Information for Homeowners and Agents

Nothing is more frustrating than having negotiations between a buyer and a seller break down over a final work order which cannot be resolved between parties. One of the highest priced maintenance expenses a homeowner can face is the replacement of their roof. So, if a roof becomes an issue in negotiations, it is often a big issue. This flyer tries to explain some of the issues which homeowners and agents should be aware of when getting a house ready for the market, performing repairs to reach a minimum certification level required by lenders, and what a prospective buyer should be looking for when evaluating an older roof.


In Washington State, many lenders require that the roof on a home being financed will last at least 5 more years from the date of sale. While we would like to think that the lenders require certs to protect their clients, they may also be concerned with their own interests:

  • In the event of foreclosure and repossession, lenders do not want to have to replace the roof in order to sell the Home.
  • Lenders may not want their new clients (the buyer) to face any large unforeseen home improvement expenses in the first few years (presumably after making a substantial down payment), which might impede their ability to make their monthly payments on time.
  • From a financial perspective, the 5-year certification requirement may also create additional business for the lenders since the cost of replacing the roof is often included in the sale price of the home, resulting in more Volume.

While we are occasionally asked for two- or three-year certs, the norm is 5 years.

Home Inspections

When a roof is considered during a home inspection, most inspectors will give their general opinion on the condition of the roof. Although they are usually fairly accurate in their assessments, when a roof is past its mid-life, assessment can become more difficult, and many factors can come into play in determining the life expectancy of a roof. In those situations, most inspectors defer to roofing professionals to establish the condition and possible need for repairs or replacement.

What is a Roof Certification?

A roof certification is a professional roofer’s best estimate and opinion about the life expectancy of a roof.

Technically, a roofer is not able to determine absolutely if a roof has been installed properly. While the flashings may appear to have been installed correctly, the course pattern fine, and the condition of the shingles good, there is no way for example, that he can determine whether the correct number of nails have been used in each shingle or shake without damaging the roof.

Consequently, it is not reasonable to expect the roofer who certifies a roof to “Guarantee” someone else’s workmanship which he cannot evaluate conclusively. If he does this, he opens himself up to tremendous liability.

While inspecting the roof, the certifier should determine if there are any possible problems which should be addressed or fixed to ensure that the roof will last. The certifier should guarantee the roof against leaks and be prepared to repair any leaks during that 5-year period, free of charge. The contractor who certifies a roof should also take full responsibility for any work done by others as a result of his inspection and recommendation. He needs to put himself on the line. If the contractor doesn’t have anything to lose by certifying a roof, the cert is meaningless.

A roof certification should not involve any form of “risk management” where the roofer accepts liability based upon the size of the job and his potential liability. After an inspection and repairs have been completed, the roof either certifies or it doesn’t. Period. If the contractor feels uneasy about certifying a roof after repairs have been performed, then he needs to do additional repairs to get the roof to a level where he feels comfortable providing a certification. The certification is simply a piece of paper. Any substantial money spent on the roof should be allocated for repairs or replacement—not toward an insurance policy against future leaks. If you are paying more than $ 00 for a roof certification, you are paying too much.

The contractor asked to inspect a roof should do so with as much objectivity as possible. Siding with either the buyer or the seller will eventually create conflicts and will cause the contractor to lose credibility. He should simply call it like it is.

While many factors come into play during a roof inspection, the bottom line is whether the roof will last another 5 years without leaking. A composition roof installed by a homeowner might not have the proper or recommended pattern, but it might be perfectly adequate in terms of keeping the home waterproof for 5 more years.


Let’s face it, no one wants to have to replace a roof to sell a home. It almost doesn’t seem fair from a seller’s perspective since they will get no use of it. So, it is most often that a seller deals with this issue reluctantly. Here are some considerations to keep in mind:


  • Replacement cost – options might include recover, conversion from shake to comp, etc.
  • Cost to repair roof to certify for 5 years.
  • Weigh the benefits of the aesthetic value of reroofing.
  • Will it help sell the home?
  • Must I be concerned with covenants or a homeowner’s
  • association?
  • Should I convert to composition instead?
  • Should the material be Architectural vs. 3-tab?
  • Will the cert satisfy a buyer in this price range?
  • What would I want if I were buying this house?
  • If repair costs exceed 15-20% of the roof cost, perhaps that money would be better spent on a new roof — give the buyer the option to reroof with material of their choice and contribute cost of repairs accordingly.
  • If I reroof the house before sale, perhaps I limit the buyer’s ability to upgrade.
  • Perhaps I should include the cost of a new roof in the purchase price and negotiate later.
  • Sometimes it’s better to wait on repairing a roof to get a certification. For example, repairs on a shake roof might result in a patchwork of shakes which are different color shades. It will take time for these to weather. If repairs are done before the home goes on the market, a) It might detract from the overall look of the home, and b) it might serve as a red flag that the roof is or has been an Issue.


From a buyer’s perspective, if a home they are considering purchasing needs a new roof they will probably assume one or more of the following:

  1. The seller is waiting to see if the roof will be called outduring inspection.
  2. The seller does not have enough available funds to repair or replace the roof to make it presentable for sale.
  3. The seller has listed the home taking into account the fact that the roof might need to be repaired or replaced, and is willing to negotiate the issue when and if it comes up.
  4. The seller means “as is” and they really mean it!


  • You don’t want to deal with a roof issue for at least 5 years. Determine your comfort level in replacing a roof on this house. How big an expense are you looking at down the road?
  • How reliable is the roof certification which the seller is providing?
  • Weigh the lender requirements vs. your own needs. If you plan on adding a second story to the house, how does that affect the roof situation?
  • Realize that the seller may only be required to do minimal repairs or replacement. You may want to contribute to an upgrade in roofing material to match the house. A 3-tab roof might not look appropriate, but it is all that the seller is required to install.
  • Estimate how long you expect to live in the house. You do not want to get stuck having to replace the roof to sell the house. Consider giving yourself a buffer zone by upgrading to a long-lasting material to avoid this situation.
  • Even though a recover is acceptable now, it might be better in the long term to do a tear-off now and include the additional cost in financing.
  • Have reasonable expectations in line with the age of the home. Don’t expect a perfect roof.
  • If the seller cannot afford to pay for a new roof, then ask the roofer if he can be paid at closing. Or ask the agent and lender if they can do an escrow-holdback so the transaction can close, and the roof can be installed later. Then the roofer would be paid by escrow on completion. (This can be an important option when the weather is bad.) Escrow usually requires about 1 1/2 times the cost of the roof to be placed in escrow.

Formulas for Comparing Replacement and Repair Costs of Shake Roofs

A) Establish cost per year for roof:
Replacement cost /Average lifespan with variables to extend life = cost per year

Use the following variables in calculations:

    1. Pitch: steep roofs = add 2 years
    2. Roof has been treated at least once = add 3 years
    3. Heavy shakes installed = add 3 years
    4. Exposure is 8″ or less with 24″ shake = add 3 years
    5. Average roof life for a medium shake roof is 18 Years

B) To establish the value left in your roof
Multiply cost per year times number of remaining years to establish the dollar value left in the roof.


(A 15-year-old medium shake roof, steep)

  • Average lifespan (18 years) – Age of roof (15) = 3 years remaining life
  • Add for steepness: + 2 years
  • Expected remaining lifespan: 5 years

Cost for replacement = $10,000

$10,000/lifespan of roof (20 years)=$500/year annual Cost. Remaining lifespan (5 years) x yearly cost $500) = remaining value left in roof ($2500) This means there is about 25% of the life left in the roof. Use this for negotiation purposes. Perhaps a fair rule of thumb is to meet the buyer halfway on the roof and offer 50% value. The listing price might be adjusted accordingly before the house goes on the market so the seller can make adjustments when negotiating.

C) Establish cost per year for repairs

Cost of repairs/number of years the repairs are expected to add to roof life (beyond average) = cost per year for repairs

D) Repairs vs. Replacement

If the cost per year for repairs exceeds cost per year for replacement, might consider reroofing instead, taking into account the opportunity cost as described below.

E) Opportunity Cost

Money spent today on replacing your roof could be earning you interest via investments. Assuming a 7% return on investment, you can calculate the opportunity cost of replacing your roof as follows: .07 x (Replacement cost – repair costs) = the amount of money you are saving each year by repairing the roof instead of replacing

F) True Cost of Repairs vs. replacement

Cost per year for repairs – opportunity cost = true cost for repairs

What Lifespan to Expect from your Roof


One of the most difficult types of roofs to estimate the lifespan for is the cedar shake or shingle roof. In considering your client’s options, whether buyer or seller, keep in mind the following:

The average lifespan of a No. 1 medium split cedar shake (untreated with minimal maintenance) is about 17-18 years. Of the thousands of roofs we have replaced, most are 17 -18 years or older.

In the Northwest, it has been our experience that split cedar shakes tend to last longer than either Cedar Shingles or Tapersawn shakes—both of which are sawn on 2 sides.

Cedar Shake Roofs come in 2 thicknesses: Mediums (1/2″ 3/4″ thick at butt) and Heavies (3/4″-1 1/2″). The vast majority (over 90%) of shake roofs are mediums.

The quality of a shake is determined by several characteristics including the absence of knots, number of growth rings per inch which measures density and age, and the direction of grain. The minimum standard for roofing is defined as a Number 1 Grade Shake which must meet the strict ICBO requirements . These shakes must be free of
knots, have a minimum number of growth rings per inch, and a maximum of 20% flat grain. Over the years, this has been the most common shake used for reroofing.

In recent years, mills have offered a higher quality shake called a Premium Shake. These shakes are manufactured under strict guidelines and must be 100% “Vertical Grain” (also known as “Edge Grain”).

Finally, in the last decade, as the cost of cedar has risen, the relative expense of having a pressure treated shake has become more affordable. The treatment process results in a 30 year warranty and is known as a CCA treatment. (Similar to the Osmose and Wolmanized process for lumber.)

The standard exposure (the amount of shake you see on each course of roofing) for a cedar shake roof installed with 24″ shakes is 10 inches. When the exposure is reduced to 7 1/2 – 8″ per course, the roof now becomes a 3 ply roof (at any given spot there are three layers of cedar as opposed to two with a 10 inch exposure). A 3 ply roof will usually last several years longer than a 2 ply roof.

Steeper roofs last longer than low-pitched roofs because leaves, pine needles, moss and fungus are less inclined to retain moisture and cause deterioration of the shakes.

Although beautiful, cedar shake roofs do require periodic maintenance to help them last longer. Keeping debris such as pine needles, leaves and moss off the roof is essential. Cleaning with water or air is also suggested on roofs younger than 10 years. Preservatives also help extend the life of a roof substantially. We replaced a cedar shingle roof in Magnolia years ago which was 44 years old. The owner had treated it every year with his own special formula. At the time of replacement, the cedar was still in pretty good shape!

A single roof treatment should extend the life of a roof by several years.

While the quality of materials is significant in determining the duration of a roof’s life, the installation methods are equally important. While most roofs are installed according to generally acceptable practices, occasionally we will find a house built by a general contractor who hired sub-par roofers to save money. Those roofs sometimes exhibit excessive “shiners” (fasteners visible between shakes) and shakes which have been “butt stapled” to nail down warped boards to make the house more presentable for sale. Both problems can dramatically reduce the life of the roof.

In determining what repairs would be needed to get a shake roof to certify for 5 years, a roofer must consider the following:

  1. The condition of the wood—worn areas between shakes, missing shakes or ridge, exposed felt, rotted butts, excessive splitting, curled shakes.
  2. The number of shakes which need to be replaced. This is determined by walking the roof and counting the number of shakes and/or ridge which need to be repaired. The contractor should be conservative and include an additional percentage which will be needed as some shakes will be damaged during the repair process.
  3. Determine the efficacy of washing and treating the roof. While a treatment is always a good way to extend roof life, pressure washing can sometimes create more problems and damage the existing roof.


Unless a roof has obviously been installed improperly, it is seldom that we are asked to certify these kinds of roofs since they are usually guaranteed for 40 or 50 years.

Determining the lifespan of a low pitched roof is especially difficult. A typical lifespan for a 3-ply hot-tar and gravel or capsheet roof is about 20 years. A torch-down roof should last about 20 years as well The companies which manufacture torch-down typically offer a 10 or 12 year warranty. Hot tar roofs have no material warranty as they are “made” on the jobsite by the contractor using layers of fiberglass felt and hot asphalt. PVC and TPO roofs can also be expected to last 20 years.

The lifespan for both smooth hot-tar and torch down roofs can be extended substantially with a roof coating to protect the surface from the sun.

Typical signs that a flat roof is at the end of its life include blisters and air pockets, excessive cracks and “alligatoring,” areas where material has pulled away from the facia cap in the built-in gutters, and hairline cracks along seams and flashings.


The average lifespan of a composition shingle is usually a minimum of about 18 – 20 years.

In determining the life expectancy of a composition roof, the first consideration is the type of composition used. About thirty years ago, shingle manufacturers began converting the dies in their plants to manufacture a “metric” shingle which covered more area per shingle and therefore reduced the amount of labor involved per square. The 3-tab shingles lasted from 20-30 years. The Architectural shingles all have a minimum year warranty, making certification much more likely than 3-tab.

Certainteed Presidential TL, GAF Grand Canyon, Owens Corning Woodmoor, and Malarkey Windsor shingles are all considered “lifetime shingles” which can be expected to last at least 40-50 years. They are the heaviest and thickest shingles in this market.

When a composition shingle has been installed over an older roof, it will usually reduce the lifespan of the roof by 3-5 years. Consequently, recovers are usually done with heavier shingles which will compensate for lack of performance. (A 25 year shingle might be expected to last
20 years). Also, a common problem with older recovers includes nails backing up out of the shingles, poking through the top layer. This is usually due to improper nail length, although it is sometimes evident when a roof deck consists of shiplap or boards and the nails have not gripped correctly. If an older 3-tab roof is reroofed with a 3-tab metric shingle, the shingle courses will not match and will result in a “lumpy” look. To avoid this, recovers should be installed by either matching the courses (“sweet nailing”) or using a heavy Architectural shingle instead.

Proper ventilation on a composition roof is especially important and inadequate vents can result in a much shorter lifespan. Poor ventilation results in excessive movement of the roof deck which can loosen fasteners over time, and result in shingles curling and hairline cracks. In extreme cases the plywood roof deck can delaminate due to condensation problems and will need to be replaced. Adequate bathroom fan ventilation is also essential.


The most common problem areas on composition roofs involve the metal flashings around chimneys, skylights, roof-to-wall junctions, plumbing pipes, and vents. These can all be corrected rather easily if the roofing material is in good enough shape to warrant certification.

It is not uncommon to be asked to certify a composition roof which has been installed by the homeowner. Just because the job wasn’t done by a licensed professional roofer, it does not mean the roof is inadequate. While there are sometimes changes which must be made to flashings, etc, generally speaking in terms of certification it is irrelevant who installed the roof. Many homeowners are MORE meticulous than some roofers!

Jake Stout
Stout Roofing, LLC

17712 134th Ave NE, Woodinville, WA 98072

Toll Free: 888-280-0060
Eastside: 425-643-0888

Background and Experience

  • B.A. Environmental Studies & Geography, UW 1978
  • Master’s in Communication in Digital Media, UW 2013
  • 40 years operating Stout Roofing serving over 12,000 clients

Pioneered roof recycling in Washington State. First to perform lab burn tests on roofing material to determine use as fuel in co-generation facilities (Simson Tacoma Kraft, Scott Paper). Worked with Dept. of Transportation and Clean Washington to initiate the recycling of composition shingles into asphalt road base. Founded Roof Recyclers which accounted for over 3% of all recycled material in King County.

Owned and operated two shake mills which manufactured cedar shakes and shingles—Snohomish, WA and Nanaimo, BC. Negotiated salvage timber rights with Weyerhaeuser, Summit Timber, TAT USA, MacMillan Bloedel, and others. Responsible for helicopter logging, selection of cedar, production, shipping and ultimately installation on roofs.

First to promote environmentally safe roof preservative treatments in Seattle.

Past residential clients include:

  • Chairman of Weyerhaeuser, Publisher of the Seattle Times,
  • Chairman of Continental Airlines, co-founder of Microsoft,
  • President of Washington Roundtable, President Seattle
  • Rotary Club, Quarterback for Houston Oilers,
  • anchorperson for KOMO News, and the President of the
  • Washington Teacher’s Association, among others.


Inspection/Certifications: $450
(includes up to 1/2 hour of on-the-spot repairs if needed to certify) Estimates for repairs or reroofing: free


Over the years, manufacturers have experimented with new types of roofing materials with mixed results. Some materials have had problems/failures which resulted in class-action suits.

Manufactured by Masonite
Class action lawsuits pages for Woodruf Roofing
(Masonite), Omni Wood Siding (Masonite), and Masonite Hardboard Siding.

Manufactured by American Cemwood
American Cemwood Roofing Settlement

Produced by Recon, Inc. 1-541-349-1523
FireFree® Class Action Settlement website.

Resources and More Information

These companies offer a broad selection of roofing products available in the Puget Sound area. Homeowners and buyers can choose from a wide variety of shingles and colors.

CertainTeed Corporation
CertainTeed offers roofing products for almost any need including Landmark and Presidential shingles.

Owens Corning
Roof shingles & MiraVista shake, slate, copper and metal roofing are part of a complete Roofing System for building & remodeling.

GAF Materials Corporation
Founded in 1886, GAF Materials Corporation is one of the oldest manufacturers of commercial and residential roofing products in America.

PABCO Roofing Products
Pabco Roofing Products is one of the Northwest’s oldest manufacturers of composition shingles.

Monier Roof Tiles
Welcome to MonierLifetile, Americas #1 selling roof tile, and the nations oldest and largest roof tile manufacturer.

Malarkey Roofing Company
Welcome to Malarkey Roofing’s Web Site! Your local Northwest Manufacturer.

Champion Metal of Washington, Inc.
Champion Metal of Washington, Inc. presents SNAP-LOC Steel Roofing Panels