Ave You Ever Think Of Your Gutters As Your Rainwater Management System?

You may not have considered your guttering a being an important part of water management system, but in fact they are. While the calculations of how to construct your rainfall guttering system will involve some math, the calculations are reasonably simple but need to be carried out carefully. Once you have finished working out what you need, you can go out to purchase your supplies in order to install efficient gutters in Toronto. Organization and planning are really essential to make sure that you do a good job. Read this guide carefully to help you complete a fully effective installation.

Gutters, downpipes and drains

Essentially your gutters are the front line of your water defense system, they need to gather the rainfall from the roof of your home or your outbuildings and efficiently channel the rainfall to the downpipes. From the downpipes, you need to decide if you want to channel water into your fresh water reservoir for use in your garden for irrigation. Once the reservoirs are full, the excess water needs to be channeled into the drains to get it clear from your property quickly and efficiently.

If your drainage system is inadequate for the job, you are at severe risk of flooding. It is impossible, particularly with global warming, to predict the severity of an extreme thunderstorm and the rain that it could bring. But the key design objective is to ensure that your guttering can deal with the majority of rainfall, should there be a cloud burst your secondary system of drainage ditches and run off slopes will channel the excess away from your home and reduce the risk of your home flooding.


Time to get out your calculator

Well, let’s get started. Here is how you need to organize yourself:

1) Get local information about how much annual rainfall you are going to have to deal with, this information is quite easy to get from your local weather station.

2) Understand what the peak rainfall incidents could be. The worst storms or downfalls, how much rain dropped over what period and which months of the year?

3) Calculate the effective roof area (m2) that you are going to have to deal with. This is essential as it will tell you how many liters you will have to drain during a severe downfall.

4) Once you have worked this out, it is time to get designing:

• Choose a gutter with the right flow capacity, measured in liters per second

• Decide on the positioning of the downpipes, by number and position to get the water out of the gutters quickly and efficiently

• You will need to use the local rainfall information that you have gathered to deal with the two minute crisis. Met offices in Canada and around the world report that exceptional rainfall normally lasts for no longer than 2 minutes. These exceptional rainfall bursts will occur in a 1, 5, 50 and 500 year sequence. Understand the numbers that you need to deal with and plan accordingly.

5) The good advice is that your primary gutter and drainage system should be able to deal with one year incidents. Your plan should be to drain off facilities that you have constructed should be able to deal with exceptional rainfall when your gutters and drains are overwhelmed.

How much rainfall in Canada should you expect to deal with?

A minimum design requirement should be as follows; an intensity of 75mm/hour per m2 results in a flow rate of 0.022 liter per second. So clearly you need to calculate the totally square meters of your roof and how many gutters you plan to install with drain pipes to channel the water away. Next you need to consider the pitch of your roof. Essentially the higher the pitch of your roof the faster the water will run into the gutters. Keep this in mind; a roof pitch of just 10° will deliver water far slower than a roof pitch of 45°.

So the smaller your roof horizontal roof area and the greater the roof pitch will increase the amount of water that you will need to deal with during a severe downpour. A good piece of advice from the experts in gutter installation is to really concentrate on the positioning of your downpipes.

Looking at this in more detail you should plan to install downpipe drains before the flow of water hits a gutter angle, either right angle or less acute. The reason for this is quite obvious, but worth repeating. Water can barrel along a longer gutter run. When it hits the angle it will wash over the guttering and waterfall to the ground below. By installing drain pipes before the gutter corners, the risk of this happening is considerably reduced and the potential for flooding or water damage to your walls and floors will be considerably reduced accordingly.