A Green Portland Cement Alternative, FAQ Friday with Randy Ruth

You might ask yourself… How is Natural Hydraulic Lime (NHL) a green building material? The simple answer would be that it releases about 80% less CO₂, pound for pound when compared to Ordinary Portland Cement (OPC) during the manufacturing process. But why is this so? Well that requires a bit of understanding on the manufacturing of the two very different products.

Both NHL and OPC are made from limestone, although not necessarily the same kinds of stone and are fired in a kiln. NHL is produced in Vertical shaft kilns, which is like a big chimney, with natural gas or clean coal at a low temperature. While OPC is burned in a rotary kiln fired at nearly 2,500 F. The amount fuel used to maintain such a high temperature is by far greater than the relatively low firing temperature of NHL.  Often hazardous waste is used as a fuel, which can emit toxins into the atmosphere. During either process CO₂ is driven off into the atmosphere. Even though NHL production drives off less CO₂, the benefits don’t stop there.

When the NHL is ready to be mixed as a mortar right out of the bag, it’s hungry. NHL wants the CO₂ that was pumped into the atmosphere back all for its self, in its natural process to turn back into a limestone. As different grades of NHL are produced their whiteness and density change. On a scale from lightest to heaviest and from whiteness to grayness, NHL 2 is Light and white while OPC in heavy and grey. Since mortar is mixed by volume in the field, less lime is used per pound to make up the same volume of mortar using OPC.

-LimeWorks.us (Linked-in : Blog : Facebook : Twitter)

Lime Paint Brush vs other paint brushes? FAQ Friday with Randy Ruth

Often when applying Lime Paint the surface texture may be rough, such as that of a brick, stone or stucco. A good brush for Lime Paint should be made of a high quality, durable natural bristle. What would be the most distinctive difference is the size. The wider thicker ferrule allows for more bristles and allows for a greater painting efficiency, due to its greater capacity to carry the thin paint.

 

Imported Lime Paint Brush

Generic Paint Brush

 

 

 

 

 

 

 

 

 

 

 

 

-LimeWorks.us (Linked-in : Blog : Facebook : Twitter)

Chalky Finish With Lime Paint, FAQ Friday with Randy Ruth

Q: I want to use Lime Paint as a finish of my basement walls but am worried about it chalking. What can I do to prevent or fix this?

A: When used as a finish over any sort of acceptable masonry Lime Paint can create a beautiful durable finish, when applied appropriately. Chalking of a Lime Paint can be reduced when it is applied in numerous very this coats as always recommended. Although it will not be eliminated, it will certainly help for the longevity of the coating. Now if chalking is of the upmost concern there is a simple solution. By applying one thin coat of PrimaSil, (potassium based “water glass”) almost all chalking is eliminated. The color of the finish may change slightly depending on the absorbency of the background and Lime Paint. Typically, this is so slight that it is inconsequential.

Total Repointing, FAQ Friday

Q: What is the correct method for total repointing?

A: Correct total repointing requires removing the joint to a depth of approximately 2-1/2 times its width and then using a compatible mortar in relation to the final p.s.i. and both the liquid and vapor transmission rate as that of the remaining joint and brick. High lime content pointing mortar is compatible with
the soft and absorptive nature of historic brick which rely on their “fired skin” to protect themselves and the building from rain intrusion. If high concentrations of Portland cement were in the repointing mortar instead of lime, when moisture in the brick were to expand and contract during freeze/thaw cycles, often the unyielding mortar forces the softer face of the brick to exfoliate thus leaving a vulnerable unburned “salmon” center of the brick exposed to the elements.

Damaged Bricks, The Quick Moving Culprit? FAQ Friday

Bricks can hollow back quite profusely in some cases. What are some of the causes?

Don’t forget vermin. Accelerated wetting and drying cycles near the bottom of the brick building cause an increase in the decay of the soft bricks. However, where there is water and calcium rich lime mortar there can be ants and bugs nesting in and behind the wythe. Masonry Bees are found in some parts of the country and will burrow. Sparrows and Starlings will take the calcium bits from lime mortar and like a cuttle bone use the grains for digestion. Some very deep holes in the brickwork are from wood peckers who sense the presence of the bugs and they hone in on certain areas in an attempt to get to them. Here’s one example that may have been caused by a combination of water and animals.

Staying Connected in the Digital Age, FAQ Friday

With the Holiday Season upon us and all the new gadgets bound to be found around the Christmas Tree soon I wanted focus today’s FAQ Friday on technology and how we’ve been getting better connected here at LimeWorks.us this year. Over the past six months we’ve released a barrage of updates and additions to our online presence. In August we completely redesigned our website giving it a more modern look and a new organized structure.

Our new website now has a live chat feature where you can ask questions and seek out advice from our team of skilled masons and lab technicians.

Our new online store is completely stocked with all of our products including our popular line of Ecologic® Mortar and Lime Paints. You can find all of our kits there as well including our graveyard kit and the Master Conservators Kit.

Our blog has grown rapidly and is a great resource to keep up with some very interesting projects going on with LimeWorks. Randy Ruth, our Lab Technician has been posting some great articles on proper application of lime including mortar joints, lime paints and even plastering. The FAQ section of our blog is a wonderful resource to answers to many common questions.

Facebook Twitter and Google+ are now part of our daily vocabulary and we’ve been working hard to post some great stories and photos throughout our social media network. If you haven’t “liked” us yet or “followed” us on Twitter you don’t even know what great stuff you’re missing out on!

      

Bringing it all together, we took the final step into the 21st century recently here at LimeWorks.us by upgrading our old-timer Motorola talki-phones to the newest Iphone 4s equipped with our newest friend Siri.

With the iphone we’ve been able to share photos and videos on-site, pushing them live to facebook, youtube and twitter adding a completely new way of spreading news on achievements for historic preservation!

But now we want YOU to start sharing with us all the great efforts going on across the country for historic preservation and new sustainable construction. Pull out your iphone, blackberry or android phone and capture your own photos and videos. Email and tweet them to us or post them on our facebook page and keep us in the loop on how you’re using Natural Hydraulic Lime to preserve our built heritage. We’ll then take the best stories and post them on our blog and spread them across the internet for everyone to see and effectively encouraging what’s best for our historic buildings.

Green Construction in Today’s Built Environment- FAQ Friday with Randy Ruth

When people talk about “green” construction, I often wonder what the environmental benefit of the construction is. Is it new construction? If so what is the environmental impact? I would hope that a perfectly good existing building wasn’t torn down to make way for supposed progress.

It is my belief that the greenest building is the one that is already standing and most likely played a role in a community’s development. It could be an old department store, manufacturing warehouse or barn. Sometimes plans call for only the façade of a building to be saved which helps keep the architectural integrity of a community intact. This can be a positive compromise because the more useful modernized building can be built and yet some historic fabric is retained to tell the story and retain the flavor of what the building was in its local context.

In the end, as long as something is retained for adaptive reuse, whether it is for aesthetics or the entire structure, there is a measure of success in reducing a “green” construction project’s carbon footprint.

In most instances, a building that has been saved from the wrecking ball is old. What does old really mean? Well that’s pretty subjective but I would like to think of old in the context of US building history as being pre 1930, or roughly 80 years and older. When an old building is going to be adaptively reused one way or another then appropriate materials should be used to fix what is broken with compatible repair materials. Using in-kind repairs will further promote the legacy and overall usefulness of a building for years to come while lowering its impact on the environment.

Old buildings are usually very strong and often made of brick and stone that has proven to stand the test of time. However it’s the mortar that binds those materials together and meant to be sacrificial. Mortar should fail first not irreplaceable historic masonry units. The embodied energy to replace a masonry unit is much greater than the mortar. Therefore, it is imperative that a suitable replacement mortar be used to mend what is failing and the mortar be weaker and slightly more permeable than the surrounding masonry units.

In the case of masonry mortar, lime is typically the binder in these old buildings and should be regarded as key to the dynamic that has allowed the building to be in service so long. Often the original mortar is still in place, proving its superiority and therefore should be replaced in-kind. The use of modern day Portland cement based mortars, which are stronger and denser when placed over the top of lime based mortars, are less sympathetic to the historic masonry and can trap moisture causing further damage to the historic fabric. The historic masonry units and adjacent historic elements can best be kept in conservation with the use of the right lime mortar. The correct Natural Hydraulic Lime (NHL) mortars when used where they are appropriate can become a compatible repair materials that is sympathetic  to the working dynamics of an historic masonry building. Secondly, NHL mortars remain reversible without damage to the building unlike the alternative which is the too over-used hard, brittle and dense Portland cement based mortars which are known to cause irreversible damage in conjunction with historic masonry fabric.

-LimeWorks.us (Linked-in : Blog : Facebook : Twitter)

Lime Paint and Plastering System for Interior Application, FAQ Friday

Building on last week’s FAQ Friday, the use of lime paints doesn’t have to stop with use on the exterior of a building. Lime paints are great for use on interior walls by themselves or used as a pre-hydrated and dispersed pigmenting agent that can be mixed with Ecologic^® Mortar, NHL or a combination of the two when formulating your own colored plasters.

There are many benefits of using lime paint on internal walls but there sometimes needs to be some preparation involved to make sure that the lime paint or plaster will adhere to the substrate. Often times I hear that someone will want a colored plaster finish on their interior walls but they do not know if lime paint will adhere. The simplest way to check is to spritz some water on the wall. If there is no absorption of the water, the wall is either too smooth or not porous enough. We need some suction. One way to achieve this is to apply a base coat of Takcoat™.

Takcoat™.  was discussed in detail in a previous FAQ Friday. So to keep it short I will just say that it is a VOC free, transitional lime and sand prepared plaster material that can be applied to smooth painted or unpainted surfaces. Once Takcoat™. is cured then adequate suction and mechanical key is provided for Lime Paint and lime plaster to adhere to the wall surface. There are ranges of different lime finishes that can be applied to the wall ranging from a rough open pore surface texture to an incredibly smooth polished Venetian or Tadelakt finishing style. The finish is dependent on the client’s wishes and the skill level of the craftsperson.

In my opinion, craft skill level is fundamentally dependent on the tools a craftsperson has at their disposal. One important tool to have when formulating different plasters is pigmentation. The lime paints we sell at LimeWorks.us come in a variety of colors that can be used as integral pigments mixed into plaster formulations or on their own as a decorating top coat. Having a good pigmentation methodology gives a craftsperson more options during the planning stages of a project. A good pigmentation methodology also makes reproduction of the mockups on to the entire application easier once a decision has been made on a certain color since the consistency of our products makes this a smooth process.

Lime paint comes as a dry powder consisting of a high calcium lime paint base and dispersed pigments if the paint is a colored one. Dilution of the lime paint with water to make a quart, gallon or 5-gallon unit will further breakdown the pigment and further slake the hi-cal lime. When a known volume of paint has been made it can be used in Ecologic^® Mortar formulations or gauged into lime plaster for color. Here are a few examples…

Sample 1- lime paint lp-347 over Takcoat™

Sample 2- 1/2 bag NHL 2, 4.3 gallons LP-347, 1.09 gallons water over Takcoat™

Sample 3- one bag Ecologic® Mortar Fine with 1gallon LP-347 over Takcoat™

Sample 4- one bag Ecologic® Mortar with 1quart LP-347 over Takcoat™

When a specific color is desired but not represented by our stock lime paint color options then we can provide custom colored blends for all sorts of various applications. Seen in the photos below Thuillier Plastering of New Hampshire used a custom Ecologic^® Mortar Fine that incorporated additional NHL 2 and pigments to achieve a Tadelakt finish. The authentic formulation was then polished with rubbing stones and the olive oil soap we sell, following an ancient Moroccan tradition.

So whether you know what style of plaster finish you want to achieve or you would rather let your imagination run wild and experiment, just contact us and we will be able to help you develop your plaster system to ensure a successful project.

-LimeWorks.us (Linked-in : Blog : Facebook : Twitter)

All About Lime Paint, FAQ Friday

Although they date back thousands of years, some of the best examples today of lime paint are those pictured in scenic postcards of gleaming white and pastel colored villages, so abundant throughout the Mediterranean. Many architects and designers currently seek a return to these methods and products of the past. Lime paint changes and evolves as it slowly ages, giving buildings an appealing, provincial look. Additional coats can be added as time goes on, enhancing the depth of colors. Modern paints often seal in humidity, which later leads to peeling and other exterior damage to a building’s surface. More like a stain than paint, lime paint is absorbed into the wall, penetrating the background. Once cured, the lime paint allows the surface to breathe, becoming a peel-free surface as it allows humidity to escape.

Examples:

Lime Paint base, (Natural), has no color added. It can be used to whitewash an old masonry building with only two coats and turn a dingy structure into a “museum-like” historic landmark. This is the Gambrel Roof House in Historic Fallsington, PA.

Before

After

A home in Lambertville, NJ originally had a shelter coat of lime wash put on the soft under-fired brick. #345 St. Astier Lime Paint was used to refresh the building, protect the brick and maintain good breathability for the coating so as not to trap moisture in the wall.

Before

After

A home in Stirling, Scotland which has had the facade restored using colored limewash over a lime/sand render. The home is located along the way up to Stirling Castle.

 

 

 

 

 

 

 

 

The Coastal Heritage Society Preservation Team members of Savannah Georgia whitewashed the retaining wall at the Roundhouse Railroad Museum using St. Astier lime paint.

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A home in Massachusetts originally had a harled finish coat of lime stucco. The St. Astier Lime Paint #429 was used to refresh the building’s exterior look while protecting the soft lime stucco with a “like to like” compatible coating that will wear down over time rather than flake and peel off. The work was accomplished by Florentine Masonry Restoration.

-LimeWorks.us (Linked-in : Blog : Facebook : Twitter)

Lime Mortar and Hardscaping, FAQ Friday with Randy Ruth

When it comes to hardscaping with masonry, I am all for mortarless construction. The beauty of a well built dry stacked stonewall or paver application creates a natural aesthetic on any property. Often times however, there is a need or desire for a more permanent structure requiring mortar. Traditional brick garden walls in a Flemish bond pattern are a particular favorite of mine. The truth is hardscaping options are endless with so many creative ideas for an architect or master mason. Variations in brick bond patterns can come up abruptly with changes in architectural style creating such visually stimulating surround that once immersed, one may find themselves in a peaceful wholesome setting. I find myself not feeling this way in locations recently constructed but in older, aged locations, where there is a bit more character. This character comes from the details in construction.

With mortar taking up about 20% of  the surface area on a wall, it is no surprise that mortar detail has a subtle yet powerful effect on the visual appearance of a masonry wall. In the construction of modern brick walls, Portland cement sticks tenaciously between the bricks, with characterless mortar joints. The two most prevalent types of mortar joints I see are concave and grapevine. While the concave mortar joint is meant to keep a watertight seal between the brick, it looks out of place. Rather it would be happier on the façade of a modern home, office building or utilitarian structure. The grapevine mortar joint style might be a romanticized take on old historic brick jointing that is often abused in modern construction but is not as aesthetically displeasing.

Despite my opinions on joint profiles, it’s the overall appearance that a modern Portland cement causes a hardscape wall to have. Unsightly control joints and modern joint profiles are a direct result of mortar used on a hardscaping project. The use of lime-based mortar can counteract such unsightly details and can be truer to the envious historic gardens of yesteryear in aesthetic quality.

Construction of hardscaped brick walls do not need to have control joints when lime is employed as the primary binder in lieu of Portland cement due to lime’s natural flexibility and free lime content which permits autogenous healing of micro-cracks. The use of lime in new construction is also “green”. The carbon footprint of using lime as a primary binder reduces co2 emissions by as much as 80% when compared to Portland cement. This reduction in emissions represents a greater step forward toward sustainability in our built environment. The breathability of lime mortar also promotes the idea of free flowing and natural earthen feelings associated with hardscaped locations. When our spaces work with moisture and process water rather than trying to trap it, a harmony is produced. This can help bring into sync the man built environment with the natural growing environment of an outdoor space.