PRESERVING YOUR BUILDING

AN EASY GUIDE TOEXTERIOR BUILDING MAINTENANCE
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Dear Reader:

Whether you know it or not, you are your own best building maintenance asset. You have first‑hand knowledge of your building and can keep track of its condition better than anyone.

ARTISAN is pleased to present you with our Easy Guide to Exterior Building Maintenance. We have developed this Guide to familiarize building owners, boards and managers with a building's exterior protective system and to highlight particular areas that demand frequent inspection.

The Guide explains waterproofing and roofing processes and outlines a simple and thorough building inspection procedure. The Guide will help you better examine your building exterior and prevent needless building repair expenditures.

Please use this Guide as a handy and comprehensive tool to aid you in the earliest detection of leaks and building exterior deterioration. Of course, don't hesitate to call us at 212 366‑9666 if you have a specific question or problem.

ARTISAN has been serving the greater New York area since 1987, and we welcome the opportunity to respond to your questions and work with you in the management of your building exterior maintenance program.

Sincerely,

Gary Zaremba

President

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Deterioration of your building is a continual process; however, there are ways to protect your building and ensure its health.

The exterior envelope is the primary protection of a building and is usually first to fall. Deterioration can occur through neglect or simple wear and tear. However, once it has occurred, damage to the entire building begins.

When the exterior envelope is deteriorated, water enters a building. It corrodes, rusts, and rots various structures and expands and contracts in the winter damaging masonry, mortar, and balconies and protruding appurtenances. Water saturates insulation, waterlogs and destroys the roofing system and drips into apartments. Ceilings and walls are usually ruined.

You will find that most damage occurs at the top of your building and that the roof is the most vulnerable point of entry. As a result, this is the area that demands the most attention and upkeep to remain watertight.

If minor leaks are left alone, they usually lead to major problems, which are extremely expensive to repair, especially if complete roof and parapet replacements are required. Some leaks and building faults are unavoidable, but with proper care most leaks can be prevented quickly, easily and cost‑effectively corrected.

Effective waterproofing and roofing are accomplished when a building has sound masonry, masonry joints and a properly installed roofing system. This creates an exterior building envelope, which protects outer and inner building structures from environmental forces and ensures the health and longevity of a building.

Maintaining a watertight building exterior requires care and attention on the part of the owner, board, manager and superintendent. Attention to your building pays off because it usually prevents extensive and costly damage.

Since the adoption of Local Law 10, some building owners feel that their building exterior is receiving more than enough attention; owners vie, “The once‑every‑five‑year inspection required by the Law as an effective maintenance program for the facade, roof and complete exterior of their buildings. What these owners may not realize is that Local Law 10 was designed specifically to protect pedestrians, not the owner's property investment.”

Local Law 10 inspections focus on dangerous conditions of the building facade and do not comprehensively covers other areas of deterioration, decay and water leakage. As long as facades facing public walkways are not dangerous, a building may receive a "safe report.” However, a building could be suffering from leaks in areas other than the façade, which are not noted in the report. These leaks can soon produce dangerous conditions.

Local Law 10 inspections are an important part of a building's preventative maintenance program, but they are only one mechanism to monitor a building's condition. You must decide how you are going to monitor and maintain the condition of your building on a regular basis.

Retaining a contractor to perform periodic inspections may be one effective measure to implement. Your participation and that of your managing agent, in the inspection process is another important component in a maintenance program.

Our guide offers you an effective maintenance tool. It provides you with information and checklists you and your staff can use to perform your own comprehensive inspections and these regular self‑inspections may be used in conjunction with periodic or specific problem‑related inspections by a contractor.

Editor's Note: We have included a handy glossary of technical roofing and waterproofing terms. Use the glossary whenever you find an unfamiliar word.

The purpose of regular inspections is to detect, monitor and record any changes or deterioration that takes place in a building. Most problems can be detected visually. You should begin your inspection at the top of your building, paying special attention to the roof, and then move downwards. You should test any mortar appearing to be faulty by probing with a simple penknife or pencil. Never probe the roof surface for any deterioration or irregularity could identify a more serious problem and should be left alone until looked at by an expert.

● When walking over the roof area or scanning the walls of your building, you should be looking for any irregularities, signs of change, decay or wear.

● If you can crumble or crack any mortar, masonry, wood or sealant by rubbing it, it is faulty.

● In most post‑war buildings, there is insulation beneath the roof membrane, which soaks up and retains leaking water like a sponge and creates a waterlogged roof, which usually demands total replacement.

● Bricks and masonry breathe; water enters and leaves bricks naturally. When bricks get old, they become porous and water continuously enters the brick and eventually enters the structure.

● The roof is not a traffic area; even maintenance traffic should be strictly limited.

● Special attention should be paid to anything going through the roof, such as supports, plumbing, skylights or bulkheads. These are areas which are prone to leaks.

You should visually examine the entire roof, taking tune to survey all areas. Every part of the roof is important. Be sure to check all the out‑of‑the‑way places. The roof should feel solid as you walk over it; if there are any depressions or soft areas, they probably indicate a problem beneath the roof membrane. Any mold or organic growth on the roof should be seen as a danger signal; it means that either the area is porous or that it is holding water.

A thorough examination of the facade and walls of the entire building is crucial to detecting early signs of deterioration. Binoculars and a telephoto lens are the most effective visual inspection tools. You should pay attention to shifting of wall sections, cracks, holes, missing or weathered mortar joints and stains, which indicate problems in water drainage.

Be on the lookout for any masonry decorations, appurtenances or balconies, which might be decayed or cracked at their joints. These protruding building parts receive a lot of environmental wear and, if they deteriorate, they may fall and strike someone or something.

What follows is an area‑by‑area inspection guide. Fifteen specific exterior building areas are defined and a handy checklist follows each area description.

Roof Surface: Ideally, the surface of a roof should be solid, resilient and free of any decay or debris collection. The roof surface is a high-risk damage area, which should not be subjected to needless abrasion or extra wear. A roof should not be traveled by tenants; even workmen should be limited in their travel over the roof. If workmen cross the roof frequently, there is a good chance that a sharp object will be dropped and perforate the roofing envelope. If building repair requires traffic over the roof, special protective walk‑pads should be installed. The roof deserves the most frequent general overview and examination.

Drains: Drains and drain mouths are the initial exit points for rain water from the roof and must be examined and cleared of all debris frequently. Protective drain coverings aid in easy cleaning and prevent internal dogging and destructive back ups. Screens must be properly sized and cleaned to maintain a free flow of water. If drains are allowed to clog, water will back up and pond; ponding water often rises above base flashing and flows freely into the interior structure, seriously damaging the entire building.

Base Flashing: Flashing seals the roof membrane at walls and other interrupted roof areas. Flashing connects the horizontal portions of the roof to the vertical portions. They are a piece of roof membrane, metal or copper in the shape of a 90-degree angle, which is sealed to the roof interruption. The horizontal portion is built into the roof system and the vertical portion sides the roof interruption and is covered by a cap flashing. Flashing is often missing, deteriorated or open at their seams, so you should pay special attention to their condition. If they have been torn away and resealed, you should check that the seal is sound and intact.

Cap Flashing: Cap flashing are pieces of metal or copper which protect the base flashing on a roof; they are the reverse angles of the base flashing. You should make sure they are in place and are properly overlapping the base flashing.

Terraces: The roof membrane on terraces is protected by walk‑ways and traffic‑bearing surfaces; for example, exterior tiles, cement blocks or routine walk boards. These should be checked for open tile joints, spalled surfaces, improper drainage and unsound expansion joints. An exposed roof surface should never be considered traffic bearing surface or walkway.

Gutters and Leaders: Leaders bring water from gutters to ground level and direct it to drains. Leaders should always be securely fastened to the side of the building. If they are faulty, split or clogged they will allow water to damage the building. You should also be on the lookout for any sags, bends or seam problems. Dripping water is an obvious catch sign of gutter or leader damage.

Parapet Walls: Parapets are the portions of wall, which extend above the roof; they are subject to extensive weather abuse and are very commonly the source of leaks. This area is easy to check and warrants frequent examination. Parapets should be checked for open mortar joints, decaying pointing, structural cracking, horizontal dislocation and corroded supporting steel.

The inner walls of parapets should never be covered with the roofing surface; however, they often are. In older buildings, the masonry on inner walls of parapets has often been tarred as a means of waterproofing failing bricks and mortar. Tarred parapets indicate that there was a problem in the past and that it has been insufficiently corrected. Tarred bricks cannot breathe and deteriorate quickly. If your inner parapet is tarred, you should dedicate extra‑special attention to it and consider eventual removalof the tar and restoration of the parapet.

Coping Stones: Coping stones lie on top of the parapet, protecting bricks and in structure from precipitation and environmental damage. They are most commonly made from pre‑cast concrete, but slate and clay tile coping stones also exist. Both concrete and slate copping stones become porous with age, at which point they require sealing with waterproofing cement grout or aluminum. Clay tile stone surfaces may wear off, in which case they, too, must be sealed.

The joints between coping stones should be sealed with expanding caulking. You should double check all joints to see that they are not separated from the stones and that they are still elastic.

Masonry Walls: Masonry walls should always be on a single plane; any area which is sticking out or in any way bulging or protruding should be immediately examined and attended. Scan all masonry walls for spalling, worn or cracked joints, open expansion joints and stains or weather discoloration.

Projecting Cornices: These are the greatest structural hazards because they are in a position to fall to a street or walkway because they jut out from the side of the wall at the top of the structure. Originally made out of copper or stone, cornices were designed to keep water from running down the side of a building. These are areas, which Local Law 10 was specifically designed to examine.

You should look for corroded flashing deteriorated interior steel, deteriorated copper skin, broken, loose or spalled terra cotta or masonry units or structurally unsound anchorage.

Water tables are stone bands or a sort of midway cornice which run through masonry was for aesthetic architectural purposes. They are often areas of deterioration and can be dangerous, too. You should check them for spalling open joints or missing stone units.

Stacks and Chimneys: Metal stacks and masonry chimneys take the same abuse as parapets because they are fully exposed to the weather. You should check for any structural movement, metal cap deterioration, displaced masonry or defective pointing.

Windows: Windows should operate properly, dose all the way and be draft‑free; frames must be periodically examined, repainted and resealed with glazing; the joints between glass and frames must be effectively glazed to retain heat and retard moisture penetration.

The caulking between window frames and masonry must be thoroughly examined for soundness. This caulking is often allowed to age and deteriorate and many leaks occur in this area.

Sills: Exterior sills and window frame sills are made from either wood, slate masonry to stone. Wood and metal sills must be painted and the paint must be in good condition; all sill joints must be sealed. You should watch out for open cracks or bed joints, spalling of surfaces or any horizontal displacement.

Wood Structures: Wood structures are not obsolete; they are used in both old and new buildings. You should examine all wood to see that it is properly painted or watersealed; be on the lookout for any signs of shrinking, splitting, and structural separating and joint gaps.

Appurtenances: Masonry decorations, gargoyles and balconies often become damaged at their joints. If their supporting structures joints or masonry deteriorates, portions may fall and strike someone.

Aggregates ‑ Gravel, crushed ‑stone, slag or mineral granules either embedded in a conventional built‑up membrane's bituminous flood coat or applied to a loose‑laid roof system as protective ballast. Aggregates are divided into two sizes ‑ fine and coarse.

Alligatoring ‑ Deep shrinkage cracks, progressing down from the surface in smooth surface membrane coatings and sometimes in bare spots of aggregate surfaced membrane it is a consequence of hardening from the sun and air.

Appurtenance ‑ Any architectural structure, whether decorative or functional, which protrudes from the exterior of a building.

Asphalt ‑ Dark brown to black, highly viscous, bitumin produced from petroleum, used as the waterproofing agent on built‑up roofs.

Backup ‑ That part of the masonry wall behind the exterior facing and consisting of one or more widths of thickness of brick or other masonry material.

Ballast ‑ Aggregate, concrete pavers or other material designed to prevent the wind from lifting a loose‑laid roof system.

Bitumin ‑ Generic term for an amorphous, semi‑solid mixture of complex hydrocarbons derived from petroleum or coal. Asphalt and coal tar pitches are the two basic bitumins of the roofing industry.

Blister ‑ Spongy, humped portion of a roof membrane, formed by trapped air vapor under pressure, with the blister chamber located either between felt plies or at the membrane substrata interface.

Brick (common) ‑ Any brick made primarily for building purposes and not especially treated for texture or color, but including clinker and over‑burnt brick.

Brick (facing) ‑ A brick made especially for facing purposes, usually treated to produce surface texture or made of select clays or otherwise treated for texture or color.

Built‑up‑roof‑membrane (BUR) ‑ Continuous, semi flexible roof covering of laminations or plies of saturated or coated felts alternated with layers of bitumin, surfaced with mineral aggregate or asphalt materials.

Cap sheet - Mineral‑surf aced coated felt used as the top ply of a built‑up roof membrane.

Coal tar pitch ‑ Dark brown to black solid bitumin obtained from coal tar, used as the waterproofing agent of a dead level or low‑slope built‑up roof.

Coated felt (or base sheet) ‑ felt that has been saturated with asphalt and later coated with harder, more viscous asphalt, which increases its resistance to moisture.

Cold‑process roofing ‑ Bituminous membrane comprising layers of coated felts bonded with cold‑applied asphalt roof cement and surfaced with a cutback or emulsified asphalt roof coating.

Caulking ‑ The operation or method of rendering a joint tight against water.

Coping ‑ The material or member used to form a capping or finish on top of a wall to protect the masonry below by throwing off the water.

Course ‑ One of the continuous horizontal layers or rows of masonry units which, bonded together, form a masonry structure.

Delamination ‑ Separation of felt plies in a built‑up membrane, separation of insulation boards into horizontal strata.

Ethylene propylene diene monomer (EPDM) ‑ Thermosetting, synthetic rubber used in single‑ply elastomeric sheet roof membranes.

Expansion joint ‑ A bituminous fiber strip used to separate blocks or units of concrete to allow free movement and prevent cracking due to expansion from temperature changes.

Felt ‑ Flexible sheet used in a roofing system produced by interlocking fibers with a binder or through a combination of mechanical work, moisture and heat.

Fishmouth ‑ Membrane defect consisting of an opening in the edge lap of a felt in a built‑up membrane; a consequence of an edge wrinkle.

Flagstone (flagging, flags) ‑ Flat stones from 1 to 4 inches thick, used for walks, steps and floors.

Flashing ‑ Connective devices that seal membranes at walls and other roof interruptions Base flashing form the upturned edges of the watertight membranes; cap flashing shield exposed edges and joints of the base flashing.

Gargoyle ‑ Water spout or decoration in the form of a grotesque human or animal figure which projects from a wall or water table of a building.

Glaze coat ‑ Thin protective coating of bitumin applied to the lower plies or top ply of a built‑up membrane when application of additional felts or the flood coat and aggregate surfacing is delayed.

Gravel ‑ Coarse granular aggregates from crushed rock, used as a protective surfacing or ballast on roof systems.

Gravel stop ‑ Flanged device, usually metallic, projecting above the roof level, design‑ to prevent loose aggregate, leaves or other waste from rolling or washing off the roof and providing a finished edge detail for the roof.

Grout - A mixture of cementitious material, cements or lime for example, and sufficient water to make a consistency that will flow without separation of ingredients.

Header ‑ A brick laid lengthwise along a wall and serving as a bond. A masonry unit laid flat with its largest dimension perpendicular to the face of the wall. It is generally used to tie two wythes of masonry together.

Hollow walls ‑ A wall built of solid masonry units laid in and so constructed as to provide an air space within the wall.

Lintel ‑ A horizontal structure member that supports a load over an opening such as a door or a window.

Loose‑laid roof system ‑ Design concept in which insulation boards and membrane are not anchored on the deck, but ballasted by loose aggregate or concrete pavers.

Masonry ‑ Stone, brick, concrete, hollow tile, concrete‑block, gypsum‑block or other similar building units or materials bonded together with mortar to form a wall, pier, buttress or similar mass.

Membrane ‑ Flexible or semi flexible roof covering ‑ the waterproofing component of the roof system.

Mineral‑surfaced sheet ‑ Asphalt saturated felt, coated on one or both sides and surfaced on the weather-exposed side with mineral granules.

Mortar ‑ A mixture of cementitious materials and aggregate, with or without the addition of plasticizers or other admixtures, reduced to a plastic state by the addition of water andsuitable for use to bind masonry units together.

Neoprene ‑ Synthetic rubber used in fluid‑or‑sheet applied elastomeric single‑ply membranes or flashing.

Parapet wall ‑ A dwarf, barrier or section of wall extending above the roof.

Pitch pocket ‑ Flanged, open‑bottomed metal container placed around a column or other roof penetrating element and filled with bitumin or plastic cement to seal the joint.

Pointing ‑ Mortar or the process of pushing mortar into a joint after a brick is laid.

Polyvinyl chloride (PVC) ‑ Thermoplastic polymer, formulated with a plasticizer, used as a single ply sheet membrane material or liquid coating.

Ponding ‑ water pool created by improper drainage or a depression in roofing surface which is lower than the drain.

Protected membrane roof (PMR) ‑ Roof assembly with insulation on top of the membrane instead of vice versa, as in the conventional roof assembly.

Reglet ‑ Horizontal groove in a wall or other vertical surface adjoining a roof surface for anchoring flashing.

Ridging ‑ Membrane defect characterized by upward displacement of the membrane, usually over insulation‑board joints.

Reinforced brick masonry (RBM) ‑ Brick masonry in which metal is embedded in such a manner that the two materials act together in resisting forces.

Reveal ‑ That portion of a jamb or recess that is visible from the face of the wall back to the frame placed between the jambs.

Roll roofing ‑ Coated felts, generally mineral‑surf aced, supplied in rolls and designed for use without field applied surfacing.

Scupper ‑ Channel through parapet, designed for peripheral drainage of the roof, usually as safety overflow system to limit accumulation of ponded rainwater caused by clogged drains.

Scuttle ‑ Curbed opening or hatch, with hinged or loose cover, providing access to the roof.

Shingling - Pattern formed by laying parallel felt rolls with lapped joints so that on longitudinal edge overlaps the longitudinal edge of one adjacent felt; whereas, the other longitudinal underpass the other adjacent felt. Shingling is the informal method of applying felts in a built‑up roofing membrane

Slag ‑ Porous aggregate used as built‑up bituminous membrane surfacing, comprising silicates and alumino-silicates of calcium and other bases, developed with iron in a blast furnace.

Smooth‑surfaced roof ‑ Built‑up roofing membrane surfaced with a layer of hot mopped asphalt or cold applied asphalt‑clay emulsion or asphalt cutback, or sometimes with unmopped inorganic felt.

Soffit ‑ The underside of an arch, floor, lintel, stair or other similar construction.

Soldier ‑ A brick laid on its edge so that its longest dimension is parallel to the vertical axis of the face of the wall.

Solid wall ‑ A wall built of solid masonry units, laid contiguously, with the spaces between the units filled completely with mortar. Also, walls built of solid concrete.

Spall ‑ A small fragment removed from the face of the stone, brick or other masonry material by a blow or by the action of the elements.

Splash block ‑ A small masonry block laid with the top close to the ground surface to receive roof drainage from downspouts and to carry it away from the building.

Stack (or chimney) - Any structure or part of a structure partly or wholly exposed to the atmosphere, which contains a flue or flues for the discharge of gases.

Stucco ‑ Most commonly refers to an outside plaster made with Portland cement as its base.

Tearoff ‑ Removing a failed roof system down to the skeletal structural deck.

Thermal shock ‑ Stress producing phenomenon resulting from sudden temperature change in a roof membrane when, for example, a rain shower follows brilliant, hot sunshine.

Through‑wall flashing ‑ Water‑resistant membrane or material assembly extending through a wall's horizontal cross‑section and designed to direct water flow through the wall to the exterior.

Veneer ‑ A facing masonry material attached, but not bonded, to the backing.

Vent ‑ Opening designed to convey water vapor or other gas from inside building or building component to the atmosphere.

Wall ties ‑ Strip of metal used for tying a facing veneer to the body of a wall.

Water table ‑ A slight projection of masonry or mid‑wall cornice, designed as an architectural decoration or, when slightly above the ground, as a protection against water.

1.	Solid Walla and Exterior Bricks.	1.	Copings
2.	Water Table or Mid-Wall Cornice.	12.	Interior Parapet
3.	Pealing.	13.	Exterior Parapet.
4.	Concrete Structures.	14.	Cap Rushing.
5.	Projecting Cornice.	15.	Base Flashing
6.	Lintels.	16.	Curtain Wall
7.	Elevator and Stair Bulkheads.	17.	Roofing Surface
S.	Wood oral Concrete Supports.	18.	Stone and Terra Cotta
9.	Pitch Pocket.	19.	Sills
10.	Stacks and Chimneys.	20.	Terrace.