
Rainwater harvesting means catching the rain that runs off your roof and using it outdoors, mostly on gardens and landscaping. Sun House System specializes in designing and installing residential rainwater systems throughout Littleton, Denver, and the Colorado Front Range.
A rainwater harvesting system is simpler than most people expect, particularly for Colorado water conservation efforts. Rain falls on your roof and travels through your gutters before passing through a pre-filter or first-flush diverter that removes debris. It is then stored in a barrel, cistern, or tank. From there, this collected rainwater can be gravity-fed or pumped to wherever you need it — such as for vegetable gardens, lawn irrigation, drip systems for trees and perennials, or ornamental landscaping. Every residential rainwater system designed by Sun House System is tailored to your roof area, average annual rainfall, storage goals, and end-use pattern.
Rainwater guides: CO Rain Law | Barrel vs Cistern | Rain barrel vs system | Littleton rainwater installs

A barrel stores water. A rain harvesting system is built so that water is ready for the yard, including sprinklers when the design calls for it. On Advanced and Elite packages it can run on a schedule or from an app. Zone control is Elite only. Basic includes a pump and hose spigot, with no app and no zone control.
Collected roof water goes outside: vegetable beds, flower gardens, trees, shrubs, and drip lines.
It isn't drinking water. On most homes, Colorado's two-barrel rule keeps it outdoors on the same property. Details: https://sunhousesystem.com/co-rain-law
Please reach us at Hello@sunhousesystem.com if you cannot find an answer to your question.
Yes, with limits. Most homes on city water can use two rain barrels totaling 110 gallons for outdoor watering on the same property — no state water permit for that setup. Want more storage? That usually needs a well-based permit. Full detail: https://sunhousesystem.com/co-rain-law
No for the usual two-barrel setup. Untreated roof water is not safe to drink, and Colorado’s barrel rule does not allow indoor household use. Keep it for gardens and outdoor watering.
Yes. We help Front Range homeowners set up a compliant two-barrel system: sealable lids, workable downspout connections, safe overflow, and placement that fits reasonable HOA rules. We never promise state approval for larger well-based systems.
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