" x 75' roll of self adhesive wall and plaster repair fabric

* 3.5 oz Silver Pearl Mica powder (way more than I'll ever use I'm sure)

* Roman Beeswax Plaster Cream 1 quart

* Larsen Plaster-Weld Bonding Agent 1 quart (I might have used 1/4 of the container, maybe less)

* new bucket, trowel and two sizes of putty knives

Overall I spent about $433.00 on supplies including shipping. Not bad really when you split that between two work orders.  



I realize the title implies whitewashing brick veneer with milk paint, but I feel like I've written a lot already, so I will be kind and only allude to my next post. The veneer applied to the wall behind the vent hood I plastered turned out lovely, but a little too pink. I was asked to add a whitewash over everything to tone down that overbearing color and I can't wait to show you what that looks like!