When installing a new roof system on a sloped roof application, it is necessary to incorporate a balanced ventilation system. This is required by shingle manufacturers to validate their material warranties and has been determined to be a best practice in the industry.
Correct and adequate ventilation serves to help mitigate the occurrences of ice damming, but only forms part of resolving such an issue. (Ice damming is the result of air leakage within the attic, where conflicting hot, moist air, meets cold, exterior air, and effectively condensates).
A balanced ventilation system involves having continuous intake (usually at the soffit area), which introduces air flow designed to push hot, moist attic air out of the roof ventilators, typically located near the peak of the roof. (Referred to as exhaust ventilation).
Vaulted and cathedral ceiling configurations require the application of a ridge vent system, which provides for the exhaust of each and every rafter cavity. Due to the nature of theses ceilings, the void between supporting roof rafters, forms individual “attic” spaces. So placement of static (individual) type ventilators does not suffice to remove attic air, because they are confined to a given location on the roof.
Homes that have “interrupted” attic designs (characterized by having attic living spaces, functional dormers in the roof line, etc.), are also recommended to employ ridge ventilation for the same reason as vaulted attic designs.
Many older GTA homes were originally built with little or no insulation, particularly in comparison to modern building standards. Over time, many of these homes have had renovations, which have resulted in varied levels of insulation in walls and ceilings. Inconsistent levels of insulation can contribute to causing similar problems as experienced with incorrect insulating and ventilating of attic spaces.
Less Energy, Improved Air Quality
Investing in proper air sealing, as part of a complete strategy involving introducing proper ventilation, and installing sufficient levels of insulation result in a home being thermally efficient, using less energy, and increasing the longevity of the roof system. Additionally, air quality may also be improved.
Air sealing involves first locating areas which are subject to air migrating through the building’s envelope. Common areas include around windows and doors, wall plugs, breaches in vapour barriers, or non-existent vapour barriers, and through penetrations in the roof (such as plumber vents, or bathroom exhaust hoses). The top plates of exterior walls, where they meet roof rafters, are another common air leakage point.
Testing is completed by creating negative pressure in the home, by conducting a blower door test. This work is performed by a credentialed, building envelope professional.
Older, poorly insulated homes seldom if ever, experienced problems with ice dams or mold. Today’s highly insulated structures, tighter windows and doors, have created the need for special consideration, when incorporating a particular component, such as a roof installation, with other factors which may exist in the home’s construction.
For the roofer’s part, their responsibility is to install the materials in a correct manner, and provide for adequate ventilation in accordance with manufacturer standards. It is to the home owner’s advantage to become aware of other components in their building envelope, which may require further attention and correct those items which can contribute to pre-mature roof failure, or complications which can mirror roof leaks (such as ice damming).
Working With Approved Vendors
Avenue Road Roofing works with and can recommend approved vendors, who are experts in the field of interior insulation, air sealing, and building envelope science. We can do so on request of a home or building owner. ARR can work in concert with these specialized experts to provide a complete package for the benefit of our customers.
As part of installing a proper roof venting system, ARR can install baffles at the eaves area of the roof, under the sheeting or roof boards. This prevents insulation from impeding the path of air induction at the eaves area of the roof.
Where homes are designed with roof rafters pocketed between the brick work (usually identified by having very short under-hangs, tongue & grooved wooden soffits, etc.); it is necessary to remove bricks between the rafter spaces, to allow air to enter the attic.
This provides an opportunity to install new continuously vented aluminum soffit panels on the under-hang, and contribute to a low maintenance exterior. If preserving natural wood under-hangs is preferred, individual grill vents may be installed to cover the brick voids.
Contact Avenue Road Roofing to arrange for a low cost inspection, or an estimate, to complete such required work.
In the context of exterior insulation, ARR can provide upgrades in R-value and resulting thermal efficiency. Exterior insulation increases levels of insulation in flat roof assemblies on dormer side walls, gable end walls, and house walls by installing Tyvek insulating wrap and thermal styrene insulation. This can be combined with the installation of vinyl or designer type siding products, which also serve to modernize or upgrade the appearance of a home’s exterior.
The investment in many of these energy retro-fits qualify for the ECO-Energy Grant Program.
Call Avenue Road Roofing to learn more and have one of our specialists discuss what may be possible to improve the comfort and value of your home.