LimeWorks.us is a big part of helping to restore a prominent landmark in New York City, St. Patrick’s Cathedral. The Cathedral was completed in 1878. Then in 1888 spires were added. The picture below is taken from near the top of one of one of the spires.
The Cathedral is undergoing an extensive restoration project.
Workers are in the process of fully restoring the St. Patrick’s Cathedral. This work includes cleaning and repointing all exterior stonework and repairing the stained glass windows. LimeWorks.us is supplying all of the lime mortar for the full repointing campaign using our Ecologic Mortar (SCG) F; that is made of St Astier NHL and sand. This work is necessary to ensure that this beautiful New York City landmark endures for many future generations!
Thanks to the gracious invite by Deerpath Construction, the contractor doing the work, who extended to those of our staff in attendance at APT NYC, we received a special tour up on the scaffolding. It was an awesome view and wonderful to see our Ecologic™ Mortar based made with St. Astier NHL being used to restore this famous and very important building of the NY skyline.
Straw bale construction is the best of both worlds, it is a green and sustainable way of building and can be affordable with low maintenance and amazing insulation that will help keep energy prices low.
Natural Hydraulic Lime is crucial for success when building with straw bales. Two factors that make Natural Hydraulic Lime so great include its breathability and its ability to self heal and repair cracks through “autogeneous healing.”
Recently a team of volunteers spent 7 days working with Andrew Morrison of strawbale.com to construct a 10,000 sq. ft. straw bale eco center.
The University of Virginia is the only US university with a World Heritage designation, it’s conservation is of the utmost importance and is currently undergoing the largest restoration campaign in decades. Matt Wolf and his team from Centennial Preservation are currently working on the repointing and window repairs for the Rotunda at Thomas Jefferson’s Academical Village.
The Chemical Heritage Foundation released an episode of their award winning podcast Distillations. In this episode, Randy Ruth, formerly of LimeWorks.us, discusses the chemistry behind lime mortar, historic masonry buildings and the ongoing efforts to preserve one of the finest works of notable Philadelphia architect, Frank Furness. The 19th Street Baptist Church located in South Philadelphia has been in a state of disrepair for decades. This episode sheds light on the chemistry behind its construction and the ongoing preparation to save it.
Randy Ruth, at the time, was the lab tech at LimeWorks.us. He bridged the gap between architects, conservators and masonry practitioners on what types of building materials to use in reconstruction and restoration of masonry projects throughout the country.
“Randy and his colleagues at LimeWorks.us based in Quakertown, Pennsylvania were brought in to try and save the 19th Street Baptist Church
We took a look at at the types of mortars that were there and by knowing that the building was built in 1874 we could gauge what those original binders were without even necessarily doing an analysis. Architects, engineers and of course masons would use the local available materials which were at the 19th Street Baptist Church primarily lime based binders.
Lime is a very general term for inorganic materials that contain calcium and it’s been use in concrete and building materials since the Roman Empire. It’s derived from limestone and other rocks that are primarily made of calcium carbonate.
Basically lime is that calcium carbonate stone and it’s put into a kiln with fuel. These kilns would then be fired up to 900 degrees Celsius or slightly above and then the resulting product is a limestone that loses about a third of its weight because it’s driving off carbon dioxide so that calcium carbonate is now becoming calcium oxide.
This is all part of what’s called the Lime Cycle. Calcium carbonate is heated to produce calcium oxide and then it’s combined with water to form calcium hydroxide. Different amounts of water is added to form different consistencies.
That process is called slaking, if just a small amount of water is added it’s going to turn into a powder. If a little bit more water is added it’s still calcium hydroxide but it’s in the form of a putty.
Once the lime is in this putty form it’s spread over bricks and stones and hardens into a solid bond.
That limestone then stays malleable and flexible in a wall system in comparison to more modern materials.
Modern materials like cement. Portland cement is the most common type of cement used around the world. It’s made of primarily alite or tricalcium silicate, a more rigid and less permeable material than lime.
You’re walking down the sidewalk and wondering why are they sectioned off in four food squares or six foot squares and that’s because Portland cement is very brittle and we have to tell it where to crack and where to go versus the lime buildings like the 19th Street Baptist Church. There are no control joints and things were able to move freely and accommodate small bits of movement because lime unlike Portland Cement has the ability to heal itself, something called autogenous healing.
This autogenous healing is part of why the 19th Street Baptist Church is still standing today but the original lime mortar is all but dissolved now and that’s why the building is crumbling.
Lime mortars as they age and as they wear, they’re meant to be replaced so there’s always a maintenance issue associated with them. I hope that there is a lot of architectural salvage that can occur to pay homage to the traditional materials that were originally by Frank Furness and his architectural team.
In essence they should be able to replenish the lime mortar in the structure, but after so many years of neglect it’s getting late in the game.”
Here’s a brief summary of the project at the First Congregational Church of Hudson (OH) project by John Burnell, Principal, Mason’s Mark LLC.
The church was originally built in 1865 in historic Hudson, Ohio. It was repointed several decades ago with a cement-based mortar and started to develop brick deterioration problems in both interior and exterior upwards of 10 years ago. We performed an extensive survey of the building in 2003 and were contracted to undertake removal of the cement beginning in 2010. We completed Phase 2 last spring and are scheduled to complete the tower this summer. We used NHL 2 which we custom-tinted to match the original mortar color, and for sections that needed some brick repair, we used custom-tinted Lithomex repair mortar and some of the custom tints of Silicate stain, both to match the color and patina of the original bricks.
We’re so proud to be part of an incredible restoration campaign currently taking place at the University of Virginia. The Rotunda is the focal point of Thomas Jefferson’s Academical Village at UVA and we have the pleasure of supplying our Ecologic™ Mortar for the repointing campaign. Below is an excerpt from the university’s website explaining the repairs that are currently taking place, also take a minute watch the brief video.
Preserving the Heart of the Grounds
The capitals atop the Rotunda’s columns were shrouded in protective netting after it was discovered that they were crumbling from age and a variety of other issues.
Thomas Jefferson intended the Rotunda, which he called a “temple of knowledge,” to be the centerpiece of the Academical Village; it housed the heart of the University operations—the library and classrooms. The Rotunda and associated grounds are now in critical need of extensive repairs. The renovation, which began in May 2012, will span several years.
What specific repairs and renovations are being done?
The Rotunda renovation includes extensive infrastructure upgrades and exterior repairs. The initial phases are addressing conditions that threaten the building’s integrity and include significant roof repairs, column capital restoration, masonry repairs, and window restoration. Panels in the Dome Room will be replaced with a better acoustical control system; lightning protection will be greatly improved; and a new elevator installed.
Later phases of the project will entail improvements to the Rotunda’s interior infrastructure and restoration of the surrounding landscape. The building’s aging infrastructure, including plumbing, electrical, audio/visual, heating/air conditioning, and fire protection, will be upgraded. Portions of the building may be adapted to allow for classroom use. The current total estimated cost is $50.6 million.
The Technical Install Team of LimeWorks.us was called in to reverse some of the inappropriate finish that had occurred over the years at this Historic New Jersey home. When the team arrived they found this 19th century brick home covered in layers of peeling latex paint and years of well meaning repair attempts using harmful Portland Cement based mortars and stucco.
Besides the peeling paint and gaping holes, water was trapped within the masonry walls which made it incredibly inefficient to heat which can often will lead to build up of mold growth within the building.
The LimeWorks.us Technical Install Team removed the layer of latex paint and localized areas of the Portland cement based materials which were contributing to an adjacent wall system failure. They repointed with lime-based Ecologic™ Mortar and applied Ecologic™ Mortar SCG (non-pigmented) as a stucco. Finally, the lime stucco was whitewashed using breathable St Astier Lime Paint “Natural” (non-pigmented) to finish the repair campaign with this traditional whitewash.
Q: There are some bricks in wall that are mismatched in color. Is there a way to have them match without removing them?
A: While this question comes up from time to time, most often people don’t know that they can easily remedy such a problem and don’t bother to ask. By using silicate stains many colors and variations can be achieved to change the color of masonry permanently.
These stains are applied with a simple foam brush when the bricks are clean and free of moisture. They can only be applied in weather conditions above 40 degrees (F). Prior to a repointing campaign, bricks can be very easily stained and then repointed to achieve a uniform appearance. Since silicate stains are acid resistant gentle masonry detergents can be used to clean smeared brickwork after repointing. Make sure that the silicate staining work is fully cured before any light cleaning, as necessary, so that there is no damage to the stained finish.
Example of brick stained in two different solid colors and 1 example modeled with three different colors to achieve a more distinctive distressed appearance
The historic Shirley Plantation is situated along the James River right outside Richmond Virginia. It was constructed in the early 17th century and is the oldest family-owned business in North America as stated on their website. Today, unfortunately much of the brick that makes up the various buildings is literally falling apart. Spallingof the brick faces is occurring in a number of areas. One major contributor to this problem was the use of harmful Portland Cement installed in previous repairs throughout the structures.
Preserving the irreplaceable brick is currently the top priority. One method that has been very successful is the use of a very simple and natural product called Ecologic™ Waterglass Primer & Consolidant for Masonry. This is a mineral-based fixative, conditioner, and a mild consolidating repair material, sometimes also referred to as a “liquid stone primer.” It can turn the once brittle and crumbling historic red brick back into a more substantial and solid masonry unit once again. The use of Ecologic™ Waterglass Primer for brick and stone consolidation will allow the masonry to continue to breathe and possibly achieve a permanent repair, if the root cause of the masonry decay is also addressed.
Click here for more information on Ecologic™ Waterglass Primer and our other mineral based paints and stains.