Underground conduits to garage and shed

Two years ago we dug and laid three conduits from the house to the garage, and from the garage to the shed. Primarily to get more power to the garage — and any power to the shed.

I used the opportunity to put in an additional conduit for fiber, and lots of conduits from the main switch board down into the basement.

Introduction

We’ve had power in the garage since we moved in, but only single phase 230V 16A. That’s plenty for a few lights and a garage door opener — but with an EV charger, power tools, and future lights, heat, and appliances in the shed… It’s not enough.

I’m also quite obsessed with our outdoor lights, I hate when they don’t come on at exactly the same time. Everything should be synchronized, and controlled from one central location — the main switch board. So one conduits will be used for outdoor lights.

For fiber; I want 10 Gbit between the house and garage, and garage and shed (we’re currently working on refurbishing the shed). But first; the underground conduits 👇

Underground conduits

So; we a landscaper dug a trench between the house and garage, and garage and shed.

I’ve previously dug a trench between the house and garage, and it wasn’t much fun. So this time we paid someone else to do it 😎

Our electrician put down three conduits:

• 50 mm for three phase 230V 40A between house and garage
  • 25 mm for power between the garage and shed
• 25 mm for power to outdoor lights
• 25 mm for future fiber

Once the electrician was done — the landscaper came back and filled in the trench and put the top layer of grass, and pavers, back.

Power cables

Time to pull some cables 👷‍♂️ The trench ends under our front door, where the internet fiber and multiple network runs already enter the basement.

On the other side is the basement stairwell, which has a nice cavity behind a wooden beam resting on the foundation. I’m already using this “hidden space” for multiple network conduits.

Sharing a wall with the basement stairwell — is the main switch board (#1 on the layout). The new cables and conduits will enter at #2.

We (the electrician and I) removed the shelf and wooden beam, then drilled through the foundation in a downward angle.

We had to open the wall underneath the main switch board, and drill through into the basement stairwell. We used a 25 mm conduit for the power cable (4x10mm²) and 20 mm conduit for the outdoor lights (3x2.5mm²).

I used this opportunity to pull multiple conduits for future use, you can never have enough unused conduits — more on that later…

The two conduits to the garage, used for power, was terminated outside — while the one for future fiber was pulled all the way into the basement.

Same thing by the garage; conduits for power was terminated outside and only the cables going in, while the one for fiber went into the garage.

The power cables in the garage goes into the sub panel we have have there.

Conduits to basement

As I already mentioned; I used the opportunity, with the wall open, to pull lots of additional conduits from the main switch board into the basement.

And to install a new power outlet and hidden power to a lamp in the basement stairwell.

Five 16mm and one 20mm conduits, in addition to the ones needed for the garage. Future usage FTW! 🤘

I had some cable duct left over from my previous network runs, many of which also ends up in the basement stairwell. I bought an end-cap, and made an opening between the two ducts.

Then routed the new conduits into the new, and topmost, cable duct. With the exception of a single conduits, which ends in the cavity behind the wooden beam.

Here I am still waiting for the electrician to wire up the new power outlet, and hidden supply to the lamp.

With the new conduits in place, the wooden beam and shelf was reinstalled. And all the shoes put back.

Spare conduits! 🤤 The big 25mm conduit in the bottom cable duct goes all the way to the garage.

The new outlet and supply to the lamp was installed 👍 The white thing with the antenna is a Zigbee router from TubesZB.

Covering up

Time to cover things up. Having some sort of protective cover for cables and conduits as they come out of the ground is important, and required by law if dealing with power cables (at least here in Norway).

With a total of six conduits coming up by the garage — I struggled to find a solution that looked halfway decent. I ended up having a custom “cover” made by a tinsmith.

The three conduits on the house were covered by a 68mm wide capping steel channel. I cut and bended it to get it over the concrete footing by the ground.

I cut and fitted a chipboard to cover the opening underneath the main switch board. I still need to fill in the gaps and paint it. But that can wait until we redo the entire entryway.

To the shed

Three conduits were laid between the garage and shed — also for power, outdoor lights, and fiber. 3x2.5mm2 was pulled for power and outdoor lights, in separate conduits.

The fiber will have to wait until we have completed the shed refurbishment, and have fiber connection between the house and garage.

Getting the new conduits into the shed was combined with rebuilding the exterior wall…

Making them nice and hidden 👍 I’m going to install one, or two, recessed cabinet inside the shed — where the conduits will be terminated.

When the winter is over; I will install some protection around the exposed conduits between the wall and ground.

What about the fiber!?

As I am writing this post, I have ready pulled a single mode fiber from the house to the garage. There will be a blog post about that in the not-so-distant future.

🖖