What The Limit Is
Austin caps how much of a lot can be covered by surfaces that keep rain out of the ground. The Land Development Code table sets it by zoning.
| Zoning | Limit |
|---|---|
| SF-2 and SF-3, most house lots | 45 percent |
| SF-1 | 40 percent |
| RR | 25 percent |
How Decks And Covers Count
| Build | Counts As |
|---|---|
| Solid patio cover or roof | Full area |
| Uncovered wood deck with gaps, over open ground | Half the area |
| Loose landscape gravel with no packed base | Not counted |
Put a solid roof over that same deck and the roof counts as a rooftop. That makes the choice between a pergola and a solid cover matter on a lot near the limit. The city glossary lists what it counts.
A Quick Example
A 7,000 square foot SF-3 lot can have 3,150 square feet of cover. If the house, garage, drive and walks already use 2,900, there are 250 left. A 300 square foot gapped wood deck counts as 150 and fits. A 300 square foot solid patio cover counts in full and does not.
It Also Shows Up On Your Bill
The city drainage charge is billed on impervious cover, measured from aerial photos. The city says the bill may be lower for an uncovered wood deck.