Motorhome slab, underground garage upkeep

The overhead sewer lines in an underground parking lot are the “highway” for all of the sewage waste for your building, says Robert Lamoureux. He recommends that these lines be cleaned yearly with a jetter. [PHOTO CREDIT METRO CONNECTION]
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Hi Robert, 

My name is Daniel G., I live in Newhall. 

I’m blessed with a large lot and have plenty of room to add a slab for a motorhome that we are going to purchase. I want to be able to not only park this on the property, but I’d like to be able to hook up to the utilities also, including being able to dump right into my own sewage here at the house, avoiding dump fees when we are “dry” camping at sites. 

Is this possible to do; is it all legal; and do I have to get permits for it? 

I’m guessing because of the extent of what I want, I’m going to have to go the permit route, but if you could let me know if this is even a good idea, I value your opinion and would appreciate your thoughts. 

Thank you. 


Yes, you can tie into the main sewer to your home as long as you hire a plumber and get permits form the city. 

I know many people who do this on the larger lots and it is advantageous to do so. You can either hook up for fresh water with a garden hose, or hard pipe it. 

The hard pipe should be done at the same time you pull the permits for the waste lines. 

On another note, if I may, the pad you mentioned you were thinking of installing – when forming it out, I strongly recommend that where the tires track on the concrete, you pour the tracks at 6” deep, adding rebar to minimize the possibility of damaging the concrete (cracking) due to the weight of the motor home. The remainder of the slab can be 4”. 

Another thing you can do is install divots in the concrete where you know you want the coach to stop after returning from a trip. This way, when you enter and you hit the divot you know the coach is where you want it without getting in and out to check, or having someone guiding you. 

This sounds like a fun project 

Underground garage


I am a Board of Director member at an association in Van Nuys, though I read your article weekly online, as I have moved from Santa Clarita but always loved your article. 

We have an underground garage, and quite an extensive amount of hardscape on the property, with many area drains. 

I know you’ve written previously about cleaning area drains and keeping the sewer lines in the garage clear. 

Can you please tell me how often these items need to be done in order to keep things maintained and functioning properly? 

This property seems to have been let go some, though I believe the bones are good and it has potential to be beautiful. 

It seems as though the new BOD has good business sense, and we are all willing to do what it takes to get it back up to a high-end property. 

If you could elaborate on the major maintenance items and when they should be done and why, I would greatly appreciate it. 

I am confident that with your guidance in this way, we will have great tools to proceed with our goals. Thank you, Robert, for your expert advice weekly. -Roger C. 


You ask great questions. It’s nice to see that a new BOD is assembled and ready to do the right thing for your property. 

Lack of maintenance is something that is a common factor at many properties. There are so many folks out there that will spend more money on their cars then they will for the single biggest investment of their lives – their homes. 

When a BOD is of this mindset, properties fail in fast form and it is a difficult, and sometimes very costly, recovery from negligence. 

The horizontal lines, which are your sewer lines that are overhead in your garage, would be one of my first items to address. 

I recommend that horizontal lines be cleaned with a jetter, annually. These lines are the “highway” for all of the sewage waste for your building. The waste makes its way down the vertical lines and into the horizontals, and out to the sewer. 

The verticals have the advantage of gravity, much of what goes down flows well. The horizontals are usually cast iron and over time, as they build up, they can “grab” anything that is not liquid or human solids, such as feminine products or other items that are flushed. 

When this happens, you start the damn effect. You can have so much buildup, even in a situation like this, where enough flows through to not cause a problem…until it causes a problem. 

Well, what’s going to happen when that horizontal ends up completely impacted? Where does the waste go? It backs up in the vertical lines, and as we all know, “water” (in this case, sewage) takes the path of least resistance. This means that the sewage is going to find its way out the nearest openings to the blockage, likely a shower, tub, sink, or toilet (or all of them) and into someone’s unit. 

I’ve seen it more times that I care to think about, and we deal with this in my business often. This ends up being an emergency call and the costs involved are astronomical, as everything needs to be sanitized and very often, changed out completely depending on the severity of the overflow and the duration the sewage was flowing/sitting. 

The area drains are also very important to clear annually.

I recommend that these be done after leaves have fallen and all debris has been removed from the property, but prior to the first rains of the season. 

This same timeline applies to cleaning the rooftop gutters and downspouts. Wait until the leaves have fallen, and get the gutters not only cleared, but cleaned and make sure that whoever you hire, follows through and does the same with the downspouts. 

Debris can become impacted in the downspouts, causing backups to the gutters, and eventually overflowing, possibly causing roof and other leaks. 

Anything that aids in water flow on your property, you’ll want to be sure it is cleared annually and that it is tested for proper flow. 

Good looking out for your property, and good luck getting things back under control.

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