| Roofing for Dummies |
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Roof Components
Flashing: Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof such as vent pipes, chimneys, adjoining walls, dormers and valleys. Galvanized metal flashing should be minimum 26-gauge Eaves: The horizontal, lower edge of a sloped roof Hip: The inclined external angle formed by the intersection of two sloping roof planes. Runs from the ridge to the eaves Soffit: The finished underside of the eaves Gable: The upper portion of a sidewall that comes to a triangular point at the ridge of a sloping roof Rake: The inclined edge of a sloped roof over a wall from the eave to the ridge Rafter: The supporting framing member immediately beneath the deck, sloping from the ridge to the wall plate Gutter: The trough that channels water from the eaves to the downspouts Vent: Any outlet for air that protrudes through the roof deck such as a pipe or stack. Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck Drip edge: A non-corrosive, non-staining material used along the eaves and rakes to allow water run-off to drip clear of underlying construction Deck: The surface installed over the supporting framing members to which the roofing is applied Roof Decks and SheathingA deck is the structural base for the roof system. The most common substrate of a steep-slope roof system is wood decks, such as plywood, planks and non-veneer decking. When replacing your current roof system you need to determine the integrity of your decking. Deteriorated areas should be cutout and replaced with new material that closely match's the existing thickness. The roofing deck should be smooth and sturdy with fasteners flush to the deck before the installation of the new roof system. If deck fasteners have backed out you should have new fasteners installed and the existing fasteners should be removed. When you replace damaged sheathing, your best results will be with the same material as the undamaged section of the roof. In no case may a different thickness be used. Thickness may not be built up satisfactorily with felt, shingles, or furring on rafters or trusses. Roof strength usually depends upon the same thickness. Under the multiple pressures of shortages of time, unskilled or unknown workers, materials, etc., it may be tempting to short cut or make do on repairs, but remember that a depreciated home and future expensive trouble can come with such a decision. You may receive insurance or other assistance now; later when problems reappear, you may bear those costs alone Different types of decks/sheathing1x6 T&G (Tongue and Groove) Boards Fasten to rafters with corrosion resistant, HD (hot-dipped) nails or staples at the rate of two 8d nails or two 1.75-inch staples per board on each rafter or truss. Plywood Sheathing Joints must be placed over rafters. Sheathing must continue over two or more spans. The face grain of the plywood must run across the roof rafters, parallel to the peak of the roof. Particle Board Sheathing This may be applied either parallel or perpendicular to rafters. Care must be taken to stagger applications so those four panel corners do not meet at one point. A minimum 1/16 inch gap between boards is required. Do not nail within 3/8-inch of the panel edge. Provide a half-inch gap from masonry (i.e. walls, chimneys). Take care to over cut holes for fitting around vents, plumbing, etc. Do not force fit. Fastenings should be with three 8d nails or four 1.75-inch staples per rafter crossed. Roof FlashingsFlashings are the most common place for a roof leak. The flashings at the penetrations and the perimeter must be inspected every year. When re-roofing your home, the proper installation of flashings and edge flashing details is one of the most important steps to a successful roof system. Wall cladding, such as metal siding, cedar shakes, stucco or EIFS wall systems cannot be removed easily and then reinstalled. This is one reason we suggest professional roofing contractors perform the work. When discussing the curb of your flashings you have to consider the curb height. One of the biggest concerns is with skylight or roof penetration installation is the lack of curb height. If a skylight or roof penetration does not allow for adequate flashing height, extending the height of the curb is recommended. On a steep-slope roof system, where a roof system is terminated at a wall, the use of appropriate base flashing and counterflashings, such as metal, cladding or siding, is necessary. If the height of the wall does not allow for proper installation of termination details, alternate flashing details will be required. For example, installation of a coping cap that acts as counterflashing may be an appropriate alternative detail The most common flashings are:Valley flashings Valleys need sturdy flashings because they receive more water then other parts of the roof system. One of the most common valley flashing is a W-shaped aluminum or galvanized metal which comes in 10-foot lengths and in 16 to 24 - inch widths (as the pitch of the roof gets lower, the wider the flashing it will require). On the majority of steep-slope roof systems, metal flashings are installed after the felt liner is in place and before the primary underlayment and finished roof system is installed. Flashings for drip edges and eaves A drip edge flashing keeps water from entering back under the roofing material along the eaves and rakes. Installing flashing on the drip edges and eaves is important factor to reduce damage from ice dams and snow build-ups. Chimney Flashings Usually, chimney flashing have several parts: solid base flashing along the bottom of low side, overlapping step along ascending sides and continuous saddle at the base on upper side of chimney. If the roof system is particularly steep, a cricket should be used on the backside of the chimney. Failure to provide for adequate flashing height at the design stage may result in serious problems that cannot be subsequently corrected. Many things affect the performance of the flashing system. They include the following: Compatibility between the base flashing and the membrane if they are of different materials. Difference in coefficient of thermal expansion between counterflashing and the wall or parapet to which it is secured, causing movement at the joints between one length of the flashing and the next. (This movement may be accommodated if only one end of the flashing is nailed. The remaining length is held with clips and the free end is secured with an S-lock joint. Failure to allow for free movement may result in failure of the fasteners or buckling of the flashing.) Failure of the reglet seals if caulking is not maintained or the counterflashing moves Independent movement between the adjacent wall and the roof deck (some slack must be left in the base flashing to accommodate such movement and allowance must be made for the counterflashing to follow these movements independently of the base flashing) Movement of the membrane; the base flashing will either be drawn with it, in which case its upper edge will be pulled downward and no longer protect as the designer intended, or it will tear Gutters/ Downspouts
One basic gutter is made from two boards nailed in a V shape. Such gutters were common over doorways in Norway . The foundations of these buildings were high enough that splash back did not reach the wood structure. Cobblestones were also placed around buildings to help reduce splash back and erosion. Today ... Rain gutters protect structures from ice and water damage. They help carry water off the roof and away from the house. Regarding the maintenance of your gutters, here are some things to know: Your gutter should be cleaned out at least ONCE a year. Dirt, leaves, tree limbs and other debris slowly decay guttering and prevent proper water drainage. If you are replacing your gutter, it's probably because you did not have it cleaned on a regular basis. Different types of guttersGutters can be made of five different materials: copper, wood, vinyl, galvanized metal, and aluminum. Aluminum: Custom cut; Cut on site by a professional contractor to the exact length desired; it is seamless. It is commonly available in white, brown, black, gold, and green. Copper: This comes in standard 10' lengths; joints are soldered. Galvanized: Comes in various baked enamel finishes and in lengths of 10' and 20'. It also comes 4" or 5" wide, rectangular or round and fluted. Vinyl: This is PVC (polyvinyl chloride). It is available in one width, 5", and in lengths of 10', 16', 21', and 32' and in white and brown. Wood: Usually made of fir, available at lumberyards in lengths up to 50'. It weighs five or six times as much as a metal gutter. Accessories and fittings: These include downspouts (also known as drains, or leaders), end tubes, leader hangers, spikes and ferrules (tubes through which gutter spikes fit) for hanging and leaf guards, which are grids that prevent leaves from entering the gutter. Gutters are hung by one of three ways, and your fittings will vary accordingly: with hangers attached to straps, with hangers attached to brackets, and with spikes that are driven through the ferrules and the gutter into the house. Tips for installationThe most common mistake in installing gutters is to assume the house is level and pitch the gutter off. Houses are rarely level. A level line must be established and the gutter pitched according to that for water to run down it properly. What is the purpose of downspouts?Downspouts are typically rectangular and of the same material as the gutter or scupper. Downspouts direct water away from your foundation! Proper water management around the foundation of your building or home can be very effective at keeping the water from entering your basement. Back fill any low areas, and slope the ground away from the foundation. The most serious problem with thunderstorms is downspouts that discharge the water next to the foundation! Remember your downspouts main purpose is to:
Homeowners and building owners are plagued with two major problems concerning their downspout extensions. The flimsy end is easily crushed and consequently plugged. Second, the downspout extension is not anchored, but hangs loose and is easily dislodged. When the downspout extension is bumped by a child or brushed by a dog, subjected to strong winds, etc., it falls off and becomes useless. All roof water will now be directed to the foundation, creating the potential for flooding. The gutter/downspout systems are designed to carry water away from the house, not to the foundation. Making sure that your downspout elbow/extension is always attached and free of debris will help unnecessary flooding Repair? Maintain? Replace?Repair
Maintain
ReplacementAdvantages
Disadvantages
Replacing Your RoofDoes your roof need to be replaced?
Here are a few ideas for your own conclusions:How old is your roof system? If your roof system is older then 20 years you might want to consider a new roof system rather than repairing your existing system. How many areas in your roof system leak? If the shingles on your roof are excessively curled or buckled they are probably starting to fail. Are you happy with the aesthetics of your roof system? What is your financial situation? Do you repair now and budget for a new roof system? Does your roof have two or more layers? (If more than two layers you might have to rep lace it because of State code.) Is your insulation level adequate? (Achieving its full R-Value ) Has your decking become rotted from long term leaking? (Replacing rotted decking gives the structure more strength.) If your roof is dark in color you may have algae. If algae is the only symptom your roof is exhibiting, it may be professionally cleaned to add years to the life of your roof system. If your roof system requires replacing and is only one layer you might consider a roof-over . This is an option, but it is not recommended. (Any visual flaws on the existing shingle roof will be exaggerated by roof-overs.) Re-roofing is the process of installing a new roof when a roofing system fails. Roofing system failure can be caused by a number of factors; including age, severe weather, poor workmanship, defective materials, improper specification of a roofing system, abuse and failure to maintain the roof with regular inspections. You should perform re-roofing only when all repair and restoration alternatives are deemed incapable of bringing a roof back to serviceable condition, or at your own discretion. If you are not able to make that decision on your own, it's time to contact a professional roofing contractor for advice regarding your roofing situation. Any roofing professional should be able to alert you to a number of considerations for your roofing needs. Protecting Your Investment
There is no such thing as a "maintenance-free" roof. However, there are roofs that require less maintenance than others. Even so, preventative maintenance greatly reduces the likelihood of leaks, damage and premature roof failures. On the ground, walk around your home with binoculars and inspect your roof for cracked, curled or missing shingles, as well as any excessive loss of the protective mineral granules. In your attic, take a flashlight and look at the underside of the roof deck and rafters for any stains or wet spots indicating water leaks. R Remove debris from gutters . Trim back any overhanging tree branches. Look for loose or damaged shingles. Check the open valley metal for rust. Prevent snow and ice dams from forming. Check the mortar on chimneys and parapet walls . Restoration involves the major repair of the roofing system, including the repair of all penetrations and re-surfacing of the roof to restore it to serviceable condition. The opportunity to perform restoration work normally exists two or three years prior to the end of a roof's life cycle and before significant damage can occur. As many as 10 years can be added to the useful life of the roof through restoration and typically the cost of restoration is one-half the cost of re-roofing. Millions of dollars a year are spent on replacing roofs that may have years of life left in them. Owners today need to recognize the importance of their investment and protect the home and its contents from damage, both in terms of the roofs cost and its replacement value.
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Ridge: The uppermost, horizontal external angle formed by the intersection of two sloping roof planes
First, a little history ...
First you must determine the history of your roof and the current problems. Some roofs have reached the end of their designed lives, it is now time to determine if you need to repair your current roof system or replace it with a new roof system.
Roof maintenance is an important part of overall home maintenance costs. Much like a heating system that needs to be regularly cleaned and "tuned" for peak efficiency, roofing systems must also be maintained for maximum protection from the elements. Saving money on maintenance is nearly always shortsighted. It typically costs more in the long run-as the cost of replacing major components and the inherent disruptions rapidly mount and become greater in scope.
e-caulk terminations and counter flashings ....
