When to replace your roof

If your roof is close to 20 years old, replacing the entire roof covering is the best way to go. Every house will, at some point, need a roof replacement. A few signs that the roof needs replaced are:

  • Broken and missing shingles
  •  Asphalt shingles with little to no stones remaining
  • Curling or cracked shingles
  • Visible damage from severe weather conditions
  • The existing roof is 15+ years old
  • The home’s interior ceilings/walls have water marks due to serious roof leaks
  • The existing roof was installed incorrectly


Unfortunately, if your roof is the last item listed above, we have seen conditions that required immediate replacement – a major and unnecessary homeowner cost.  Always confirm your roofing contractor has experience, uses high quality materials and has adequate insurance in the event your roof is incorrectly installed.

If you plan on doing renovations within your home and need a roof replacement, replace the roof first. Nothing worse than creating a beautiful inner space with new paint, fixtures and flooring and having water damage due to an aged roof or damaged roof conditions!  Most remodeling projects are rendered useless if the roof is in no condition to protect the home’s interior/exterior remodeling. Replacing your old roof with a new one guarantees proper sealing, up- to- date flashing and underlayment while also guaranteeing you security for  structural and cosmetic integrity of your home.

When not to replace your roof

There are very few instances when you should NOT replace your roof. Such as:

  • If your roof is in good condition with years left on its lifespan
  • If you plan on doing a complete strip and rebuild it project in which case you would want to get the roof replaced at the correct time during the remodeling

When to use spot repair

Spot repair is when you only need to repair a small portion of your roof because it is in poor condition or has been damaged by severe weather conditions. If your roof still has a lot of life to it and only has a small area that needs replaced due to weather damage, obviously a spot repair is better than replacing the whole roof.

What causes the most damage to roofs?

During the summer, the sun has been found to take more years off your roof’s life than any other factor. UV radiation emitted by the sun cooks your roof’s shingles and eventually causes them to become fragile and break off. During the life of your roof, severe weather commonly damages your roof and creates weak spots which are mostly found along edges where your roof meets plumbing vents, walls or chimneys.

Of course there’s always other extenuating circumstances in which your roof can have severe damage done, much like what this little critter caused!

Roofing materials

75% of residential housing in the United States use Asphalt shingles, although your choice of roofing material may vary depending on where you live, what you can afford and what truly appeals to you. There are only a few different types of materials that are commonly used for roofing, such as; Asphalt Shingles, Wood Shakes, Slate, Metal, Clay and Concrete roofing.

Asphalt Shingles-

Asphalt Shingles have been the most commonly used roofing material for about the past hundred years. They are well known for being affordably priced, having longevity, easy maintenance, and being a very reliable material. Installation for asphalt shingles takes less time than other materials, thereby costing less for consumers in labor hours.  The life of average grade asphalt shingles last approximately 20 years, higher end are warranted 50 years or “lifetime”.

The cost for asphalt shingles using an example 1200 square feet (12 squares) runs between $700 to $2200, depending on quality and design (this does not include flashing, ice-water shield and other materials).  We try to provide our customers with higher end asphalt shingles with dimensional architectural designs and high definition colors, which create a high-end look to their homes.  For a fun and educational website on roofing materials, go to http://www.gaf.com and peruse their roofing systems.  You’ll notice GAF is the forerunner in asphalt shingle designs for residential homes and extends a life-time warranty with their materials if installed properly. GAF is our primary supplier, and our principle choice in roofing materials due to their quality, integrity, warranty and affordability.

High Def Asphalt (Wood Shake Look) “Camelot” by GAF

The installation cost for asphalt shingles is less than other materials due to the ease of which these products are installed.  The sample 1200 square foot asphalt shingle roof costs between $1000 to $3000, again depending on thickness and angles of the shingles.  If you can remember the higher the quality shingle, the higher cost or more time consumed for installation.

We commonly advise our clients to go with a higher end, architecturally designed, visually pleasing asphalt shingle roof for the minimal price difference.

Compare the looks of standard shingles versus, say a GAF Camelot or Grand Slate or Timberline HD (high definition) compared to the standard 3 tab shingles, and you’ll agree the tremendous value for your home is well worth the nominal cost increase.

In a nutshell, a 1200 square foot roof that’s 30 years old, requires some repairs, weather shields, sheathing, new shingles, some plywood decking replaced, plus new drip edges, and the cost of disposal of existing roof would cost the average of $4500-7500.

Wood Shakes-

Wood shakes have been around much longer than traditional Asphalt Shingles and are usually made from Cedar wood. They often use Cedar due to its natural resistance to decay/ rot when applied to an exterior roof. A properly installed Shake roof can last up to 30 years when properly maintained, however a Shake roof that isn’t cared for or is improperly installed will likely need to be replaced in 15- 20 years. Shake roofs are also available in Hand Split Shakes which create a rougher appearance compared to machine cut wood shingles which have a smoother look about them.

wood shakes

Wood Shakes

The cost of traditional wood shakes for a 1200 square foot roof are approximately $4500-$6300,  which is about 4 ½ times the cost of asphalt shingles.  Installation costs are similar to asphalt shingle.  However, the tear off and disposal of the original wood shake roofs can be more time consuming due to the removal of often-rusted, aged nails in the substructure, therefore costing more to get rid of the old roof.

Slate Roofing-

Slate roofing is a very attractive, high- end material which requires additional substructures to support their heavy weight on the roof. Although Slate is one of the longer lasting types of roofing materials, it can be expensive to put on your home. At the same rate, if you are going to stay in your home for many years, installing a Slate roof is a smart investment. American Slate roofs are a durable, natural material having a life expectancy of 75- 200 years!

The cost of slate roofing is considerably more than asphalt and wood shake.  Using a 1200 square roof standard (same as above for comparison), slate runs between $7100 to $10,000.  One also must consider the integrity of the substructure, which could be additional costs. The foundation framing must be capable of supporting the increased weight of slate (stone) and costs more than conventional framing for lighter materials, such as asphalt.

slate and copper

Slate and Copper

However, the beauty of a slate roof has none to compare – the patterns, colors of natural stone and cuts are not reproduced elsewhere and are often featured in architecturally unique housing designs. Installation of slate roofs is a specialty trade for skilled craftsmen and installation costs run about half the cost of the slate material.        


Slate Color Variations

The total cost for a slate roof can span quite a range due to quality and availability of slate materials, substructure repairs and/or replacements and labor costs (slate is heavy).  A 1200 square foot slate roof will cost anywhere from $11,000 to $16,000.  Despite the cost for a slate roof, there’s no industry comparison for beauty, warmth and durability –  which is why is why so many people have installed slate roofs.  Slate roofs also require little to no maintenance, another bonus feature of a truly natural product!

Metal Roofing-

Metal roofs add an elegant feel to your home and are often times affordable depending on your choice of metal.

metal roof

Metal Roof

Three types of      commonly seen metal roofs are Copper, Aluminum, and Steel. Metal roofing quickly dissipates heat which makes it energy– efficient compared to other roofing materials. Some metal roofs last up to 50 years! and require little to no maintenance, except when nearby mature trees aren’t properly pruned, branches or limbs fall and dent the metal.  Metal roofs are also energy efficient sustainable building materials for environmentally conscientious homeowners.

Metal roofs are available in either shingles, panels or tiles.  Of course, panels are the least expensive to install since they cover a larger area in shorter time.  Aluminum roofs withstand corrosion better than steel in coastal regions and steel requires painting maintenance over time.  Also, steel is heavier than aluminum and requires reinforced substructure materials compared to aluminum.  On an existing home, choosing aluminum in place of steel is  overall a less expensive installation.

However, aluminum is a softer textured material and more susceptible to dents and dings; it often warps or sags when installed on more vertical pitches due to it’s softer composition.  In addition, steel withstands fire and heat better than aluminum.  So the pros and cons of steel to aluminum are more a personal choice, the consumer’s preference of importance in features.

When it comes to copper roofs, you are selecting the most sophisticated metal roof material: not only do you have a genuinely fine quality material that is 100% recyclable and environmentally friendly, copper products are tough, durable and with proper care and maintenance, easily last 50 years or more.  They are surprisingly lightweight and

copper roof

Copper Roof

easy to install, and although more expensive than aluminum or steel, copper has been used for roofs for hundreds of years.

Aluminum and steel roofs are similar in cost: steel runs about $5500 to $7700 for 1200 square feet while aluminum is $6300 to $10,000.  Installation is the same, which runs between $1200 to $3000; a total estimated cost for either of these roofs would safely be in the $7000 to $13,000 range.

Copper roof materials are higher due to the durability and quality of the metal, with $13,500 to $16,000 costs on a 1200 square foot roof, plus installation of $2500 to $5700.  Copper roofing is commonly installed as a paneled seamed roof, which requires special equipment and is not advisable to be done by laypeople. 

There ARE quirks to having a metal roof: I remember as a young child hearing my sleepy-eyed Grandfather outside yelling at noisy squirrels who were carrying on, playing with acorns on top the metal farmhouse roof at 5 am!

When deciding which roofing material you want for your home, weigh the pros and cons of each material before making your final decision.  Consider the durability, the longevity you require for your investment, the appearance you desire to capture on the exterior of your home.   Also don’t forget to see how much your roof pitch is, which is the angle of your roof: this can determine the appropriate types of materials for your roof (i.e. shorter pitched roof – flatter – would not be conducive to wood shakes…. which would quickly deteriorate with sun/weather exposure and little moisture run off).  Take into consideration the existing substructure of your roof, it’s ability to support heavier materials such a stone slate or clay tile.

Roof Replacement Cost

Old wood shakes

Old Wood Shakes

The cost to replace an entire home’s roof(s) can vary drastically depending on the roofing materials, the pitch of your roof, the amount of area being replaced, the contractor installing the materials, et cetera. Overall, the cost to replace the roof of an average American home with inexpensive Asphalt Shingles is at least $5,000+, for more interesting higher quality asphalt shingles around $7000+, for Wood Shake, Metal and Slate roofing the price will be substantially increased by doubling or even tripling – depending on your personal tastes and preferences plus your ability to afford the project.

Always hire a contractor with good roofing experience in the material field you select.  Remember, an asphalt shingle installer may not be a sheet metal seaming roof installer!

Quick Notes: Roof Replacement Process

Replacing an average sized Asphalt roof professionally make take as little as 3- 4 days. The replacement process is as follows:

  • Remove all of the existing shingles, dispose
  • Remove old flashing to expose underlying plywood

– Any damaged or rotting wood must be replaced to prevent causing structural problems in the future.

  • Remove tar paper

– Check all the sheathing nails and then re- fasten any which are loose.

  • Replace all rotting/ damaged wood

– Attaching to rotting/ damaged wood causes the new shingles to slide out of place making leaks appear in your new roof.

  • Install new underlayment over sheathing

– Tar paper is the most prevalently used form of underlayment material, although we prefer to use quality GAF Deck Armour (SEE LAST DIAGRAM)

  • Install ice/ water shield at the gutter end lines

– We use GAF roof leak barriers such as Weather Watch and Storm Guard (SEE LAST DIAGRAM)

  • Make sure there is proper ventilation

– This should be done at the peak and bottom of roof as well as the beginning of all shingle starter areas.

  • Install under- row starter shingles

– A simple 3 tab shingle row can be installed to give a clean finished edge.

We want to take a moment here to address an item that is very important, but most often overlooked in standards of practice for roofing and siding installations:

  • Proper use and installation of drip edge and flashings

– Unfortunately and so many times we see improper installation of drip edge or flashings, with the end result of major repair costs to homeowners.  The purpose of these metal strips is to direct water away from potentially susceptible areas for water access into the home.  Flashing works by overlapping coverage. Inexperienced contractors will often install the flashing on top the finish materials, not overlap flashing and leave open seams which do not provide water protection and actually encourage water seepage into the roof or behind windows, doors and siding! We also see incomplete flashings create serious water damage. Look at our schematic drawings for proper installation, then look at the photo of the results of an improper installation!

The roofer stopped his aluminum step flashing at the roofs edge instead of extending beyond the gutter line. The siding contractor then came and he failed to add / continue the flashing off the roof and over lap his siding.  Finally, the builder and inspector missed it! In this case the roof flashing ended right at a seam in the clapboards which is literally an opening for moisture to get behind the siding.  The gutter was removed to investigate, revealing serious  ROT

roof flashing problem (note staining)

Roof Flashing Problem (Note Staining)

incorrect flashing result: hidden damage

Incorrect Flashing Result:Hidden Damage









  • Kickout flashing diverts water away from wall, into gutter

    Kickout Flashing Diverts Water Away From Wall, Into Gutter

  • Install Aluminum or Copper Flashing with Silicone Sealant
  • All new roof replacements should use aluminum/ copper flashing.
  • Silicone caulking is the most suitable way to seal the new flashing to chimneys, walls, etc. Silicone is flexible and waterproof, is an excellent adhesion for bonding to metal.
  • Use kick-outs where roofs meet side walls (right->)
  • Install the Ridge and Hip Caps

–  These are the final steps for protection against water damage, the ridge cap is installed on the peak (top) of the roofs or ridge caps to weatherproof and hip caps are installed on hip roofs, on the edges between sections of the roof to weatherproof.

  • Replace all the existing pipe boots

– Don’t forget to take care of those little, inexpensive items such as the rubber pipe boots.  We’ve often been called for ceiling leaks due to a simple repair such as replacing the cracked old pipe boot, yet the homeowner now had to pay a drywaller and painter, sometimes flooring tradesman to replace the damage caused by leakage through the pipe collar’s cracks!

  • Install Diverters

– Diverters must be installed around chimneys, against walls, and any other areas where water drains directly into. These are also flashings for water control.

  • Install shingles of your choice


  1.  ‘Square’– Is a unit of measure equaling 100 feet.
  2.  ‘Pitch’– Is a numerical measure of the steepness of a roof; it is calculated as every inch the roof will rise for every 12” run.
  3.  ‘Vent’– Runs along the ridge of the roof to release trapped heat and vapors, preventing the roof from buckling and deteriorating over time.
  4.  ‘Composition’– Another word for Asphalt Shingles.
  5.  ‘Spot Repair’– Repairing a small portion of the roof rather than replacing the entire roof.
  6.  ‘Substructure’– Underlying structure or any underlying structure that supports or gives strength to the roof, aka decking; commonly plywood.
  7.  ‘Hand Split Shakes’– Wood shingles split from a block of wood (normally cedar) using a froe.
  8.  ‘Flashing’– Pieces of sheet metal attached around the joints and angles of a roof to protect the roof against leakage.
  9.  ‘Tar Paper’– A heavy paper coated or impregnated with tar for use especially in waterproofing roofs.
  10. ‘Underlayment’– A thin layer of paper used as an extra measure of protection against extreme weather, condensation and excessive temperatures.
  11. ‘Sheathing’– Is a protective covering or something that encloses and protects, e.g. a covering of boards on a building’s framework.
  12. ‘Ice/ Water Shield’– Is used to protect roofs of homes from being damaged by ice dams that form when water collects on a frozen roof after it rains, causing sags and leaks on the roof.
  13. ‘Starter Shingles’– refers to the first row of shingles that are put on at the bottom of the roof. These overlap the Eave metal and are normally turned upside- down and backwards in order to produce a good straight line along the leading edge of the eave metal.
  14. ‘Drip Edge’– A metal strip that extends beyond the other parts of the roof and is used to direct rainwater off and away.
  15. ‘Hip and Ridge Cap’- Cover of metal, tile, asphalt shingle, et cetera, over the ridge, sealing the joint between the two sides of a pitched roof.
  16. ‘Silicone Sealant’– A flexible and waterproof rubber- like substance normally used to seal roofs to chimneys, walls, et cetera.
  17. ‘Pipe Boots’- A prefabricated flashing piece used to flash around circular pipe penetrations.
  18. ‘Diverters’– Is a shaped slit of metal design that fits at the edge of your roof and keeps rain from falling in areas you want to protect from rain runoff.
  19.  ‘Gutter Guards’– Can be made of a number of materials; essentially they cap the gutters to prevent leaves and debris from clogging drainage.