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scrappy25

screened porch over drainage swale?Enclosing to keep critters out

scrappy25
9 years ago

Greetings, I am planning a screened porch behind my dining room. It will be extending over a broad drainage swale in my yard, The swale is only about 6 inches deep and probably 6 feet wide, it drains water from our backyard down the side yard to the street during very heavy rains.

My contractor (and all 3 contractors that I interviewed for this job) does not think it is an issue to build the screened porch over that on posts, he will cover the ground with weed fabric and put gravel on top. He thinks that will not affect the current drainage.

The screened porch will have a covered roof and eze breeze panels so water will not be going through the floor. It will be a tiled floor over ditra so no problems with insects. However, I am concerned about ventilation.

My question is how to cover the sides under the porch with adequate ventilation to keep out critters and use the higher part as storage for wheelbarrows and lawn tools that usually are stored outside.

Contractor has proposed trellis but I prefer the look of horizontal boards. Here is an example of what I would like to have, from the dixiedelights website. Looks like she painted the horizontal boards to match her hardieboard siding.

So, do you think that if we space the horizontal boards an inch or so apart, that will be enough ventilation for the underside of the screened porch? The porch will project 20 feet into the yard, the swale runs about 15 feet away from the house so will be running horizontally across the furthest 5-6 feet of the porch from the house.

I am concerned about leaving enough space under the horizontal slats for the swale drainage, was thinking of stopping the horizontal decking about 6 inches above the low point of the swale Is there such a thing as dark pvc lattice that we use to cover the gap for critter control but allow water to flow? I think that white lattice would become discolored rapidly from the heavy rains and water runoff.

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