Plumbing a Room Addition in Lake Forest: Tying New Bathrooms and Wet Bars Into an Older Home
Adding a primary suite, a bathroom or a bonus room with a sink puts new demand on old pipe. How to size supply lines, route them and decide whether the rest of the…
Lake Forest has plenty of homes that have outgrown their original floor plans. In the older El Toro neighborhoods and around the Lakes, families add primary suites, extra bathrooms and family rooms with wet bars. Foothill Ranch and Portola Hills owners convert lofts and bonus rooms. Every one of these projects asks the existing plumbing to do more, and planning the water supply early saves trouble later.
Start with what is already there
Before drawings are final, it helps to know what the house has now. Is the main line large enough? Is the existing pipe copper, galvanized, CPVC or something else? Where are the main shutoff and water heater? Original pipe in a 1960s or 1970s home may already be near the end of its life, and tying new fixtures into it can make pressure problems worse throughout the house.
Sizing the new branch
An added bathroom with a shower, toilet and double vanity adds real demand. The new branch should be sized to keep pressure steady when two showers run at once. In some homes that means upsizing part of the existing trunk line, not just teeing off the nearest pipe.
Routing options
- Through the attic, common in single-story ranch homes.
- Under a raised floor or through a crawl space on some older houses.
- Inside new walls of the addition, with a connection point inside the existing house.
- From a manifold, which gives each new fixture its own line and shutoff.
PEX-A is well suited to additions because it bends around framing with fewer fittings and handles the long runs that additions often require.
Hot water at the far end
A new suite at the far end of the house can mean long waits for hot water. Options include a dedicated recirculation line, a point-of-use heater or relocating the main heater. It is far easier to plan this while the walls are open.
When to repipe the rest of the house
If the existing pipe is aging, a whole-house repipe at the same time as the addition gives you one system, one inspection sequence and one set of patched walls. It also avoids a newer addition sitting on top of an older supply that is likely to leak.
Permits and coordination
Additions in Lake Forest require City building permits, and plumbing is inspected along with framing and other trades. Your general contractor or architect handles the overall plans, and the plumbing scope fits into that schedule. HOA approval may also be needed in many tracts.
Related reading
Read our guide to bathroom remodel plumbing, or see PEX pipe sizes explained. Neighbors can visit Irvine, Mission Viejo and Rancho Santa Margarita, or see all of our service areas at repipeinc.com.
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Written by Repipe OC · CSLB #1087885 C-36 · 23821 Hillhurst Drive, Laguna Niguel, CA 92677 · (949) 524-2362