Choosing a Mason in Lancaster Pa

Choosing the right masonry contractor in Lancaster, Pa. has gotten a whole lot easier if you have an historic home built before 1900. Brookline has all the historic trades in-house to completely restore your historic home. Brookline is a masonry contractor in Lancaster, Pa. that has skilled masons fully trained in the use of historically-compatible mortars, including locally-made lime mortar.

Lime mortar is not a simple matter. Lime was the only binder for mortars 120 years ago, and is superior to Portland cement in every way except one: speed of hardening. Portland cement was invented and adopted for one reason only, and that is that masons can lay more wall in a day's time because it sets up quickly.

Speed is an advantage. Being able to go fast is superior. But in every other way, Portland cement is inferior to a lime-sand mortar. Portland seals water into a wall, deteriorating the masonry and other building components. Portland destroys historic homes fast.

Having a masonry contractor who knows this is priceless. So many contractors today are uneducated about lime mortar, and how important it is for historic brick and stone. Brookline uses lime putty from Lancaster Lime Works in Lancaster, Pa. to make all of its mortars for restoration of historic homes. The training that Lancaster Lime Works provides can help any masonry contractor to understand the full options when it comes to mortar.

There are many ways to make mortar besides opening a bag and adding sand and water. Knowing the different binders that are available today allows a masonry contractor to make intelligent choices about the mortar that is used in a particular construction situation.

The most important factor in a mortar is breathability. Masonry contractors must have an idea of the vapor permeability of the product they are using for restoration of historic masonry. Using Portland cement to restore any historic masonry will cause damage that cannot be repaired. That is why it is so important to choose a masonry contractor that knows historic mortars.

Brookline is a masonry contractor in Lancaster, Pa. that specializes in historic masonry restoration and historic mortars.

Brick Repairs in Lancaster Pa.

Historic brick needs to be repaired sometimes. Sometimes the mortar gets loose and falls out. Sometimes the face of the brick erodes or falls off, and sometimes bricks just get loose and fall out. In Lancaster, Pa. we see these situations everywhere we go to do work. So many historic brick homes need brick repairs, and there are not many masons out there who are skilled at brick restoration and brick repairs.

We see so many sloppy brick repairs and brick replacements on historic homes that are done with modern brick. These kinds of unskilled repairs stand out to the experienced and inexperienced eye alike--they are unsightly.

Brookline performs historic brick repairs throughout Lancaster, Pa and the surrounding areas. We have done brick repairs in Washington, D.C., Gettysburg, York, Philadelphia, and everywhere in between. One of the most common places for bricks to need repair and replacement is on chimneys. Brookline repoints and rebuilds these chimneys.

We do not use any Portland Cement for historic brick repairs. It does not matter how much Portland a mason mixes into the mortar--it will seal in moisture, become brittle, and start deteriorating the brick within just a few months. It may take a couple years to you start seeing it, but it will show. Even a Type O or Type K mortar, which is a very weak Portland mixture, will trap moisture, deteriorate bricks, and crack.

Lime mortar is what Brookline uses for historic brick repairs. Lime mortar is mortar made from high-calcium lime putty, which is completely different from the Type S (mason's) lime that you find at the builders' supply houses. We never advise using mason's lime for brick repairs.

Use only lime mortar, such as can be found from Lancaster Lime Works in Lancaster, Pa. It may be more expensive, but in the long run it will save tens of thousands of dollars in repairs, brick replacement, and hassle. Lime mortar won't crack and fall out, and it won't cause peeling paint, mildew and mold, and moisture problems on the interior of the building like Portland does.

Mold, peeling paint, and rotten wood on the inside of the historic brick or stone house is usually caused by Portland cement mortar used in the pointing or the stucco on the exterior. The moisture has no way to get out of the wall. It has to go out somewhere! Portland cement will cost much much more than it saves when it comes to brick repairs, brick repointing, and brick replacements.

A Few Advantages of Lime Mortar

The core of Brookline's masonry preservation division is our commitment to using lime mortar for all historic structures. Lime mortar has many advantages over Portland cement.

Here is a short list of just a few advantages:

Lime mortar is more flexible and less brittle.

If there is building movement, lime mortar will eventually re-seal the cracks in the mortar. Having a softer mortar means soft bricks and stones won't be forced to break. The mortar is the "sacrificial component" of any masonry wall. With Portland, the mortar is so hard that it chisels off the faces of the bricks with even the slightest building movement >i>and all buildings move.

Lime mortar is breathable, which means that moisture that gets in the wall (from damp conditions inside or outside) will escape rapidly. Portland cement seals moisture into a wall, causing mold problems inside, deterioration of wood, and deterioration of the bricks or stones themselves.

Lime mortar still sheds water from rain just as well as Portland cement.

Lime mortar will last longer than Portland cement. Lime mortar that is made from 98% pure calcium will last 100 years minimum. Portland cement mortar lasts about 50 years, and sometimes cracking and deterioration is visible within 10 years. Portland cement degrades from the inside out because of impurities like aluminum silicates. These impurities cause it to get hard fast, but also cause it to deteriorate fast.

Because lime mortar is softer, it can be removed easily, without damaging the bricks or stones. Portland mortar is so hard that it is very difficult to replace without breaking or de-facing the bricks or stones, even if it is badly deteriorated.

Contact Brookline today for your city brick restorations or city stone restorations in Lancaster Pa and surrounding areas.

PA Home Improvement Contractor License number PA1840

Here are a few of the questions from homeowners that we get on a regular basis.

Nothing bothers me as a homeowner worse than seeing cracks in my brick joints and joints that have completely fallen out. I have to look at it day after day, and I am afraid that water is coming in those joints.

I have an old brick home. I would even call it an historic brick home. It was built sometime in the 1800's, but I don't know when. Somebody repointed some of these mortar joints at some point with some ugly, gray mortar that doesn't match at all.

Now I read that Portland Cement damages old historic brick homes. I want to get this Portland Cement mortar out, and put the right stuff in. The faces of my bricks are starting to crack and fall off. Is this what you call spalling?

How do I find out what is the right mortar for an historic brick home? I want some repointing done, but every mason that I talk to uses regular cement for the pointing. I need a good city brick restorations company in Lancaster PA. I want to use something that more closely matches the original mortar for pointing. Does Brookline do repointing? Is your lime mortar going to match my mortar, and will it last a long time?

If these are the kind of questions you have regarding your old brick or stone home here in Lancaster Pa contact Brookline Builders today.

MORTAR FORMULA AND SAMPLE

MORTAR FORMULA AND SAMPLE

1. Before commencement of any removal of existing mortar, Contractor will collect a sample of the original pointing mortar.

2. Mortar sample shall be analyzed chemically to determine the actual ratio of sand, lime, and other materials in the mortar mix.

3. Mortar formula shall be provided to the customer.

4. Prior to start of the work, a field sample panels shall be prepared to demonstrate: Protection of adjacent masonry from damage. Containment of debris. Masonry cleaning by hand and by mechanical methods. Cutting and removal of existing mortar. Cleaning and preparation of the joints to be repointed or re-bedded. Installation of bedding and pointing mortar. Finish color and texture of joints to be repointed, using provided formula.

5. Prior to start of work, Contractor shall obtain approval of sample panel from Customer.

BRICK AND MORTAR BASICS

BRICK AND MORTAR BASICS

The following provides an overview of the characteristics of brick and mortar, and how they sustain unnecessary damage through improper maintenance. This is provided to assist in understanding the masonry sections of this report. A more thorough comparison of Portland mortar and hydraulic lime mortar will be found in some of our other blog posts.

Bricks that were used in the construction of the original older buildings were fired at lower temperatures than modern brick. They do have a hard exterior, but are still much more porous (absorpent to moisture) than modern bricks. If the harder face of the brick is removed by sandblasting, the much more porous and fragile interior of the brick is exposed to the weather. Sandblasting was widely accepted in the past as a way to clean dirty, painted, or stuccoed brick. It is now widely known to significantly weaken brick's resistance to damage from weather.

The original brick building walls were laid with hydraulic lime mortar, which has been in use for around 7,500 years. It is made by burning limestone, and it gets hard by going through a chemical reaction with water. It is very different from the Portland cement mortars used over the last 100 years. Portland cement is much harder, less flexible, and is completely non-porous. Portland cement mortars are now known to threaten the longevity of brick and stone walls, and can greatly accelerate damage to soft brick.

Moisture from the weather, both humidity in the air and precipitation, penetrates bricks and stones in a wall because they are naturally porous. This moisture in the bricks can cause rapid damage to the bricks if it cannot escape quickly, especially in freezing weather. Hydraulic lime mortar allows moisture to escape very quickly out of a wall. Portland cement traps moisture in the wall. Moisture that is trapped in a brick wall causes the brick faces to break off, leaving a rough, ugly, fragile exterior. It also causes moisture problems on the interior, such as plaster decay, stains, and wood rot.

Walls that are constructed of older, softer brick should be repointed with hydraulic lime mortar, never Portland cement. Walls that have been repointed with Portland-based mortar should be repointed with hydraulic lime mortar. Brick faces that have been severely deteriorated can either be repaired or replaced. Replacement of the bricks can be done by finding new bricks that match, or by removing and turning around the original bricks. Damaged bricks can be repaired by using Lithomex, a flexible, porous, lime-based material that is applied in lifts to the face of the damaged brick bringing it back to its original shape, size and color. It bonds with the damaged face of the brick, and becomes a permanent repair.

Old and damaged bricks can also be removed from the wall using special tools. Sometimes the damaged and spalling bricks can be removed, turned around and reinstalled. Others will be so badly deteriorated that they will need to be replaced entirely.

The method of removal for existing Portland-based mortar is extremely important. Using a grinder will create a lot of dust, and the spinning diamond blade very easily causes irreparable damage to the face of the old brick. We suggest using a power tool called Arbortech, along with a high quality vacuum system. It has two vibrating blades that act like scissors, cutting into the Portland-based mortar and greatly minimizing potential damage.

Hydraulic Lime Mortar On a Chimney Cap?

As a company, we are committed to the challenge of using sustainable building methods in our historic restoration projects. Sometimes we are asked specific technical questions as to how these two objectives are reconcilable--how can we use historic methods over modern techniques to stand the test of time? Recently, we received just such a question: "I am committed to using the sustainable and historically accurate natural hydraulic lime mortar on my chimney cap, but how will the natural lime mortar hold up in the long run?"

This is a valid question. After all, Portland is harder than natural lime mortar, right? So although it is historically accurate, how is it sustainable to use a softer material on a chimney, one of the hardest to reach places and one of the most vulnerable spots on your historic house? Shouldn't your chimney, of all places have a durable and water proof cap? Beautiful homes, that have been meticulously maintained, have often been found to have small plants growing out of the chimney.

First let's consider a few of the attacks a chimney has to endure. The most obvious is the extreme exposure to all forms of moisture: rain, snow, dew and frost. Constantly varying temperatures throughout the year, from cold winter nights to scorching hot summer days add an additional assault on the chimney--the constant expansion and contraction takes its toll. In the dead of winter, when the furnace kicks on and 400 plus degree air suddenly hits a 15 degree chimney flue, then what happens? The resulting pressure has an effect much like putting an untempered glass into a hot oven: it cracks. This expanding and contracting phenomenon has another destructive effect; the clay liner which your chimney is built with will expand upward as it heats up then contract back down as it cools. This effect may further compromise your chimney's structural integrity. As if this was not enough, a surprising attack comes from another part of nature. A chimney is a natural resting place for birds. We have seen the corrosive effect that bird droppings have on the integrity of a chimney cap. While we won't attempt to address all of these issues here, we will address the basic way that we apply a chimney cap.

Needless to say, the chimney has a very difficult and challenging life and it would be advisable for the responsible homeowner to inspect a chimney for integritymuch as he would inspect his gutters for leaks. Just as a leaky gutter will ultimately wreak havoc on any masonry construction, a leaky chimney will do the same. Add the chimney cap to the schedule of five year maintenance checks. Eventually, you may have to repair it, or even replace it completely. As I like to say, a chimney cap replaced in time can save nine.

So, now let's go back to the historical use of hydraulic lime mortar on the chimney cap instead of Portland. Portland is harder and water proof right? Doesn't that mean it will last longer, and need fewer repairs? It's a good theory. But there are more destructive forces at work on a chimney cap than just moisture.

Recall our description of one of the most destructive attacks: thermal expansion and contraction from the flue gasses as they heat a very cold chimney. Portland may be harder, but hardness doesn't handle that kind of expansion very well, it cracks easily and once it cracks it doesn't heal. Earlier, we raised a concern that natural lime mortar is softer, right? But now we see that the softness is a positive thing because it will permit more movement than Portland. If it does crack, it heals itself! This is how it works chemically: the content of natural free lime actually attracts to itself and thus it self-heals, sealing the crack.

The tried and true method we use to apply a chimney cap is as follows:

We apply three coats of mortar. The first two coats consist of two parts course concrete sand, one part 3.5 natural hydraulic lime mortar, and one handful of natural hair or fiberglass. The third and final coat we apply is proportioned as follows: two and one half parts sand, one part 3.5 natural lime mortar, this final coat has a bit more sand; no fiberglass or hair. This method will allow the first two coats to act as a stronger mixture--the fiberglass acts as a rebar of sorts-and the final layer seals the fibrous ends so they won't act as a wick for water absorption; we don't want a conduit for moisture. For a few weeks after the new chimney cap has been applied, it should be covered from moisture-depending on the temperatures-and should be kept damp in hot temperatures.

While the exact method of applying a new chimney cap may vary extensively, we have found that our method works quite well and lasts for many years. It is our commitment to balance the use of natural and sustainable products, while enabling the use of historically accurate products and procedures.

Chimney Repointing

Brookline Builders will repoint and rebuild your old chimney with Natural Lime Mortar. The reason most chimneys fail is because of water penetration. If a cap of either flagstone or metal is maintained and installed on your chimney, the water will not penetrate and your chimney will outlast the roof. If water is not kept out of your chimney it will deteriorate extremely fast, especially in the winter during freeze thaw cycles. If your chimney needs to be rebuilt don't ever use portland based mortar, especially on a chimney.

Portland will not withstand the expansion and contraction of an exposed chimney, it will crack quickly then fall apart in just a few years. This is because portland based cements are water proof, so once the water penetrates into the chimney, and it will, the portland does not allow the moisture to escape. This moisture that is trapped in the exposed chimney will expand when it freezes and thaws. Over a few years the effect of this cycle the chimney will blow apart.

The key to repointing an historic chimney is to not use any portland cement. Rather use natural lime mortar. Natural lime mortar will allow trapped moisture to quickly escape and will self heal any cracks. The pyramids in Egypt were built using natural lime mortar. Portland cement wasn't widely used in the US until the early 1900's.

Hydraulic Lime Mortar Contractor -- PA

Mortar and Longevity: Will Our Buildings Stand the Test of Time?

Did you ever look closely at the exterior of brick or stone home, and see hairline cracks running up the wall? Or sometimes the mortar joints have lots of cracks running across them, so that the mortar looks like it could fall out in 3-inch sections. Even an old (or not so old) concrete block building, like a garage, can have joints cracking out all over the place.

Natural Hydraulic Lime Mortar

Whether your a homeowner, or someone in the building trades, you may have noticed mortar joint failure, and maybe you had a thought like, "What is going on here? I thought masonry was the best exterior-supposed to last forever!!!"

Isn't a stone home supposed to last forever?

What about the castles in Scotland and the palaces in Prussia??

We are stonemason's, and these are questions we have started to ask also. For us, our livelihood depends on the answers because we can already see cracked mortar joints in work we did 5 years ago! Could the mortar that we were trained to mix and use be flawed?

Why do patios and sidewalks crack so quickly-often in less than 10 years? Why does almost every stone, brick, or block building show cracks in just a few years after it's built? That's not the longevity we expect from using such historic and time-tested materials!

Materials scientists have been asking these same questions. After studying those castles in Scotland and masonry buildings all over the pre-modern world, the answers are starting to come out. Turns out the mortar we use today is not at all historic. Time has tested it, and it is failing the test.

A little construction history might help at this point. For at least 7,500 years, man had been using (roughly) the same process to make mortar: burn high-calcium limestone by layering wood and stones inside of a really fat chimney (kiln) and then lighting it on fire. The resulting burnt stones are then crushed and mixed with sand and water to make mortar. The burnt lime reacts with the water, causing it to get sticky and then harden, lasting for centuries or longer in between the stones in a wall.

This lime is called hydraulic lime because it hardens without the presence of air. Getting hard is a chemical reaction that is different from just drying out. It will get hard under water.

Now don't confuse hydraulic lime with hydrated lime. Hydrated lime is a different process, a different material altogether. Hydrated lime can't be used as the binder in mortar because it never gets hard. Hydraulic lime does.

Now, jump forward in the history of mortar to the late 1800's when various inventors began experimenting with new processes and materials for making cement. Portland cement, the almost exclusive binder and hardener in today's mortar, concrete and stucco. It got its name from the Isle of Portland in the English Channel where limestone had been quarried for centuries and admired for its building qualities. By 1878, the British government had issued a standard for Portland cement, and in 1907, production began in the United States. It came to be the main ingredient in mortar and concrete throughout the country by the end of World War II.

Now, Portland cement has proven its superiority to hydraulic lime in many departments.

In the speed-of-getting-hard department: Portland's the champ.

In the waterproof department: no contest. Portland wins.

In the hardness department: Portland wins again.

Game over? Not yet.

As it turns out and according to research on the old hydraulic lime mortar, using Portland may be a strategic error. At least, as far as longevity is concerned.

It all boils down to the way we think about buildings and how they weather. Everyone knows that the point of a building is to keep out water, right? In recent decades research on building materials and techniques has gone farther and farther down the road of keeping out 100% of all moisture and all air. Now we are combating mold, air quality, and condensation problems.

But back to the Portland vs. hydraulic lime debate.

In the longevity department: no contest. Hydraulic lime wins. Hands down. Why?

Yes, Portland cement seals out water. Hydraulic lime allows water to penetrate. The problem is that most masonry units (like brick, stone, and block) absorb small amounts of moisture from the air and rain. Hydraulic lime acts like a wick to get that water back out-- FAST!! Portland won't let the water pass, trapping it in the wall where it does damage-cracking the joints and even the faces of the bricks or stones. That's why you see the faces of old brick buildings popping off. Repointing with Portland destroys the building-FAST!! Repointing an older building using portland cement starts the countdown to it's demise.

Yes, Portland cement is harder. But harder is also more brittle. Portland is fired at about 2,600 degrees Fahrenheit, as compared to hydraulic lime's 1,800 degrees. When you look at the two under a microscope, hydraulic lime particles are like plates that interlock; Portland's are like needles. Any movement in the building is going to make Portland crack all over the place, while the more flexible lime mortar can move with the building without cracking.

It gets better.

When you get down to the microscopic level, Portland cement has salts in it that actually degrade the mortar from the inside out. This stuff starts decomposing as soon as it gets hard!

You guessed it: hydraulic lime has a little secret of its own, and its not the kind that brings the wall down. Hydraulic lime has small amounts of free lime-lime that never reacted with the water in the beginning, after it was burned. This free lime actually dissolves in the water that is escaping out of the wall, and in the process it fills any cracks that may have formed. The experts call it "autogenous healing." Like a lobster growing back its claw, I guess.

No wonder they used it for 7,000 years, Plus.

No wonder the historic restoration movement is switching from Portland-and-lime mortars to historic, hydraulic-lime mortars.

Hydraulic lime is still a bit hard to find in this country. To my knowledge it's not produced in the U.S. yet. What we use is imported from France. Different grades can be used to make plaster, stucco, lime paint, mortar, and even concrete.

So next time you're wanting you're chimney repointed, a stone or brick historic building restored, find a historic restorations contractor who knows about hydraulic lime. As a mason, the choice is clear to me. What's the point of building new or restoring the old, if our work is not going to stand the test of time?

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