We’re doing a pretty major backyard reno that includes tearing up the entire existing yard and adding several retaining walls. We’re already at the top end of our budget, and can’t afford to wire the yard for electricity now. However, we were thinking we should at least lay a conduit from the house to the back of the yard now, before the retaining walls are built, so that installing cables later won’t be such a major project.
Does this make sense before we have a final lighting plan, or is it a waste of time?
This absolutely makes sense! This is a perfect solution to your problem.
I would personally recommend running multiple conduits of a decent diameter from a place near your electrical panel that you will use to power the backyard to multiple places in your yard so that you have options in the future (lighting, irrigation, cooking, fountains, etc.)
I would also recommend having your landscaper install the conduits because he/she will know the code as far as the depth of the conduits under the dirt. He/she can also make sure to include pull string in the conduits for the future electrician to use to pull his/her wires.
Carl,
First, make sure to verify everything you do with your local inspector. That being said…
Not only does this make sense, but it is exactly how the utility company in your city does it. You will want to be careful of a few things.
#1 Make sure you have a way to pull the wire through the conduit effectively after it’s in the ground. The biggest problem we see is the connection between the pulling rope and the wire becomes too big to pull through the sweeps. So try that pulling that connection through a sweep before putting in in the ground to see that it fits.
#2 Compact the ground under the conduit so that it won’t shift and break before you pull the wire. This is very common and can make for a long day.
#3 Try to surround the conduit with sand. This will keep large rocks etc. from damaging your conduit in the shifting ground.
#4 Cover both ends of the conduit to keep water out prior to pulling. After pulling the wire, be sure to use proper, engineered connections that are watertight.
Absolutely bury the conduit. Code requires 18" of cover (to top of conduit, not bottom of trench) unless there will be no more than a 30A circuit or a couple 20A circuits, in which case only 12" of cover is required. Use PVC to save money, but apply a good cement, like Christy’s Red Hot Blue Glue. Where you turn up out of the ground, SF generally requires rigid steel. You might get by with PVC if you make the whole run with schedule 80 (heavy wall). Be sure to size the conduit correctly for the circuit/s you need, and if using schedule 80 go another size up (heavy wall reduces interior).
If you are doing a major backyard renovation now that includes tearing up the entire existing yard there will not be a better time to lay the conduit! If you do not want to damage your lawn later and pay more money, do it now. Of course having a lighting plan is very important before you lay any conduit but a good thing is it does not cost anything! We would advise you to talk to a licensed electrician now to get some idea about the cost. Buying the light fixtures and wiring could be done at a later time if the electrician secures the conduit properly.
