FAQs

What is Breathable Underlayment?

Breathable underlayment lets water vapour escape your attic while keeping outside water from getting in. This stops moisture from getting stuck in the wood, helping prevent mold and rot, especially if your attic ventilation isn't great. It's good for older homes, homes with poor ventilation, or those with older/OSB roofs, or no ceiling vapor barrier.

What is ice & water protection and why 6ft versus 3ft?

Ice and water guard is a thick, self-sticking waterproof layer on your roof that seals around nails. It stops leaks from ice dams, which form when melting snow refreezes at the roof edge, trapping water. In our freeze-thaw climate in London, ice dams can be large. Using an extra layer (6ft) of this barrier gives added protection against even the biggest ice dams.  This is particularly important for houses with large overhangs and lower-slopes, or for any home with poor soffit ventilation.

What’s the difference between the three shingles? 

All three are modern laminated architectural shingles, varying in weight, composition, and appearance. The "Good" shingle is the standard.  "Better" shingles are more robust and incorporate GAF Layerlock® technology for severe weather resistance and Stainguard Plus® with added copper and zinc for algae prevention; they also offer improved color and depth for better curb appeal. The "Best" shingles are the thickest and heaviest, about 20% thicker(!) and contain the most copper and zinc for maximum algae protection and longevity, providing the most significant depth and color variation for the best aesthetic.

Why should I care about ventilation?

Ventilation is the single biggest contributor to the life of your roof.  Most roofs in London and Southwestern Ontario fail prematurely because attic ventilation is not adequate.  In our region it is very hot in the summer and very cold in the winter, so our roofs require working intake ventilation (usually at the soffit) and outflow ventilation (at the ridgeline).  Meg Sim Roofing will calculate the correct ventilation loads for your attic and ensure you have the right balance.  If done correctly, this prevents mildew and dry-rot, combats leaks from ice damming, and adds years or decades to the life of your roof system. 

Want to learn more about ventilation? Check out this great article from our friend Joe Lstiburek in Fine Homebuilding