Saturday, June 28, 2014

Protecting your cottage roof from wind damage off the lake

Q:

I’m having a cottage built on the water of the great lakes and I’m worried about the high winds. Can you give me any advice on what type of roofing products I should put on my house so that they won’t get damaged?

A:

Since I have a place on Lake Huron I see a lot of my neighbours who have had wind damage to their cottages. A lot of these cottages are newer cottages and are constantly being repaired after the big storms that come off the great lakes. Well that's good for the handyman that comes to fix the roof it gets to be hard on your wallet.

Let’s start with your roof;

Asphalt shingles

Most cottages are still using asphalt shingles, there's several reasons for this; the availability and range of suppliers that sell them, they are easy to install and the cost of them. There is nothing cheaper than an asphalt shingled roof.

Those are the pros, the cons on the other hand of having an asphalt roof is that they are held onto the roof with a maximum of only 4 shingle nails, the bottoms of the shingles are held in-place by the sun melting a tar strip that binds to the shingle below it. If the sun doesn’t melt this tar strip or the tar strip doesn’t bond to the shingle below it then in a strong wind the shingles blow off and you have to have them repaired or replaced.

If your budget doesn’t allow for anything else then an asphalt roof then you need to install a waterproofing membrane underneath the shingles. This will help protect the structure of your roof from water damage when the shingles do fail on the roof. There are many different types of waterproofing membranes; any of them will do if all you are doing is using them as a backup to wind, rain, ice and snow damaging your shingles.

There are asphalt shingles today that have been engineered to withstand higher winds; they are made with a fibre glass mat embedded in them. This will help the shingle from tearing when the wind lifts it off the roof and can help your roof survive a bigger wind.

They also make an asphalt shingles that are multiple layered. This makes the shingle a lot heavier than a normal asphalt shingle. This shingles should last longer than a conventional shingle and the added weight allows it to lay better on the roof during wind storms.

Both of these shingles cost more with the multiple layered shingles being significantly more expensive to purchase and they take a little longer to install as well.

The problem with asphalt shingles is that once the wind gets underneath them then they lift off a lot easier than you would think regardless of the weight. Because the shingles melt together in the hot sun they tend to come off the roof in large clumps. This leaves large areas of your roof exposed to the weather.

Steel roofs

There are several different types of steel roofs on the market and they are priced accordingly with steel roofs that are not as durable being at the low end of the cost scale and the high durability being the top end of the cost scale.

The cheaper steel roofs are the ones that are installed like shingles; they are called steel tile roofs.
Steel tile roofs are made from a lighter gauge steel, it allows them to be installed quicker and they are cheaper to buy because of the less steel material in them. They are installed with nails or screws in the top flange with the next shingle above covering it. The bottom of the shingle is left unsecured relying on the stiffness of the steel to hold it in place.

There are cons with this roof, they do not have the strength of a conventional steel roof and high winds can lift them up and remove them from the roof. A lot of steel tile shingles are made from such thin steel that they do not do well with weight on top of them. They will fold or dent, this means that you are not suppose to walk on them and heavy snow loads can cause them to dent. These shingles also do not do well with flying debris as they are thin, steel roofs are installed with strapping underneath them to allow the roof to breathe. This air space allows the steel tile to be punctured; this can allow the weather to penetrate into your home causing water damage.

The more expensive steel roofs are the ones that we general contractors refer to as lifetime roofs. These steel roofs should last as long as you live in the home. The average warranty on a high made steel roof is 50 years and that is usually the paint warranty on them. As long as the paint stays on them then the steel roof should technically never rust and never fail.

These roofs are made from sheets of steel that are made from a high quality steel that is thick and rigid, it can be walked on, jumped on, take a snow load and will withstand hurricane force winds when installed properly. They are made to be impact resistant from flying debris and will not be bothered from tree branches scrapping over the material. These roofs come in sections that are 3 feet wide and as long as your roof is from peak to soffit.

They are installed one at a time with an overlapping flange on each side that gets screwed together on the vertical seams. Because these sheets of steel are ordered to fit your roof there is no joint in the roof horizontally, the sheets of steel run from the peak of the roof down to the facia. This makes the roof attached extremely durable to the pressures of the wind coming off the lake.

Enviroshake

There is one other type of roof that I would recommend to stand up against the hurricane type force winds that come off the great lakes, it is a specialty product called Enviroshake.

Enviroshake is a roofing material that is made from recycled materials and ethanol waste products from corn. The material that is created is an extremely durable product that is made to look like cedar shakes. It comes with a 50 year warranty and is installed with ring nails that are usually used for conventional cedar shake roofs; they are installed the same way you install cedar shake roofs with the nails being installed at the top of the Enviroshake and the next shake covering them.

One of the biggest differences between Enviroshake and Cedar shakes is that Enviroshake never warp, rot, twist, split or full apart. The material is so durable that you use a skill saw to cut the Enviroshake, a knife will not penetrate enough through the shake. The material does not bend and always lies flat on the roof. This stops the winds ability to get underneath the Enviroshake and lift it in high winds. This material will stand up to whatever the great lakes can through at it.

The downside to Enviroshake is it is by far the most expensive roofing material that you could install on your roof, the look and durability do pay for itself overtime but you have to be able to afford it in the first place.

Rob Abbott
Village Builders Inc.



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