Soffit ventilation

Attic inspections consider 3 major factors:  R-value (measure of thermal resistance) of current insulation, Continuity of ceiling vapor barrier and Ventilation.  Ventilation is evaluated in 2 ways: Intake (usually in through the soffit cavities) and Exhaust (through vents installed high on the roof’s ridges).  Your home’s attic and roof depend on proper ventilation to exhaust heat and moisture from the attic space.  Whenever ventilation is limited, or out of balance between intake and exhaust, issues arise such as condensation.

Most homes draw intake ventilation through the Soffit cavity.  The soffits are the underside of the roof where it overhangs the exterior walls of the building.  Older homes, prior to the 1970’s had soffits made out of sheets of plywood that often had very few or sparse vents cut into them.  The adoption of perforated aluminum soffits came in conjuncture with an understanding of the importance of Attic ventilation that for decades became the standard in new home construction.  Unfortunately all too often in the renovation market contractors install new aluminum soffit over top of existing wooden soffit, greatly limiting air flow.

In cases where Attic intake ventilation is limited due to wooden soffits, aluminum covering wooden soffits or plywood stops installed between the attic and the soffit cavity we must pursue additional measures. These measures may involve attempts to bash out plywood stops from the Attic side.  Not a very effective technique but sometimes successful.  Removing the wooden soffits and replacing with new perforated aluminum soffits.  We can often remove the plywood stops from the outside where access is improved with the existing soffits removed.  The best way to address the intake ventilation issue but surely a costly exercise.

The third is the installation of Lower roof intake vents.  This practice has become much more commonplace in Calgary since it has been adopted by New Construction developments in adherence to local fire regulations.  High density residential construction is no longer permitted to utilize perforated aluminum soffits so they install lower roof intake vents during construction.  In the renovation market we can use the same intake vents to create ventilation in Attics where the soffit cavities are poorly vented.  Intake vents are installed around the perimeter of the roof, or specifically in problem areas, down near the edge of the roof.  Always above the exterior wall plate and preferably above the finished height of the current/new attic insulation.  This allows fresh air to be drawn into the Attic space, above the perimeter of the Attic insulation so it can then cycle through the attic and exhaust up through the vents installed at the ridges.

lower roof intake vents allow for Attic intake ventilation through the lower parts of the roof

lower roof intake vents allow for Attic intake ventilation through the lower parts of the roof


IDEAL company infographic

We’re working on some new advertising for IDEAL.  Our infographic outlining all of IDEAL services is now complete.  Check it out!


IDEAL infographic

Attic / Roof intake ventilation

There has been quite a bit of interest in Attic ventilation recently.  The new low profile lower roof intake vent systems are garnering attention for their sleek design and minimal appearance on the roof.  Check out the Lomanco page for more details. CLICK HERE


low profile lower roof intake vent

low profile lower roof intake vent

Low profile roof intake venting as good as advertised

We just finished a re-roofing project where we installed the Lomanco Deck-Air low-profile intake venting system and it is as good as advertised!  The product is similar in nature to ridge venting, where the majority of the vent is covered by the shingles.  This leaves very little exposed and allows for a more stream-lined appearance compared to traditional roof ventilation.  When combined with an upgraded shingle like the GAF Grand Sequoia which was used in this example below you are left with a minimalist installation.

Grand Sequoia incl. low profile Lower intake venting

Grand Sequoia incl. low profile Lower intake venting

New Owens Corning Impact Resistant Shingles

Owens Corning has released an extension to their popular Duration line of shingles that is now available in the Calgary marketplace. The Duration Storm shingle boasts the advantages of Sure Nail technology to aid installation and prevent nail penetrations in the shingle, coupled with Weather Guard technology which reinforces the shingle to resist impact. Check out the following video for more details!

Wood shake roof conversions can require extra effort

wood shake tear off reveals gaps in roof deck

after removing the wood shakes it was revealed that the substrate required additional material

You never know what you’re going to find when you take off an existing roof. In this instance the asphalt shingles had been installed over a wood shake roof. It became apparent as to why when we removed the cedar shingles. This heritage home had 1″ x 10″ slats for a roof deck substrate that were spaced up to 4″ apart.  The solution was to inlay 1″ x 4″ pieces into the gaps to create a continuous surface.  Just another example of some of the unknowns that must be addressed when you renovate.

fills gaps in roof deck

the gaps in the roof deck had to be filled to create a complete surface on which to install the new asphalt shingles

Proper install of Plumbing Boots

proper plumbing boot install

plumbing boots or “oaties” are rubber gaskets that surround the plumbing vent stack to prevent water where the stack penetrates the roof deck

When evaluating the quality of install of Plumbing boots please consider the following:
– shingles overlapping the flanges of the vent are solid pieces
– a minimum 1″ space between the vents base and the shingles surrounding it
– tar over all nail heads

Proper Gooseneck Vent install

proper gooseneck vent install

Gooseneck vents are used to exhaust bathroom fans, kitchen exhaust fans and dryer vents


When evaluating the quality of a Gooseneck vent installation look for the following:
– shingles overlapping the flanges of the vent are solid pieces
– a minimum 1″ space between the vents base and the shingles surrounding it
– tar over all nail heads

Roofing Tar treats the symptom rarely the problem

Roofing Tar, or sealant, is used to address small penetrations such as nail heads.  Excessive amounts of tar are often a sign of prior leaking.  This should be taken apart and addressed properly during the re-roof process.  This could also be a result of the bricks being installed too tightly to the roof deck preventing a proper installation.


Options for vaulted ceiling insulation

Sometimes the best time to insulate an attic is prior to the installation of ceiling poly and drywall.  If the finished attic space is extremely tight and access is limited please consult your Insulation expert for ideas to create the right vaulted ceiling insulation plan.