The first step is to understand that the vast majority of our residential roofs are designed with a pitch because they are actually not waterproof systems. Roof pitch, which defines how steeply the roof rises in elevation, allows the roof to shed water and dictates what types of materials are appropriate and how they should be installed. Low pitch roofs require different installation techniques while very low to no pitch roofs will need waterproof materials. Low pitch roofs on manufactured homes for example should be installed much differently than conventionally pitched stick built homes. These low pitch application guidelines are available through the Washington State Department of Labor and Industries.
The next question is whether to re-roof or recover. Re-roofing means that all the existing layers of roofing material will be torn off and the roofing material replaced. Re-covering means that a second or possibly third layer will be installed over the original roof surface. Because of load bearing considerations, generally, no more than two layers of composition roofing are allowed on stick built homes and never more than one on a manufactured home. In cases where home inspections reveal multiple layers of roofing material, the nails are rarely secured into the wood decking making the roofing material very susceptible to being blown off in high winds.
Financially, the initial cost of re-covering is less expensive as there are no appreciable waste disposal fees, but it is a trade off over the long haul as life expectancy can be reduced 20% or more depending on the condition of the roofing beneath and who you speak to.
Now it is time to decide on what product to use. Start by checking any neighborhood CCR’s as there may be stipulations or restrictions. Next, think about your plans for the residence. If you’re intending to sell in a couple years, it probably makes no sense to pay top dollar for a higher end product unless that is the norm for your neighborhood. However, if you plan long term occupancy, paying more for something better may ultimately be more cost effective.
Regardless, if you are thinking of selling anytime in the near future, it would be wise to establish a relationship with a professional Realtor and get their feedback on any home improvements before you put your cash on the line.
While there are a myriad of product choices, most homes here have traditional asphalt composition or fiberglass shingles which are basically categorized into three tab shingles or laminated shingles. Warranties will range from a minimum of 20 years all the way to 50 years. Cedar shake and shingle is still available, but is very costly. Depending on your circumstances, metal or concrete tile may be desirable, however, you can expect higher prices than with composition roofing. There may also be weight considerations to keep in mind with tile. Based on the standard unit of measurement for roofing, a square or 10ft X 10ft, the typical weight of composition roofing ranges from 200 to 340lbs per square while standard concrete tile may range from 900 to 1050lbs per square. The manufacturer of one of the most widely used tiles in this area, Monier, recommends evaluation by a structural engineer before re-roofing with standard weight tiles to ensure no structural reinforcement is necessary.
As we face the heat of summer, consider the color of your roof. Darker colors not only tend to wear faster, but definitely make for hotter attics and often hotter houses. Neutral colors such as light grays and browns may also be more appealing to future potential buyers. Finally, improving roof ventilation to meet or exceed current standards is not only required by code during a re-roof, but can also work wonders to keep your home more comfortable.
Larry owns and operates Cameo Home Inspection Services and teaches home inspection at Kaplan Technical College. He can be reached at 360-459-1632