Plumbing over Basement Layout

Well in some cases you can't avoid it.  I would say make sure you can get to it in case of an issue and before you build maybe replace any old valves or piping you see as a potential issue.  At my old house this is exactly what I did.  I had 2 copper pipes over the layout that were definitely old.  Just replaced them before building the layout.

In addition @MartyE's excellent advice above, try to avoid putting anything directly under the potential problem spots.  Also be aware that water from a leak can travel along pipes, air ducts, joists, etc. before falling to the floor.

Congrats for planning ahead.

Look at putting it someplace else. I've had toilet leaks / overflows. Or put a lined catch box under it with a water sensos in it.

The cold water feed to an upstairs sink started slowly leaking.  The water eventually ate through the wallboard sky above my layout:

As you can see, the layout was fairly finished in this section.  I had no choice but to open it up and repair it

I used a SharkBite fittings, so there was no soldering flame around the layout:

How I got up there is another issue

If you're going to finish the ceiling, I recommend making removable access panels in case you need to get into any problem areas. Or, at the very least, take photos of what is there before finishing the ceiling. I have drainage traps above my train room and have photos of where they are in case I need to get to them and clean them. If that ever happens, I'll make a removable panel instead of patching the sheet rock ceiling.

Another option might be a suspended or "drop ceiling" with removable tiles. It's definitely more expensive than sheetrock, but you retain easy access to utilities.

I'll probably be in a similar situation, where the best option for the layout is under all the plumbing. While the floor and walls will be finished, the ceiling will be left open but painted. Some of the plumbing is showing its age, so I intend to have it replaced before we do any finishing or build a layout. Usually not practical to remove all risk, but I will feel safe enough by replacing the most likely trouble spots.

I put in a drop ceiling above my layout and when I had to replace leaky copper pipes with plastic it was a do able job.  As a result of a few pin holes, I only had to change out two fiberglass panels.   I thought the installation of the grid work was easier than sheetrock, and I have done a lot of that.

Marty

Plan ahead. If the copper is not leaking, leave it. The quality of "new copper" pipe is nowhere near what the old was. New stuff gets pin-holes in no time.

Couple options- replace the copper with PEX pipe. It's flexible enough to bend up into the floor above so there would be no fittings above the layout area, and as of now the stuff has been in use for about 10 years and is rock solid. Without moving the toilet, the trap and waste piping aren't going anywhere so I would add a pan under the toilet to catch any wayward water. A water-bug alarm would alert you if the pan is holding water.

figure on how you would get into the ceiling when you have to (and you will).

good luck.

@John Sethian posted:

The cold water feed to an upstairs sink started slowly leaking.  The water eventually ate through the wallboard sky above my layout:

As you can see, the layout was fairly finished in this section.  I had no choice but to open it up and repair it

I used a SharkBite fittings, so there was no soldering flame around the layout:

How I got up there is another issue

these are Pro-press fittings that are installed with a hydraulic crimping tool. Since these came on the market I haven't picked up a torch and solder again.

Sharkbites are OK but are press on fittings.

@John Sethian posted:

How I got up there is another issue

Rube Goldberg would be proud of you, John.

@mwb posted:

Rube Goldberg would be proud of you, John.

And Michelangelo would have hired John in a heartbeat

And OHSA is very proud 👏

In the first portion of my basement layout, I put a drywall ceiling up over it, painted white to reflect light. I have had to cut through it in one place to install a shutoff valve for an outside faucet. The hole is not visible behind the valence, so I did not need to patch it, and I have access to the valve. For the bulk of the ceiling over the layout and in the center of the room, I air-stapled black landscape fabric, which is easily cut for access to plumbing or electrical fixtures. In one place, I cut a flap to give access to two valves, held up with velcro. The only problem I've experienced with the fabric is that it is not opaque. Lights behind the valence can bounce light up through the fabric and over the valence into the center of the train room. It is much much cheaper and less labor intensive than any other ceiling option. I learned about it on the OGR Forum.

My home is almost 100 years old. The black pipe hot water heat is original. The domestic water copper is a replacement of unknown vintage.

I did rewire all the old knob-and-tube accessible from the basement before putting up the ceiling cloth.

I do have a plastic pan under the washing machine with a drain that empties directly into the sump. This floor to ceiling pipe is behind the backdrop. Before I had the pan or a layout, I had 2" of water in the basement from the washer.

I have had a drip from a valve on my layout--a bad O-ring on a bleed--no serious damage to the layout and less than $1 to fix. Who can say about the future, though? My last plumbing leak did in the foyer ceiling, but not a drop on the layout.

Personally, rather than spending $$$$ on plumbing that still works, I'd put the dollars into the hobby and fix what breaks when it happens.  There are things I'd do differently if I were starting over. Maybe a future plumbing leak will force some improvements?

Marty offered sage advice as always.  

When I redid my kitchen, I thought of adding a second dishwasher.  When I looked at what at that meant with pipes running above my layout, I said no.  Second dishwasher more a luxury than a toilet.  I would ask a plumber you trust their advice, and go with it.

John

You fellows are bringing me back to my friend’s basement He had a 40’ layout with water pipes over it. There were small boxes hanging with wire. Inside the boxes were plastic containers. He had a whole ritual of emptying them. Thanks for the memories.

We converted part or our attached garage to a laundry room. One evening we heard the sink cold water supply line burst and in the time it took to investigate and shut the water of we had a waterfall running down the stairs to the train room in the basement. Lost sereral boxes that were on the floor under the layout.  If we had not been home it would have been much worse.

I put a drop ceiling in our basement. Nothing covered up with a drywall ceiling. easier to fix leaking pipes and running wires.

Plus,  We have Forced Air HVAC and wanted access to the dampers.

Thank you for all the thoughtful responses