The purpose of roofing material is to form a weatherproof surface, which prevents water or snow from entering the house. The materials used must be both waterproof and wind-resistant to afford effective protection of the dwelling.
Roofing materials have various life expectancies. Life expectancy is dependent upon building orientation to the sun and roof slope. The manufacturer provides a written warranty for each particular product, which delineates what, is and is not covered. Although the sun is the major damaging force, wind and moisture also causes deterioration.
There are several types of roofing material used including asphalt, glass fiber, asbestos, wood tile and slate. The normal measurement of shingling material is the “square” which represents enough material to cover 100 square feet of roof area. Most manmade roofing materials are sold on the basis of longevity rather than weight and can be divided into several categories: organic vs. fiberglass, standard, laminated and specialty.
Wood shakes, slate, and tile roofs each have a specific method of installation recommended by manufacturer.
Shingle underlayment must be applied directly to roof boards. The purpose for this underlayment is as a secondary barrier to your roof covering.
Roofs or flashing should not leak under normally anticipated conditions. However, occasionally leakage may result from severe weather conditions, such as ice buildup, high winds, or driving rain.
During extreme weather conditions, water may overflow the gutters. Homeowners should check gutters and downspouts regularly to prevent leaf build-up in fall and snow and ice dams in the winter, which can cause water to backup under shingle and cause leaks.
Storm damage to properly installed roofing is the owner’s responsibility.
It must be noted that in the case of a repair to a roof, every effort should be made by the builder to match material and color as closely as possible. The homeowner must expect color variations.
Performance Standard – Roof should not leak. See homeowner’s maintenance responsibility below. The integrity of the roof is dependent upon the performance of many trades. Roof application, sheet metal work, siding application, masonry, carpentry and plumbing can all have an effect on the ultimate performance of the roof system.
Builder Repair Responsibility – When a leak appears, builder should make an inspection to assure that the proper trade makes the repair, except when the leakage is a homeowner’s maintenance responsibility.
Homeowner Maintenance Responsibility – Excessive ice or snow buildup with alternate freezing and thawing can create a condition causing leakage, which is a homeowner maintenance responsibility. Owner can correct this by preventing leaf buildup gutters and removal of excess snow and ice. In severe cases, a gutter heating cable can be used. On some occasions, a driving rain with high wind velocity can produce a temporary leak. Owner can also contract builder as to alternative suggestions on how to correct.
Craig’s Comments: Leaking near the eve from ice and snow build up is commonly refered to as ice damming. This is often caused by inadequate insulation near the eves, or leakage of warm house air into the attic. In either case, it is something that should be addressed by the builder. Some builders use a self-adhering roll material such as Ice and Water Shield along the eve to help prevent water entry during ice damming.
2. Common Defect or Problem – Chimney or chimney flashing leaks.
Performance Standard – Chimney or chimney flashing should not leak.
Builder Repair Responsibility – Builder to check and repair chimney flashing. On particularly persistent and severe leaks, the builder may find it necessary to modify, or install a saddle between the roof and the chimney to divert roof water run off from the chimney. If the flashing is not the cause of the leak, owner is responsible to seal masonry.
Craig’s Comments: If you have to seal the masonry to stop a chimney leak, something is wrong. Flashing may be missing or installed incorrectly. Quite often, the flashing on the outside of the chimney looks OK, but it is the flashing (or lack there of) behind the brickwork that is the problem. Water will move through brick, and needs to be directed away from the house somehow. Build the house as if the brick does not exist. If it won’t leak that way, your brick chimney will not be a problem. Sealing is a bad idea.
Performance Standard – Shingles should not blow off during the warranty period except under storm conditions. It should be noted that seal down shingles require heat from the sun to cause their sealing, so that some warm weather is required to affect the full seal.
Builder Repair Responsibility – Builder to repair shingles that have blown off if not due to winds in excess of basic wind speeds (see codes). In a repair situation, the owner is cautioned that a color mismatch in shingles may occur.
Craig’s Comments: Manufacturers of most 3-tab shingles specify 4 fasteners per shingle, though sometimes roofers use only three. In some high wind locations, like along the coast, the spec’s call for even more fasteners. Specify in your contract that the shingles be installed per manufacturer specifications.
4. Common Defect or Problem – Shingle color mismatch.
Performance Standard – Color variations in roofing materials are normal and acceptable and are not covered under any warranty. Angle of the sun, granule placement, pitch of the roof, any many variables can all have an effect on the appearance of the roof.
Builder Repair Responsibility – None.
Craig’s Comments: Sometimes the color mismatch is really an installation pattern problem. Due to the color variations between packs, manufacturers often specify how to install the shingles to minimize the apparent mismatch. Specify that the shingles be installed according to manufacturere’s specifications.
7. Common Defect or Problem – Moss and fungus growth on wood shake shingles.
Performance Standard – Under some conditions, moss and fungus tends to grow on cedar shake shingles.
Builder Repair Responsibility – None. Homeowners may wish to pursue remedies on the market that can be applied to shingles to prevent or retard these conditions.
Craig’s Comments: Wood shingles are difficult to use in our humid climate. The trick is to keep them as dry as possible and dry them as fast as possible. Wood shakes and shingles should be installed over furring strips or a material such as Cedar Breather so that the shingles can dry to the back side as well.
Performance Standard – Under driving rains or snow conditions, vents may leak. Vents are a necessary and integral part of a building. Anything that lets air out can, under certain circumstance, let snow or rain back in.
Builder Repair Responsibility – This is a normal, temporary condition, which should require no repair.
Craig’s Comments: Don’t mistake condensation within the vent or a leak around the vent for a rain leak. Those problems are not normal, and should be corrected. Some roof vents allow less wind-blown rain than others. Roof vents, in my opinion, are not a necessary part of a well-performing attic. So my recommendation is to leave them out.
10. Common Defect or Problem – Ridges of roof decking showing through roof.
Performance StandardIf the ridge or depression effect exceeds 3/8″ and cannot be corrected from below, the ridge must be corrected. The ridge measurements should be made by measuring the gap created when a 6″ straight edge is placed tightly 3″ on one side of the defect and the gap measured between the roof and the straight edge of the other end. Fiberglass shingles will magnify and mirror any uneveness of the roof decking below.
Builder Repair ResponsibilityBuilder to meet Performance Standard
Craig’s Comments:Roof clips are commonly used between rafters to support the edge of the decking. The end of the decking should fall on a rafter. Excess moisture can cause decking to buckle.
11. Common Defect or Problem – Chimney flashing leaks.
Performance Standard – Chimney flashing should not leak. However, some masonry is porous, allowing moisture/dampness to seep in under certain conditions
Builder Repair Responsibility – Builder to check and repair chimney flashing. If the flashing is not the cause of the leak, owner is responsible to seal masonry. On particularly persistent and severe leaks, the builder may find it necessary to modify, or install a saddle between the roof and the chimney to divert roof water run off from the chimney.
Craig’s Comments: See #2 in this section. Flahsing should be cut into the chimney rather than caulked to the surface. A saddle is always a good idea, to prevent the accumulation of leaves and debris from piling up behind the chimney.
13. Common Defect or Problem – Gutters and downspouts leak.
Performance Standard – Gutters and downspouts should not leak, but may overflow during heavy rains. It
shall be the owner’s responsibility to keep gutters and downspouts free of leaves and debris which could cause excessive overflow.
Builder Repair Responsibility – Builder to repair so gutters and downspouts do not leak
14. Common Defect or Problem – Water stands in gutters.
Performance Standard – A water level not in excess of 1″ depth in any gutter section after the rain ceases when unobstructed by debris is acceptable. Industry practices is to install gutter approximately level without pitch. Consequently, it is entirely possible that small amounts of water will stand in certain sections of the gutter after a rain.
Builder Repair Responsibility – Builder shall correct when water level is in excess of ½” in depth.
Craig’s Comments: Gutters should drain completely. Slope them slightly, or add downspouts. Keep the mosquitos from growing in your gutters.