Preparation for Repointing Brick or Stone

How to Remove Mortar Before Repointing

The biggest challenge in restoring masonry walls and buildings is replacing Portland-cement-based mortars with a natural lime mortar. The difference between the two is easy to determine. Using a pointing chisel to remove lime mortar is quite easy; the mortar is soft and breaks easily in front ofthe chisel. Portland-based mortars are quite hard, and hand-chiseling takes many blows from the hammer to remove just a couple inches of joint.

This hard mortar is very damaging for brick and soft stone. One reason they are so damaging is that Portland-based mortars (Type N, Type S, and most mortars available today) are not water permeable, so they do not allow moisture to escape from the wall. Also, Portland-based mortar is not flexible, but brittle, so the masonry units are stressed by freezing temperatures and imperceptible building movements. This can take the faces of brick right off of buildings that should be preserved and protected. Natural lime mortar will wick moisture away, and flex with the small movements of temperature changes and settling that occurs in every building over time.

To remove Portland-based mortars efficiently, a grinder should be used to cut a groove in the center of the joint. Usually a thin blade works better than a thick one, and a 4" blade will cut through the Portland-based pointing back to the original lime-based mortar. Cutting the center of the mortar joints prevents slipups from damaging the original brick or stone. Special care should be taken on head (vertical) joints to cut only as deep as the grinder can without cutting into the masonry units. This can take strength and focused attention because the grinder is harder to control when removing very hard material. Center-cutting the joints relieves the pressure that the hard mortar puts on the faces of brick and stone.

The second step is to hand chisel the joints out. Usually the best method is to place a flat chisel right where the mortar meets the edge of the brick or stone, aiming toward the center groove that was cut with the grinder. A pointing chisel can also be used to go across. Pick a 2"or 3" section of joint and aim the pointing chisel toward the area that has already been removed. The chisels will break the bond between the Portland-based mortar and the brick or stone.

Usually the repointed joints are less than an inch deep, so removal is safe as long as care is taken with the faces of the masonry units. Remove mortar at least 2x the height of the joint. A 3/8"-wide joint should be chiseled back to at least 3/4". This will ensure an adequate bond between the new mortar and the brick or stone.

Once the mortar is removed, the joints should be vacuumed, or blown out with compressed air. A low pressure jet of water, such as from a nozzle on a garden hose, can also be used. If the joints are vacuumed or blown out, it is a good idea to dampen the wall before applying the new mortar.

Never use a pressure washer on soft brick or stone. High-pressure water can damage walls of even hard stone (like granite), so the nozzle should be kept well back from the face of the stone. Pressure washers often remove the beauty of the weathered faces of stone, including the green moss that can make a building look old.

Imitation Slate

Re-roofing with imitation slate

Imitation slate is a less-expensive option for a roof that looks like real slate and is acceptable in almost every city for use in historic districts. Imitation slate also weighs less than real slate, which is a benefit for older homes with questionable roof structures.

There are basically two companies that manufacture imitation slate, and both come with good warranties when installed by a certified installer. One is Eco-Star Majestic Slate by Carlisle and the other is Lamarite Slate Composite Shingles by Tamko. It is a personal choice in Reading, Pa, as to which brand to install because both have very good warranties as well as similar characteristics.

Both brands come in various options, such as color, width and style. If your home is a Victorian Style, perhaps the beveled, beaver tail or chiseled point from Eco-Star will your best choice. Keep in mind though, that whether you pick real slate or imitation slate, the snow will slide off fairly easily, so you should spend the money for the correct snow guards or during winter someone could get hurt or damage to the roof gutters can occur from falling snow.

If you ever need to physically get onto your real slate roof, you must be careful of breakage; with composite or imitation slate there is no need to worry about breakage, as they are unbreakable!

Whichever brand of imitation slate in Reading, Pa you wish to have installed on your home, make certain the installer follows the manufacturer's installation instructions closely, and you will have a roof that will last and look great for many years.

Contact Brookline Builders of Lancaster, PA, for a estimate for your imitation slate roof.

Installation of Imitation Slate

Installation of Imitation Slate -- Brookline Builders

Imitation slate must be installed carefully following the manufactures instructions or the manufacture will not give you a warranty. Most imitation slate manufactures offer at least a 50 year material warranty, but if the new imitation slate tiles aren't installed exactly as specified in the installation manual, you will be on your own if the shingles fail.

Did you know that most old existing slate roof's were installed over roof sheathing made out of random width boards that were not tongue and grooved? In order to meet most manufactures specifications, the imitation slate shingles will not be warranted if installed over this type of sheathing. Don't be caught by surprise. If you go into your attic and can see that there are gap's wider than 1/4 inch between the sheathing it will be nessary to install 7/16" OSB or 1/2" plywood over the existing sheathing. This will make sure the nails grip the sheathing properly when installing your new imitation slate roof.

The nails spec'd for proper installation are very expensive, not your common galvanized roofing nail. These nails are ring shanked stainless steel. These nails will still be holding strong even after 50 or more years as stainless doesn't rust and the ring shank will keep them from pulling out. Standard roofing nails cost around $30 - $50 per case, these manufacture spec'd nails will cost close to $300.00 per case.

There are several installation patterns and styles available. Some manufactures offer up to three different widths for their imitation slate tiles. Although a random look may look very nice as a finished product, the installation of this random style requires more labor. Remember, the more random the pattern, the more labor and thus a higher cost for the installation. You can check out the EcoStar installation instructions here.

Imitation Cedar Shakes -- Lancaster, PA

Imitation Cedar Shakes -- Lancaster, PA

For complete installation of imitation cedar shakes, contact Brookline Builders. Although real cedar shakes are beautiful, they don't last as long as imitation cedar.

Imitation cedar shakes are made out of a composite material and offered by several companies, DaVinci, and Tamko's Lamarite Shake, Enviroshake and Carlisle.

Imitation cedar shakes can be installed in a random pattern or in traditional styles.

Contact Brookline Builders for all your composite or imitation cedar shake installation needs.

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