Ask the Roofing Expert

May 2012 Article

Easter has passed and Spring Cleaning is truly upon us. Attention should not be limited to home, garage, and the yard… the roof gutter system should also be thoroughly cleaned— especially the downspouts. A thorough cleaning helps to prevent water and ice from backing up beneath the shingles during the following twelve months. When the roof sheathing gets wet, the shingles that are nailed to the top of the deck will prevent the wet sheathing from properly drying, and bacteria will set-up that causes rot. When the sheathing rots, this process continues and will eventually infect the fascia boards and the roof trusses. The eaves sheathing is easily checked by running your fingers along the roof overhang. The shingles usually extend past the roof deck by one inch; when cleaning out the eaves trough just reach your fingers under the shingles and you will feel the solid wood sheathing—or you will feel ‘mushy wood’ or if the sheathing is Oriented Strand Board (OSB), you can grab the wood edge and it will just break off in your fingers.

If you are not opposed to climbing onto the roof, you should also check-over the shingles for missing or loose tiles; for cracked or missing caulk; for lifted or loose flashings and vents. High wind can cause roof damage that is not readily seen from the ground. Many roofing companies (Aaron Roofing & Skylights Ltd. included), offers free roof inspections when they are hired to clean-out the eaves trough and downspouts.

This cost is usually very minimal ($125 to $225) and they will do a thorough roof check, and if repairs are nominal will even do the re-caulking, etc. for $75-$125 while they are there.

Any homeowner having their roof replaced should insist upon the installation of eaves ‘dripedge’ plus eaves ‘Water/Ice’ membrane prior to the installation of the roof tiles. When eaves trough is being replaced, it is also a good idea to have the metal leaf guard included. This will prevent the need for annual gutter clean-out, and it is not a huge additional cost (get a few quotes).

Responsible home ownership involves regular maintenance. There are always willing ‘experts’ available to assist with this process; however, most of the requirements are fairly common sense and can be done by yourself.

 

 

April 2012 Article

We did a Pine Shake roof conversion to asphalt; replacing the shakes with Architectural fiberglass/asphalt shingles during September of 2011.  The customer advised us that the large skylight in the ‘Open Beam’ area of the roof was leaking, so we also replaced the skylight curb and the skylight.  When the shakes were removed, we noticed some sagging sheathing so we told the homeowner that there must be a condensation problem. Adding soffit vents to that side was the suggestion.  This would allow eaves-to-ridge air flow between the roof trusses to facilitate the sublimation of hoar frost that may collect during very cold periods (sublimation is the process of ice turning into vapor without going through the water stage).

The following winter, water began coming through the ceiling and downthe outside wall of that open- beam area of the house. The homeowners were convinced that the roof was leaking (in particular the skylight because that is where it leaked prior to the roof conversion).  When I came to analyze the problem, I saw two feet of snow on top of a large sheet of roof ice, interspersed with many areas of dry, exposed shingles.  I told the homeowners that the home interior was not sealed properly, and that warm, humid eighty degree air was escaping into the frigid exterior ‘roof truss’ area forming ice during very cold periods, and melting when outside temperature increased and that is causing the interior water event. They would not accept this reasoning because the past ‘roof leak’ was much less than what was currently happening.  I explained that the old shake roof held the snow and ice two inches above the roof sheathing, some air circulated between the shake layers, and the wood shakes presented some insulation qualities which modified the cooling effects of the ice/snow.  This explanation was not accepted.  I had to open-up the roof to look inside the trusses.We cleared the snow/ice from the shingles, and then removed shingles and roof sheathing; the insulation was soaked!

We discovered that the vapor barrier was not sealed prior to the installation of the drywall, which allowed air seepage at the walls. We also found that the builder had installed a beam in the centre of the ceiling, but the roof sheathing and beam met, thereby cutting off any eaves-to-ridge air flow.  The new roof on that side of the house has to be removed; then two-by-four strapping has to be installed above the roof trusses prior to installation of new sheathing, in order to allow a two inch air flow space.  The vapor barrier must be sealed prior to replacing all of the insulation, to prevent future condensation problems.  The interior has to be replaced once the roof problems are corrected… drywall, floors, paneling, open-beam hardwood, etc.

I’m writing about this problem because ‘lack of proper attic ventilation’ is a huge problem; often condensation problems are misinterpreted to be roof problems.  If your home is costly to heat in the winter, have the attic checked for proper ventilation and insulation, especially if one or more ceiling stains occur after an extended cold period.  If you think that ceiling stain (s) are a result of a roof leak, and you get roof replacement quotes, the roof  inspectors are looking at just the roof unless you specify another problem.  Always call the correct experts when you are looking for answers.

 

 

March 2012 Article

Windstorms that gust 140 kilometers per hour (or more) seem to be occurring more frequently.  When strong winds, with even stronger gusts, blow over shingled roofs a ‘rippling effect’ which loosens the adhesive seal-strips that manufacturers place on their products allows Blow-offs to occur.  It is very unlikely that these shingles will properly re-seal on roofs older than one year because the sealants are too set to reactivate.

New roofs less than a year old will probably reseal once the hot summer days come, unless a ‘dust layer’ has settled onto the seal strips.

Repaired shingle roofs should always be hand-sealed to ensure that they never lift again.  It is also a good practice to hand-seal any shingle roof slope that displays ‘lifted shingles’ during high wind conditions.  Install a tube of roof sealant into a caulking gun, and squeeze a bead of caulk beneath the bottom shingle edge to solve future ‘lifting’ problems.

Roofs that are shingled with products that are no longer available (such as interlocking shingles, or renaissance shingles) will have to be replaced with different products.

If the replacement product design is much different (i.e. a ‘strip’ shingle replacing an interlocking shingle) it may be necessary to replace the fixed flashing behind siding, or to use ‘shim flashings’  in-between the fixed flashings in order to maintain proper water run-off.  Similar problems occur when converting a shake roof to a shingle roof—the flashings are much different.

High winds effect all roof products!  Winds that blow steadily are not as much of a problem, as are the very ‘gusty winds’.  Gusts create sudden ‘lift’ areas, and it is this ‘rippling effect’ that acts like a crowbar to effect blow-offs.

If in doubt regarding correct repair procedures, so research or

Ask The Experts®.

Visit our new site  www.aaronroofing.ca

 

 

November 2011 Article

With a Calgary Winter just around the corner, it is still not too late to give your older roof a Fall ‘Tune-Up’!  Roofs past their prime often have loose flashings and vents which allows water and/or ice to creep beneath the protective roof covering.  It is best to secure flashings & vents by removing any lifted nails and installing appropriate-sized screws.  Skylights, chimney boxes, and fireplaces often have dried, cracked, loose, or missing caulking that can be removed (if still there) and replaced with fresh caulk.  Loose, cracked, or missing shingles should be replaced; metal valleys should have the shingles lifted and resealed, because caulk hardens with age and ‘breaks in the sealant’ can occur to allow water & ice to enter past the sealant barrier, and then not be able to find an exit.  Once this happens, a dirt trail is established which helps future water to more easily discover the entry into the valley and then onto the roof deck.  Older shake roofs are particularly vulnerable to ‘age leaks’ because the oils in the felt that is installed with every course of shakes is ‘boiled’ or washed out over time, and the felt turns back into ‘water-absorbent-paper’.  The felt disintegrates, and/or rots.  As your shake roof breaks down and turns into much more ‘smaller sized shakes’,  the ‘cracks-on-cracks-on-cracks’ that now appear will allow water to pass through to the roof deck, and then into the attic.  Standard shakes are 24”, and are installed with 10” exposure, which means that there are nails through each shake at approximately 11” and 22”.  Traditional shake roof repairs are effected by ‘removing old shakes and installing new shakes …however, while the nails at 11” high can be removed, but the ones 22” high cannot; therefore, roofers rip out the old shakes, and ram in the new shakes – destroying the felts protecting your roof, and creating new cracks-on-cracks-on-cracks in the process, which will eventually turn into leaks.  A much better way to repair an old shake roof is to install 12” ‘shims’ in-between such crack-on-cracks, thereby retaining the integrity of the felt protection.  If you are cognizant of an aging roof problem, but you’re not quite ready to replace it, an inexpensive ‘Tune-Up’ with a 5-year NO LEAK warranty might be a logical alternative, thereby extending the life of your roof.  Have a good Winter, and call ‘An Expert’.

 

 

October 2011 Article

As Fall approaches, it is a good time to consider the importance of proper attic ventilation.  Improperly ventilated attics are more vulnerable to Hoar Frost that can grow to become ‘sheets of ice’ during extended periods of extreme cold temperatures; then, during a Calgary Chinook it can literally rain inside of your attic which can destroy your insulation, and cause mold and mildew.  An ideally-ventilated attic will have ‘soffit-to-ridge-air-flow’.  This is achieved by having ventilated soffits at the eaves and vented ridge at the peak of the roof, but  do not vent the soffits at the gable-ends… because escaping air from the roof peak would be replaced from the closer soffit vents at the gable ends rather than pulling air into the attic from the eaves.  Similarly, it is advisable to  close off any ‘other’ venting such as gable-end vents, roof turtle vents, etc.  A properly ventilated attic will allow the home to be warmer during the winter because the ‘super cold’ midnight-to-6:00-AM air can be replaced with warmer morning air surrounding the eaves; also, the house will be cooler in the summer because the ‘super hot’ 1:00 PM-to-4:00 PM afternoon heat can be replaced with cooler evening air allowing you to sleep more comfortably at night. Another reason to have ‘soffit-to-ridge’ venting is that during high humidity and sudden cooling temperatures, the snow/ice accumulation on the roof at the eaves, creates a situation where the roof deck become ‘wet’ under the shingles, as well as the attic underside, because moisture is attracted from the air to anything that is colder than it is.  Soffit-to-ridge air flow dries this area faster than static air will, plus when hoar frost accumulates, sublimation can occur (the frost will turn to vapour without becoming liquid first).  It is extremely important to have soffit venting, working with ridge venting in ‘open beam’ ceilings in order to cause air flow between the trusses (your insulation will be much more effective, and retain it’s desirable qualities longer).  Roof ‘turbines’ placed far apart, and near the roof peak, will also work with vented eaves soffits, because the turbine fins are constructed to keep rain & snow from entering the attic (do not cover them in the winter), and to draw the attic air out, creating the ‘updraft’ that is necessary for eaves-to-ridge attic air flow.  Power vents, wind turbines, and ridge venting all work with vented soffits at the eaves to optimize attic conditions.  Most roof ‘turtle vents’ do not give satisfactory results! Have a good Fall & Winter, and protect your home.   If you are uncertain whether your attic is vented adequately, consult ‘An Expert®’.

 

 

September 2011 Article

Fifty years ago I was offering my customers two choices for asphalt shingles…(1) 2 or 3-tab shingles for new roofing applied to a prepared wood deck, or (2) interlocking shingles designed for reroofing overtop of existing shingles.  Today, there are many roofing options   making it difficult for homeowners to choose the best product for their home. I’ll try to shed some light on these options to help people make informed decisions:

1. Today’s most commonly used products are usually the most cost-effective. Fibreglass/asphalt shingles cost $2-3 per sq. ft. (installed) and last up to 50 years;

2. Wood products (Cedar or Pine) normally cost $5-10 per sq. ft. installed, and last from 15-30 years.

3. Metal products cost approximately $6-12 per sq. ft., and have similar lifetime warranties to the fibreglass/asphalt shingle;

4. Concrete tiles and/or slate tiles cost approximately $5-12 per sq. ft., and last from 30-50 years.  Composition products are fairly new in the market; their cost varies widely, and their life expectancy is still unproven.

How, then should a homeowner choose their roofing products?  For the majority of us, budget is a large factor; however, aesthetics is also an important consideration:

•            Concrete or slate, for a European look;

•            Wood for the classic ‘country’ look;

•            Innovative metal products  are designed to simulate wood or tile look. Homes in heavy snowfall areas may benefit from metal’s ‘snow-shedding’ capabilities.

Homeowners have to filter out ‘sales pitches’ that suggest that a particular product is impervious to extreme weather, or offers impressive insulation benefits. In fact, heavy hail, strong winds, and/or extreme water and/or ice-damming can damage virtually any roofing product under the right conditions.  With the exception of ‘Flat Roofing’ which often has to have insulation built into the roof design, normally, the products discussed do not provide significant insulation benefits; therefore, insulation should not be a factor in choosing them.

When choosing a roofing product, one must consider the cost vs. lifespan vs. aesthetics for a wise choice.

 

August 2011 Article

When I began my roofing career in 1957 Calgary, most roofs were of a simple design, and skylights were a new and novel idea for opening-up dark rooms. At that time there were many design and installation problems which often resulted in leaking and ceiling stains. The design problems have been solved for over thirty years; but installation still remains a problem because skylight installation is a very specialized field, and most companies do not have competently trained installers. There are a few procedural basics to properly ensure ‘No Leak’ installation is executed:

 

  1. Have a Water/Ice underlayment installed prior to the new roof;
  2. Seal the skylight box, and/or roof flashing, with the same membrane;
  3. Seal all roof openings with a Styrofoam spray, or proper vapor barrier tape;
  4. Upon completion of the work, properly caulk all shingle/flashing/roof joints;
  5. Test the skylight with directed heavy spray, simulating rainstorm conditions;

…..Lastly, and most importantly, ensure that you have a contractor offering a minimum ‘ten-year’ warranty on the installation workmanship (written and transferable).
These steps are extremely important when having standard roof window skylight (s) installed. Tubular skylights are much more resistant to leakage problems because the roof flashings are rounded, and water/ice does not collect behind them to cause damning issues—AND the inside of the attic does not have to be framed nor finished upon installation; but all you see is natural light coming into the room, you can’t see the sky, clouds, birds, etc.