I am sure many of you have seen the news article on the homeowner in Raleigh that purchased a home and when he went to sell it he found out it was over his 30% impervious surface limit. This poor guy purchased the house like this and nobody caught that it was over the limit until he was ready to sell and as a result he had to spend thousands to tear out walkways and a patio.
First of all; what are impervious surface limits? Impervious surface limits are the limits on what you are allowed to develop on your property to help preserve water quality and reduce water runoff. In most of Wake County and the surrounding areas the most you can develop of your property is 30%. Some areas have a much lower allowable percentage of what can be developed. Some customers in the Swift Creek Watershed area have an allowable impervious limit of only 9-12% and the same is true of Barton Creek and Little River watershed areas. These limits should be labeled on the property survey you most likely purchased when you purchased your home. If not you can always call the county and see what your limits are.
Many people think that because most sheds are built on skids and concrete leveling blocks and not completely on the ground and water can run under them that they do not affect impervious limits. Unfortunately any covered roof section such as a shed or carport does affect impervious surface. When we pull a permit in Wake County we are required to do an impervious surface calculation based on what is on the property and what is being added to the property. Sometimes our customers are shocked to find out that their limits are so low and they can’t get the size they want. We have even had a few customers purchase a brand new home with the intention of installing a shed or a patio and then they find out they are already at their limit.
We are here to help you through the permit process and will help with the impervious calculations. Please feel free to contact us with any questions over this issue that has become such a hot topic in our area lately.