Monthly Archives: January 2013


Your drainage gutters are an essential part of your homes protection against water damage. If your house did not have any guttering, your foundations and exterior walls would be compromised by mould and damp. There are many health problems associated with this kind of damp and the structural damage will also be substantial. Working out the volume of guttering required for your home is based on the roof size and the levels of rainfall in your area.

Step 1

Assess the watershed area of your roof and perform any necessary calculations. Make allowances for wind speed during heavy downpours as this will increase the rate at which water collects in the pipes.

Step 2

Calculate the rainfall rate for your area. Many online publications will contain tables where you can check this level for your district. It is important to get an accurate reading, as any other amount will be difficult to process.

Step 3

Make a decision on the guttering required to drain your roof. Perform a simple calculation by dividing the areas watershed amount by the rainfall rate. This will show you the maximum level your gutters can hold and still be able to efficiently draw the water away from the house. For every square inch of cross section 100 square foot of roof can be drained.

It is very important that these calculations are carried out to the letter, as even a small discrepancy in the calculations can lead to choosing the wrong guttering for your home. If you are unsure of what system you should deploy, please contact your local hardware store and a representative there will be able to help you.