Foundation for Post Lights
A Construction Guide for DIYers
Anyone installing an outdoor post light needs a solid foundation, so the lantern can stand up to wind, frost, and other outdoor conditions for decades to come. Any DIYer can dig and pour the concrete foundation themselves. For this, you'll need:
- Shovel
- Spade
- Pickaxe
- Wheelbarrow
- Gravel
- Sand
- Cement
- Water
- Concrete mixer
- A plastic conduit pipe 600 to 1,000 mm long with a diameter of 30 to 50 mm
A licensed electrician must be brought in for the electrical connection.
Digging and Pouring the Foundation
Depending on the height of the lantern, you'll need a concrete foundation of (width A x width B x depth) 30 x 30 x 40 cm (for post lights up to about 2 m) up to 80 x 80 x 80 cm (for post lights of about 5 m). Dig a hole at the intended spot that is 10 to 30 cm deeper than the concrete foundation itself. Fill this extra depth with gravel and compact it. Then pour in pre-prepared reinforced concrete (250 kg of cement per cubic meter), embedding a plastic conduit pipe in the center of the foundation as you go. If a ground spike or mounting anchor is planned for the installation, embed that at the same time. The foundation then needs to cure for at least 14 days.
Pouring Concrete in Frost
If you're pouring concrete in freezing conditions, mix the concrete with warm water and heat it to around 70°C using a gas burner held in front of the mixer's opening. Once the pit is filled with the hot concrete and the surface has been smoothed, cover the foundation from above with a sheet of polystyrene so the surface doesn't freeze.
Running the Connection Cable
The connection cable must be an underground cable with a black PVC sheath (3 x 1.5 mm²). Feed the cable through the conduit pipe, leaving about ten centimeters protruding. Connecting the cable to the household electrical supply must be carried out by a licensed electrician in accordance with local regulations.
Mounting the Post Light on the Foundation
Once the foundation has been left to cure for 14 days, it's time to mount the post light. To do this, place the post base centered over the cable and pre-drill the mounting holes using a 6 mm masonry bit. Then remove the post base and enlarge the pre-drilled holes to match the size of the wall plugs. Insert the wall plugs, fasten the post base with the screws provided, and assembly of the column can begin.
