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Advanced Building Systems
Roofing Repairs

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Anatomy of a Roof

The basic components and tasks of your roofing systems are as follows:

- The gutters collect and drain rainwater away from the house
- The downspouts are the exit spouts for water draining from the gutters
- The shingles are the individual overlapping elements of the roof
- The flashing is the metal or plastic weather stripping along the drip edges of eaves, vents, pipes, roof planes and the chimney
- The gutters collect and drain rainwater away from the house
- The downspouts are the exit spouts for water draining from the gutters
- The shingles are the individual overlapping elements of the roof
- The flashing is the metal or plastic weather stripping along the drip edges of eaves, vents, pipes, roof planes and the chimney

Invisible in this picture are the hidden materials:

- The decking is composed of wood boards nailed to the rafters of your house
- The felt is the underlying material between the shingles and the decking to help prevent leaks in case the shingles fail

Okay, assuming that rundown didnt put you into a coma, youre ready to gain some basic understanding about roofs and what causes them to silently wear out long before you expect them to.


  1. Describe the structure and materials used to construct a cold built-up roof (flat roof). 

 Built up roof is a generic term for a roof system that is literally built by adding layers. This is by far the oldest of the "modern methods" of roofing dating back to the early 1800's. Formerly, the built up roof membrane was the waterproofing agent and the bitumen was the adhesive. With the advent of synthetic fibers the rolls of the two principle elements have been reversed. Now, the bitumen is the waterproofing agent and the membrane is used to hold the bitumen in place.

The above picture represents a four ply built up roof. Built up roofs can be installed using different waterproofing materials including coal tar pitch, asphalt, cold application adhesive, and modified asphalt. All systems will utilize either base sheets, ply sheets (felts), or cap sheets in some combination.

The roof has a variety of surfacing options ranging including gravel, asphalt, coatings, or mineral surfaced. Different methods of surfacing aid in ultraviolet light protection, fire protection, or energy savings.

What is a Cold-Built-up Roof?

The typical New York City apartmenet building roof is called a COLD BUILT-UP Roof.  The build-up roof is applied over 3/4" roofing boards which are one inch thick.  These boards are place don top of the beams or framing above the top floor ceiling.

Step 1:  15# felt paper is nailed on to roofing board using galvanized roofing nails.  These are special nails with wide heads that can hold down paper without tearing it.   15# felt refers to asphalt saturated paper (also called waterproofing paper).  It is called 15# because every 100 square feet weighs 15 pounds. 

Step 2:  A second layer of 15# felt is applied with roofing cement (also known as tar or mastic).  These two layers provide a watertight roof.  But because it is so light, it would not last much longer than six months, so you apply a third layer.

Step 3:  A third layer is applied which makes the roof  wear well.  This layer could last 20-25 years depending on the quality of this third layer.  This layer is called a CAPSHEET and is applied with roofing cement.

The Capsheet comes in two qualities:

  1. 55# capsheet:  usually a smooth surface.  A 10 year guarantee can usually be obtained.
  2. 90# capsheet:  available with a mineral surface (small stones which add wearability).  A 20 year guarantee is usually available.


Built Up Roofing


Built-Up Roofing

Built-up Roofing

Most houses with flat or nearly-flat roofs are topped with built-up roofing, made from layers of asphalt-coated roofing felt. The top layer of asphalt on these roofs is usually covered with crushed rock or gravel, which serves to hold the roofing material down and protect it from damage by ultraviolet sunlight. Light-colored gravel also reflects the suns heat. (Such roofs are also known as tar-and-gravel roofs.) Built-up roofs can last from 10 to 20 years, depending on the severity of the weather.

Similar to built-up roofing is roofing made from a single layer of asphalt-impregnated material, called asphalt roll roofing. This is used more often on garages and outbuildings than on houses because of its relatively short life spanfrom 5 to 15 years. It is generally the least expensive roofing material available.

Built-up roofing is a flat or low pitched roof consisting of multiple layers of saturated felts, coated felts or fiberglass felts, mopped down with hot asphalt bitumen or cold tar bitumen and covered with an aggregate surface.  Built up roofs are generally used on commercial projects and some residential homes with flat areas.

Types of Shingles & Repairs

It's time to repair your roof after a damaging and harse winter and before the spring rains come. Read about more information on Ice Dams and how you can prevent them next winter.

This section categorizes popular types of roofing materials, their main characteristics and how to repair them. Shingles are now made in a variety of materials and colors that can dramatically alter a house's appearance.


Asphalt Shingles


Asphalt shingles are the most commonly used type of shingle. They're reinforced with fiber glass or paper and range in durability; typically 20 to 30 years.

Asphalt shingles usually have three sections or "tabs" per shingle and an overall length of 3'. Most have dabs of tar or roofing cement on front to hold down the shingle that will lay on top of it.


In most cases, a cupped or upturned shingle can be repaired by sticking it back down with roofing cement. Replace a shingle that's missing (or loose) by gently bending back the shingles above it. Remove any nails and remaining scrap pieces. Slide and nail the new shingle in place. Then glue down the raised shingles with roofing cement.


Laminated Shingles


Laminated shingles have gained a lot of popularity recently. Designed to add character, color and depth to the roof, laminated shingles are made of multiple, staggered layers of material (usually asphalt).

From afar, some types of laminated shingles give the look of an expensive slate or shake covered roof by incorporating angled or rounded tabs and shadow lines.


Laminated shingles are repaired much like three-tab asphalt shingles, but because laminated shingles are often thicker, they may require longer nails or staples to fasten them securely.




Slate (stone) shingles are highly durable (100+ years); but about 3 times heavier per square foot than asphalt. Slate is a bit more difficult to work with and less forgiving than asphalt shingles because they break easily. However, a slate roof can create a colorful, hand-crafted look that adds to the overall appearance of a house.

Cutting slate to size requires using a special pressure cutter or a pick-like hammer that splits the slate. Slate is easily damaged by walking on it, so you may want to contact a pro for repairs on areas that you can't reach from a ladder.


Replace a broken or missing slate shingle by working a nail ripper underneath the upper slate or cut the nailheads with a hacksaw blade. Test fit the new shingle and mark two nail holes on it at the gap created by the upper shingles.

Remove the new shingle, and from the back, punch new nail holes. Fit and nail the shingle in place. Slide a small piece of builder's felt under the upper shingles to cover the exposed nailheads.


Wood Shakes & Shingles


Shakes are typically made of cedar, spruce or treated pine. Hand-split shakes have a rough, textured look on the front and often smooth on the back. Wood shingles are machine sawn smooth on both sides.

Generally, cedar is the highest performing wood for making shakes. But, treated pine shakes also perform well. Shakes are brown or reddish in color when new, but usually fade in the first year to a gray color.

Wood shingles may be installed with only a slight gap between shingles. However, to allow for expansion, shakes should be spaced up to 1/4" from their neighbors.

Shakes normally last about 30 years before needing to be replaced and throughout that time individual shakes/shingles may shrink, warp, or splinter.


With a nail ripper, remove the nails holding the damaged shake. Remove any remaining scrap pieces, splitting them free with a pry bar and hammer if necessary. Fit the new shake and nail it in place at the gap created by the upper shakes. Dab some roofing cement on the exposed nailheads to prevent water penetration.

Types of Roofing

20 year shingles are sometimes referred to as 3 tab shingles. This style of shingle is cut to show 3 tabs per shingle.

3 tab shingles give a smooth look to the roof. If there is only one layer of 3 tab shingle on the roof it is possible to lay over the existing shingles with a new layer of 3 tab shingles.

However, the roof decking must be in good condition and be at least 1/2 inch thick or better because of the additional weight.

The down side of this technique of lay-over, is the expense to replace this roof when the time comes and the extremely fast deterioration of the lay over shingles. Heat and weather will cut in half the life span of the roof. Essentially, if this method is used, the next re-roofing job will cost twice as much and need to be replaced twice as fast.

Depending on the product, 3 tab shingles come in 20, 25 and 30 year limited warranties and a variety of colors. Click on the manufacturer icons above to visit their web sites for more information on the type of product you would prefer.

Here in the upper Gulf Coast area and the Houston metro area in particular, 20 year shingles will last only from 11 years to 14 years. This has been exacerbated more recently in the past few years due to drought conditions which reduce the life spans of these shingles. Shingles need a certain amount of moisture. Dry conditions cause the shingles to crack which leads to a faster deterioration of the roof.

3 tab shingles are the most inexpensive shingle to use. Prices range from $19.00 US to $ 30.00 US per square.

There are three bundles to a square and each bundle weighs between 75 to 90 pounds.

Be sure to check with your home owners association before you install new shingles because they not only may have restrictions on the color of shingle used but some associations do not allow the use of 3 tab shingles.

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Laminated shingles are more commonly referred to as Designer shingles provide a dimensional appearance to a roof.

These types of shingles come in a variety of colors, shades, cuts and warranties.

Designer shingles add value to a home. They are approved by most home owners associations.

Laminated or designer shingles are the most popular type of shingle today. They give the look of wood shingles at less cost. The average life span of a laminated 25 year shingle is approximately 16 to 20 years here in the Gulf Coast region.

Weight of these shingles vary from 80 to 100 pounds per bundle with three bundles per square.

Limited manufacturer warranties vary from 25 to 40 years. Click on the manufacturer icons above to visit their web sites for more information on the type of product you would prefer.

Most manufacturers also offer fungus guard to protect the beauty of the roof. With the high humidity and heat indexes in the Gulf Coast region and Houston Metro area, we always highly recommend a product with fungus guard.

The roof pitch, that is, the steepness of the roof will have a great deal to do with in determining if your roof can utilize a laminated shingle.

A steeper roof, starting with an 8/12 pitch requires a better grade of shingle in addition to using at least 30 pound felt.

It is highly recommended to never install a lay-over of laminated shingles over laminated shingles primarily because of the weight factor in addition to the fact that it creates a rougher lay down.

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Metal roofing products come in a variety of colors, shapes and density. The life span of a metal roof far outweighs its cost when compared to any other roofing material.

In the greater Houston Metro area, metal roofs are not approved by home owners associations although many will approve them if the have the look of wood shingles.

Standing seam metal roofs are very popular today with commercial buildings and rural residential homes.

The preferred gauge is 24 or 26.

Metal roofs are more durable than other types of roofing material and can withstand higher wind stress and suffer far less hail damage. They also reflect heat much better than asphalt shingles.

They do fade in color over time yet can be re-painted if treated properly at a minimum of expense.

Metal roofs are more expensive than asphalt shingles ... generally 3 to 4 times higher in comparison.

Aluminum or steel roofs give the home the look of wood shingles with the durability of metal. Most steel roofs will lower your insurance premiums by 7% to 10% depending on your insurance company.

There are a lot of choices and variables to consider in selecting a metal roof that is right for your home. Please contact us for a Free, No Obligation Consultation and Estimate.

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Flat roofs are very prominent on commercial buildings and a few residential homes.

Flat roofs are designed to carry the weight of standing water and provide a low slope drainage configuration.

Flat roofs are easily repaired and offer a great deal of durability.

There are basically three types of popular flat roof styles to choose from:

  • Tar and Gravel
  • Built Up
  • One Piece

Additionally, there are several types of processes to applying a flat roof. These types of roofing systems are best constructed by professional roofing contractors.

If you have a flat roof that needs repair you will be well advised to seek professional help. This is not a Do-It-Yourself project. A bucket full of liquid roofing cement is not a sure fix and will only add to your existing problem.

Flat roofs are specially designed to hold and drain water thus, changing the natural flow of water will cause further damage to your roof and the structure below it.

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Wood shingles offer an excellent option from both an appearance and an insulation viewpoint.

Wood breathes, thereby allowing heat to escape through the shingle. Attics with wood shingle roofs are normally cooler than other types of roofs with different materials.

Many sub-divisions do not allow wood shingle roofs because of their immense potential as a fire hazard.

If installed and treated properly, wood shingle roofs will have a greater life span than asphalt shingles, generally, 20 to 30 years.

Wood shingles offer an  appearance than like no other roofing product.

There are a number of new roofing products that give the look of wood such as steel shingles, aluminum shingles, fiberglass/asphalt shingles and the so-called 'mud flap" shingles.

As a cost savings measure, one might consider a lay-over wood roof shingle job. However, doing so will only provide a life span of 8 to 10 years due to the baking effect on the shingles from the sun.

Consequently, the next roofing job will require a complete stripping of all layers and re-decking which needless to say, is time consuming and costly.

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Not all roofs are the same. There are a lot of issues to consider when choosing a roof that is right for your home such as:

  • Cost and time of installation.
  • Is this going to be your final residence?
  • Do you plan to sell the home? If so, are you looking for a quick sale or do you want to get the highest price as possible for the house?
  • What are the Deed Restrictions? This may limit your choices.
  • Are you wanting to lower your energy costs?

Costs vary depending on materials used, the slope of the roof, the number of hips and valleys or dormers and gable ends, how many stories the home has, in general the overall complexity of the architectural dimensions of the home.

Not every roof needs to be replaced. Get the most from your roof. If it needs repair, repair it before costs increase. Keep debris cleaned out of roof valleys and rain gutters.

One square covers 100 square feet of surface area. There are three bundles to a square. 

Never exceed two layers of shingles on a roof. Roofs are not designed to handle the weight. Doing so will cause structural damage to rafters and ceiling joists.

Lighter colored roofs reflect more heat and darker colors absorb more heat. There is a very significant difference between a black roof and a white roof.

Black roofs in the Houston area are mainly for appearance, cost issues and don't show fungus. White roofs on the other hand will show more fungus and the material will break down faster. We typically recommend the earthtone colors such as light brown, grey, autumn blend or weatherwood.

Waves and dips on a roof are usually a sign of a rafter problem, bad decking or excessive weight on a roof.

It is highly recommended that you use a professional roofing contractor to install or repair a roof.

If you try to do it yourself, remember that it can be very dangerous work. additionally, it will also most likely void all manufacturers warranties on the product. If you make a mistake you have no recourse. 

  • Click here to view a larger image.

    Figure A

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    Figure B

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    Figure C

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    Figure D

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    Figure E

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    Figure F

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    Figure G

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    Figure H

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    Figure I

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    Figure J

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    Figure K

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    Figure L

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    A cordless roofing nailer is more costly than hammer and nails, but it will save you a lot of time, particularly on a bigger job.

    Q: An overhanging tree has been scraping my roof. How can I replace just a few shingles?

    A: (from DIY home improvement expert, Brad Staggs) If your roof has had some limited shingle damage (figure A), it is possible to replace just one shingle or course of shingles. Here are some tips and suggestions.

    Shingle Basics: Asphalt shingles are installed in overlapping courses, and are commonly constructed as three-tab strips. Each strip is nailed at regular intervals -- corresponding with the tabs -- along it's length (figure B). The nails are placed in a sealing strip that's made into the strip. Since the courses of installed shingles overlap (figure C), when removing a section of shingle you'll need to remove the nails in the course you'll be replacing as well as those in the course above it.


    Replacement shingles
    Pry bar
    Roofing nails
    Roofing cement
    Framing square with straight-edge
    Utility knife
    Cordless roofing nailer (optional)
    Safety glasses

    1. Begin by using a pry-bar to gently lift the shingle tabs and break the seal ( figure D) so that you can access the nails underneath. Asphalt shingles can be brittle and may break easily, so use caution as you lift the shingle tabs so that you don't damage the shingles in the course above.

    2. Once the tabs have been lifted clear, use a hammer and "cat's paw" nail-puller to slide under the head of the roofing nail (figure E) and carefully pry it up to remove it (figure F). Repeat this process for each nail in the section of shingle.

    3. With the nails removed, lift up and remove the damaged shingle (figure G).

    4. If the replacement strip is longer than the section you're replacing, you may need to cut off a portion of the strip. If you look closely, you'll notice that there are scored notches along the top edge of each shingle (figure H). You can use these scores as guides when you cut off a section of the shingle.

    5. Important: If you need to cut shingles, and you are working on your roof, you'll need to lay down a protective surface (e.g., some spare shingle strips) on the area of roof where you're working. This will prevent you from accidentally cutting into your existing (installed) shingles.

    6. To cut the excess length of shingle away, use the straight edge of a framing square, locking it against the scored tab for stability. Then make a straight cut using a utility knife (figure I). It may take two or three passes with the blade to cut all the way through.

      • Tip: Cutting through asphalt shingles is tough on cutting blades. Make certain you have plenty extra blades for your utility knife.

    7. To protect your roof sheathing, before you install the new shingle section, seal the holes where the nails have been removed using roof cement (figure J).

    8. Slide the new section of shingle in place (figure K), making sure it is even.

    9. Secure the new section with roofing nails (figure L) in roughly the same locations where the old nails were removed.

    HGTV's Complete Fix-It
    Author: HGTV
    Click HERE to order HGTV's Complete Fix-It book.


    What's so important About Flashing?

    Various exterior building elements, such as roofs, walls) foundations, windows, and doors, collectively form a protective "envelope" that shelters the interior of a building, protecting it from the ravages of the exterior environment. Water, among all the other possibilities, is the element that poses the greatest threat to a building. That is why so many building elements and details function either to direct water away from, or to keep water out of, buildings. A sound roof with an appropriate drainage system unquestionably constitutes the first line of defense against water penetration. But to be effective, a good roof must include items other than just the roofing material. One of them is flashing. The importance of flashing is often minimized, and its installation is sometimes ignored, especially in poor roofing installations. The purpose of this technical article is to explain flashing and clarify its indispensable role in keeping buildings watertight.

    What is flashing?

    Flashing is a construction detail used to seal and protects joints in a building from water penetration. The joints created by the intersection of the roof and roof mounted structures and projections, such as parapets, hatches, skylights, chimneys, vent stacks, or towers, are among the most vulnerable areas of roofing systems. They constantly expand and contract in response to changes in humidity and temperature. The greater the number of such projections, the greater the potential for serious leaks. Flashing is used at these intersections to keep rainwater from leaking into the building. It makes joints at these junctions watertight, while at the same time allowing the natural expansion and contraction of materials to continue. It operates on the principle that, in order to penetrate a joint, water must work itself upward against the force of gravity, or in the case of wind-driven rain, would have to follow a tortuous path during which the force of the wind would be dissipated.

    How Flashing Works

    Flashing is installed at intersecting roofs and parapets and walls. It typically consists of angled strips of corrosion- resistant metal that overlap in such a way as to discourage water entrapment. Flashing is composed of two parts-the base flashing and cap flashing (which is sometimes referred to as counter flashing).

    Base Flashing is the portion of the installation attached to the roof itself. It is "L-shaped" with one leg extended underneath the roofing material at least six inches, preferably more, and the other leg extending up the abutting vertical surface.

    In quality flashing installations, cylindrical roof-mounted structures, such as vent stacks, use base flashing composed of special sleeves that are an integral to the vent stack. However, since this type of flashing is expensive, a black ring of roofing compound is more often used. Roofing compound is unsightly and deforms easily with changes in temperature. Despite the expense, it is usually best to flash these structures properly with metal base flashing compatible with the rest of the roofing system.

    Cap Flashing is attached to the projection or wall with which the roof intersects and overlaps with the base flashing by at least six inches, so that water cannot penetrate this vulnerable joint. In masonry buildings, the cap flashing is imbedded in the "reglet"-the groove formed by the mortar Joint in a wall or parapet. In wooden buildings, flashing is usually nailed to the underlayment and its upper edge protected by clapboards, shingles, or whatever wall sheathing is being used on the building. When flashing is installed properly, the bottom edge of the cap flashing is usually turned by about 1/2 inch to stiffen the long strip of metal against the wind.

    Where cap flashing follows the slope of the roof, it is arranged in steps--with each step overlapping the one immediately below it. In slate, tile, or asphalt shingle roofs, the base flashing may also be woven into the courses of the roof sheathing in order to make a more effective watertight joint.

    The base and cap flashings are, or should be, independent of each other to allow for differential movement between the wall and roof structures. However, due to incorrect installation or damage from ice or vandalism, they occasionally bind. If openings or bends in the joints develop between the base and cap flashings, the joints will not move properly. The joints should be kept flexible, but tight.

    Saddles or Crickets

    Flashing at tall structures mounted on pitched roofs, such as chimneys, should employ a "cricket" or a "saddle." A cricket is a ridge installed between the roof slope and the protruding structure that deflects the flow of water around the protruding structure and keeps snow and dirt from collecting. If the cricket is being used in a small area, such as against a chimney, it is usually treated as a modified form of base flashing, extending under the adjacent roof sheathing in the same manner as normal base flashing, and turned up against the vertical surface and counter flashed. If a cricket is abutting a large vertical surface, such as the wall of a tower, and is exposed to view, it is usually treated as part of the roof structure and sheathed in the same manner as the roof.


    Valleys, which occur where different roof slopes intersect, are problem spots because the geometry of roof intersections often creates low spots, particularly at the eaves. Water can pond and ice can dam at these low spots, get underneath the adjacent roofing material, and cause severe damage. Most valleys are lined with a heavy gauge, corrosion- resistant metal, forming a type of flashing. This lining may or may not be visible depending on the type of roofing material used and the detailing of the roof intersections. If valley linings are not extended far enough beneath the adjacent roofing materials, leaks may occur when ice dams back up the valleys in the winter. This condition requires the eventual replacement of the valley lining.

    "Open valleys" are flashed by laying strips of sheet metal in the valley angle and lapping the adjacent roofing material over it. The width of the valley increases as it approaches the bottom to accommodate the increased flow of water.

    "Closed valleys" are only possible with slate, tile, or asphalt shingle roofs. They are far less common than open valleys, and the flashing required is far more complex. In closed valleys, the roof sheathing is brought tight to the valley line, and small pieces of flashing are arranged under each slate or tile. This flashing is invisible, but still absolutely essential to keep the joint watertight. Instead of individual pieces of flashing, long, overlapping strips of flashing are occasionally used in closed valleys. However, this mode of flashing tends to be less effective than using smaller, individual pieces of flashing for each course of slate or tile.


    Flashing may be either concealed or exposed. Flashing concealed within the construction of the building may be of either sheet metal or a waterproof membrane. Exposed flashing typically consists of pieces of sheet metal or impervious, flexible membrane material. Metal exposed flashing is usually of the following types: aluminum, copper, galvanized steel (painted), stainless steel, lead, terne-plate, or zinc alloy. Roofing felts are also used occasionally for flashings in certain types of roofs, such as asphalt shingle roofs or flat, built-up roofs.

    The choice of the appropriate material to use for flashing depends on several criteria. What is the most cost-effective material in a given situation? What is the most durable? Will the material being considered be visible to the observer? Is it historically appropriate to the building and the type of roof? Are the materials used for the flashing chemically compatible with the materials they will come in contact with? Copper, for instance, is the most traditional material used for flashing. However, it cannot be used with roofs composed of dissimilar metals due to "galvanic action," which sets up a chemical reaction between the copper and the iron in the roof sheathing. By the same token, it cannot be nailed to the roof deck or sheathing with iron nails.

    Exposed metal flashing affects the appearance of a building; its color, texture, and pattern should be considered. It should be durable, weather-resistant, and maintenance-free. It must not stain or be stained by adjacent materials or react chemically with them. Expansion joints should be provided to prevent deformation.

    Copper is the most popular material used for flashing. It is easily worked and shaped, and adjusts itself to temperature stresses. It requires no painting or other treatment, although it occasionally is painted to hasten the development of a natural green patina. Generally it is considered extremely durable. However, copper is susceptible to deterioration by "acid rain" and therefore deteriorates more rapidly these days than in the past. Coating copper with lead enhances its resistance to deterioration.

    Terne-plate (often referred to as "tin" although this is technically inaccurate) is also common. Terne-plate is composed of a base metal of iron or steel, which is coated with a mixture of lead and tin. Terne-plate has traditionally been painted and requires regular painting in order to prevent corrosion.

    Zinc, although more rarely used for flashing in this country, is extremely durable and generally requires little maintenance. As zinc oxidizes, it forms a protective coating, dark grey in color that is extremely resistant to weathering.

    Roofing felts are strips of felt impregnated with roofing compound. Although appropriate for certain types of built-up roofing, particularly on flat roofs, this is probably the least desirable material to use for flashing. Roofing compound expands and contracts in response to changes in temperature and deforms easily, often rendering the flashing useless within a year or two. Although usually cheaper to install initially than metal flashing, it constantly has to be renewed in order to remain effective, and thus any initial savings are usually nullified by the subsequent cost of constant replacement. In addition, roofing felts are not usually appropriate for use on historic buildings with visible roofs, particularly slate, tile, or standing seam metal roofs.

    Flashing Repairs

    Failure of the flashing system is usually a major cause of roof deterioration. Flashing should be carefully inspected for failure caused either by poor workmanship, thermal stress, or metal deterioration (both of the flashing material itself and of the fasteners). With many roofing materials, the replacement of flashing on an existing roof is a major operation--one that may require taking up large sections of the roof surface. Therefore the installation of top quality flashing material on a new or replaced roof should be a primary consideration. Remember, some roofing and flashing materials are not compatible.

    When repairing any metal flashing, avoid the temptation to use roofing compound (black "goop") to stop leaks. This often-used treatment is not a long-term repair and usually causes more damage to the basic material. Roofing compound becomes brittle and inflexible within one year of exposure to the weather, and whatever limited effectiveness it may have quickly disappears. More importantly the chemical interaction between the compound and the metal often accelerates deterioration and causes extensive corrosion. Coating valleys with roofing compound should also be avoided because roofing compound hides the condition of the valley lining and creates irregular surfaces that inhibit good drainage.

    Holes in copper flashing are best repaired with a soldered patch. Aluminum flashing is difficult to solder, so holes have to be covered by a "cold" patching methods. A number of commercial sealing products used for patching metal gutters, such as gutter tape, can be used for a "cold" patch. You can also make a temporary patch with sheet metal and flashing cement. Clean the metal with a wire brush or steel wool. Cut a sheet metal patch that overlaps the hole at least three inches on all sides. Coat the pack of the patch with flashing cement. Press the patch firmly into place--just hard enough so that the cement doesn't ooze onto the roof. Paint the patch to match the rest of the flashing. These patches are strictly temporary and should be inspected at least twice a year to make sure they are still holding. If cap flashing comes loose from the reglet, re-wedging and sealing the reglet should repair it. The reglet can be filled with mortar (preferred) or a high-quality sealant, such as urethane caulk.


    Any roofing system should be recognized as a membrane that is designed to be self-sustaining, but that can be easily damaged by intrusions such as pedestrian traffic or fallen tree branches. Generally damage from water or ice is less likely on a roof that has good flashing on the outside.


    Tamlyn base, or "L", flashings have multiple uses including: in roof valleys, to divert water away from shingles, and more to prevent water penetration. Manufactured from minimum .015 decimal mill-galvanized steel for top quality and transportation/installation/performance durability. Thinner decimal thickness fabrications also available where cost, not quality, is the overriding concern. Customized fabrications are available from 30 gauge to 12 gauge for special specification jobs; e.g., a government spec. of 5" x 12" x 18 gauge L flashing.





    2 x 4" x 10'



    3 x 3" x 10'



    3 x 5" x 10'



    4 x 4" x 10'



    4 x 5" x 10'



    4 x 6" x 10'



    5 x 5" x 10'



    6 x 6" x 10'



    7 x 7" x 10'



    3 x 11" x 10'







    Flashing:  the importance of following the specifications

    The importance of properly installing sheet metal flashing on any type of roof cannot be overstated.  While modern building materials may be waterproof, they cannot be expected to remain permanently resistant to moisture as the natural movement of buildings and the shrinkage of certain type of materials over the years may eventually lead to leaks. 

    Unwanted moisture can enter the buildings interior from any point on the roof.  Any area where there is a seam, joint, or connection left unprotected can cause damage to the interior, disintegration of mortar and masonry, and rusting of steel spandrels, lintels, etc.   

    Three common types of flashing frequently installed for protective purposes are counter flashing (or wall flashing), valley flashing, and gravel stops (or other edge metals). 

    Counter flashing are used where a roof joins a wall and serves the purpose of turning water from a wall on to the roof.  Counter flashing is used in conjunction with composition base flashing and must keep water from entering the building and allow for building movement.  It is strongly recommended that the base flashing be applied over a cant strip and be extended up the wall a minimum of 10 inches above the roof line and that a minimum of 4 inches is covered by the counter flashing. 

    Valley flashings are used to protect the valley formed on shingle, slate, or tile roofs.  The open portion of the valley should be a minimum of 5 inches.  The edges of the valley should be formed with a hook edge, cleated on 2 ft. centers, lapped 8 inches in the direction of the flow, and with the top of each section fastened with nails of material compatible with the flashing.  Copper (minimum of 16 oz.), or stainless steel  (minimum of 26 Ga.) is recommended material for valley flashing, but painted galvanized (minimum of 24 Ga.) can be used when the expected life of the roof is less than 15 years. 

    Gravel stops (and other edge metals) are used on the perimeter, rakes, and eaves of roof and serve the purpose directing water in a certain direction or away from the wall.  An edge metal should be a minimum of 4 inches by 4 inches, with a minimum of 4 laps, although 6 inches would be ideal.

    On some occasions, spec writers, general contractors, or architects fail to realize the importance of having flashing installed on their roofs, choosing instead to use felt or mastic in its place.  This will almost certainly lead to water damage and leaks, which could have been prevented through the proper installation of flashing.

    In the installation of flashing, if caulking is not used under the flashing before being attached to the roof as well as applying a bead along the seam after placing the flashing down, leaks still may occur as water may be able to leak under the flashing.

    Books on Roofing


    • An investment in siding, windows, doors, roofs and energy upgrades should increase the value of your home above their cost.

    • You can create a handy gutter scoop by cutting the bottom out of a half-gallon milk container.

    • After working with fiberglass insulation, wash your skin with soap and cold water -- warm water will open your pores and cause you to itch for days.

    • If your attic requires two layers of insulation, add a second layer of unfaced insulation on top of and perpendicular to the first.

    • If your home has a crawlspace, its floor should be lined with 4- or 6-millimeter-thick plastic sheeting to prevent moisture from entering your house.


    illustration OF SOME ROOF TERMS 


         Vent is also a Gable end or Gable roof or a type of dormer.         

         Rake end looks like vent side where the rake is also called a barge board.

         Eave is also the Fascia.

         Underlayment is roofing felt.   

    Reading List:

    For a complete updated list of Creative Homeowner books, click here .

    Home Book: The Ultimate Guide to Repairs, Improvements & Maintenance
    Editors of Creative Homeowner
    Hardcover -- 608 pages (September, 2000)
    (ISBN: 158011069X)

    Creative Homeowner roofing book:

    Quick Guide: Roofing
    David Toht
    Paperback -- 80 pages (May, 1995)
    (ISBN: 1880029375)

    Other Book Resources


    Ortho's All About Roofing and Siding Basics
    By Larry Johnston, ed., et al
    Paperback -- 96 pages (January 1, 2001)
    Ortho Books (ISBN: 0897214501)

    To order this title from, click here .

    Southern Living Roofing and Siding
    Paperback -- 128 pages (February 2000)
    Sunset Publishing Company (ISBN: 0376090790)

    To order this title from, click here .


    Popular Mechanics Weatherproofing and Insulation (Home How-To)
    By Albert Jackson
    Paperback -- 80 pages 2nd Edition (January 2002)
    Hearst Books (ISBN: 1588160785)

    To order this title from, click here .

    Insulating and Weatherproofing (Home Repair and Improvement -- updated series)
    By Time Life Books, ed.
    Hardcover Spiral Edition (December 1996)
    Time Life (ISBN: 0783539053)

    To order this title from, click here .

    Lowe's (Lowe's Companies, Inc.)
    PO Box 1000
    Mooresville, NC 28115
    Phone: 704-758-1000

    Clopay Garage Doors

    Clopay Corporation (A Griffon Company)
    Cincinnati, OH 45202

    Owens Corning
    Owens Corning World Headquarters
    Toledo, OH 43659
    Phone: 419-248-8000 / 6190
    Fax: 419-248-7506

    Creative Homeowner Information

    Creative Homeowner Press
    Upper Saddle, NJ 07458-0038
    Phone: 201-934-7100
    Fax: 201-934-8971