Although its name may not make it obvious, a flat roof still needs to have a small slope. Without a certain steepness, a flat roof could trap rainwater or snowmelt, which can lead to water infiltration problems inside the building.

To avoid these problems, why not re-slope your flat roof when repairing it?

Here are the steps you should take.

Determine the angle of the new slope

To create a slope on your flat root or roof deck, you first need to measure and determine the span and pitch of your roof so that you can make a detailed plan.

The degree of slope required will vary based on your roof characteristics, as seen in chart 9.26.3.1 of the National Building Code:

 table 9.26.3.1 of the National Building Code for roof slopes

Existing buildings sometimes prevent you from respecting the above roof slope regulations for multiple reasons, for example: wall, door or window height. In this case, a professional roofer will recommend solutions that still allow water to be properly drained from your flat roof.

Removing old flat roof materials

The next step is to remove the old membrane and to have a clean slate for a new roof structure with the proper slope. Even if some materials seem salvageable, be careful since they may not be as strong or waterproof as they appear.

This is also the perfect time to inspect your flat roof insulation and membrane system. Should you notice any problems, you may want to replace some elements while they are more easily accessible.

Installing the new materials and roof covering

The last step is to install the new framework that will effectively support the flat roof sheathing. Without going into details, your first option is prefabricated roof trusses with the appropriate slope. Alternatively, you can create the slope on flat roof trusses or with slope insulation or lumber.

You will then have to cover it with a manufacturer-approved support panel before installing a new waterproofing membrane.

Call Couvreurs Duro-Toit to make your flat roof slope

In conclusion, re-sloping your flat roof can have many benefits that also increase the lifespan of your roof.

If you are looking for a company to make your flat roof slope, Couvreurs Duro-Toit can carry out the work in full compliance with the building code.  today. We are your number one partner for roofing work recommended by CAA Home Services for the quality of our work.

Xavier Trépanier

Xavier Trépanier

Expert en toiture depuis plus de 20 ans, je vous partage mon expérience et mes conseils pour vous aider à mieux comprendre l’entretien, la réparation et la rénovation de toitures.

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