Renovation & Design

MIKE HOLMES: Roof can be the root of a home's problems

When it comes to roofs, the most important thing is a proper structure. If the roofline is wrong, everything else will be wrong, too.

The cold weather is starting to close in. That means there are a few things homeowners should be thinking about getting done before Old Man Winter stakes his claim. Your roof is No. 1. Why is it important? Anyone who has seen the first episode of Holmes Makes It Right will know the answer to this.

We spend thousands and thousands of dollars on everything inside our homes. But what's protecting it all? The roof. If you have a bad roof, it's only a matter of time before you have a bad house. It can lead to heat loss, mould, a rotted-out structure and pests. These problems can travel to other parts of your home, too, leaving a path of destruction.

Most homeowners will call a roofing company to re-shingle their roof. But roofs are much more than just shingles. Homeowners need to know what they should be paying attention to if they want to do what's right for their home.

When it comes to roofs, the most important thing is a proper structure. If the roofline is wrong, everything else will be wrong, too. You can have the best products and the best application methods but if you're putting them over a roof with poor structure, I guarantee it's going to leak.

I've dealt with roofs that seem as if they've been designed to leak. It likely wasn't the intention of the people who built them -- at least I hope not -- but that's what happened. In this case, the roof's structure was poor and designed to slope or dip inward into the home, so instead of a pitch, we get a valley.

Usually when a roof dips, it's because the sheathing is sagging, the roof joists are too far apart or OSB (oriented strand board) was used instead of plywood. But I have seen roofs where the structure was actually designed to have a slope right in the middle.

This doesn't make sense for a structure that's supposed to be directing water away from your home. These low areas create valleys that do not drain. They're bad because they collect snow and rain and allow ice dams to form -- not to mention the heat loss. How do you get enough insulation if there's a low point designed into the roof? There's no space for insulation, so you're going to get heat loss, which is another big problem when it comes to roofs. Some telltale signs that your roof is losing heat include higher energy bills or a leak in your home.

If there's a low-lying area on your roof that collects snow and you also have major heat loss, what do you think is going to happen? You're going to get water pooling when that snow melts. And if the roof design doesn't allow proper run-off, or if the wrong materials were used on a low-slope roof, water will seep into your attic. It's inevitable.

During the winter, you want to see snow on your roof; you don't want to see patches where the snow has melted. And you really don't want to see icicles on your eavestroughs because that means the snow on the roof is melting when it's still freezing outside. This can lead to ice dams that block your gutters and cause water to back up underneath the shingles. Once it's there, it's really easy for it to get inside your home.

Typically there should be roofing paper underneath the shingles to act as an extra layer of protection in case any shingles blow off. It's a preventive measure. But if a roof's structure is wrong, what are the chances that everything else is right? I wouldn't count on it.

Roofing underlayment -- which is an ice and water membrane -- should be installed along the perimeter of your roof and in any run-off valleys. It's used in any areas on your roof where there's going to be extra water flow or drainage. But it can't protect an area that actively collects water. It's a preventive measure -- not a direct line of defence.

Many people spend all their money on cabinets, kitchen floors, tiles and entertainment systems. Yet they forget to spend money on the roof... to protect the cabinets, floors, tiles and electronics. Before anything else is upgraded or renovated in your home, you have to make sure your roof is doing its job.

-- Postmedia News

Catch Mike Holmes in his new series, Holmes Makes It Right, Tuesdays at 9 p.m. on HGTV. For more information, visit . For more information on home renovations, visit


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