How to Make Exterior Light Mounting Block? [Easy Steps]

Exterior lights don’t only enhance the beauty of your house, but it also increases safety. As the lights will be set outside, a mounting block is a must for some reasons.

Mounting blocks are available in the shops but most of the time they have fittings issues. It’s better if you can make your own blocks according to the nature of your siding.

Today I am going to show you how you can make a mounting block and install your exterior light on that.

What is a Mounting Block?

A mounting block is a piece of structure that is used to hang or set electrical equipment like lights, fans, and many more to the side of a building or wall.

The mounting block stays in the middle of the electrical equipment and the outlet or sheathing. It gives a stable surface and also works as a protector of the siding.

Types of Mounting Blocks

You might be wondering, why on earth I am telling you all this? Well, before you move on and start making a block and installing it, these little things will help you. 

There are generally two types of electrical mounting blocks for exterior lights:

  • Built-in wiring box. (These are PVC mounting blocks. you can either buy it or comes with the light set sometimes.)
  • Blocks with pre-cut gaps or whole. The gap is for allowing the wire to pass through.

Importance of Mounting Blocks

Exterior lights are heavier than usual lamps. When you directly set those exterior lights on the siding, it pulls the vinyl exterior downwards.

Though the vinyl exteriors are strong they might not be strong enough to hold on to that pulling. It can break or wrap due to the heavy weight and cost you some bucks to repair or re-install them.

When you install the light with a mounting block, the block holds the pressure instead of the vinyl siding.

I can show you two more reasons why the mounting block is important;

  • When you install the light directly, it will create a gap between the vinyl siding gaps. Moisture can cause mold and rot. Pests can make the gaps their safe houses.
  • The only solution to these problems is using mounting blocks to install exterior lights. Now, let’s move forward to the procedure of making a mounting block.

Tools Required

You will need some instruments to make a mounting block for your exterior lights. Here they are:

a) Exterior screws

b) Screw gun

c) Mounting block set (If you have a built-in one)

d) Wooden block/PVC board

e) Utility knife

f) Siding tool

g) Pencil

h) Oscillating cutting tool

i) Measuring tape

j) Cable connector

Light Mounting Block

Steps to Make an Exterior Light Mounting block

To describe the making procedure, I will take you through two simple steps;

  • Preparing the block, and
  • Installing the block (both handmade & built-in ones)

Let’s start the procedure:

Preparing the block

It might hear a bit difficult, but when you will follow these tips, it will become a lot easier:


Take a piece of wood or PVC and cut it into a square shape. The size will be approximately a little larger than the back part of your exterior light. If it doesn’t have enough space, it will be difficult to attach the screws.

When you take measurements of the block, make sure the top and the bottom edge of the wood are aligned with the siding line ends.


Now make a hole in the middle of the mounting piece. The whole will be in the size of the outlet box.


Now it’s time for making some screw holes. Mark four points on the wood/PVC at opposite corners.


Make a notch at the four sides of the block. This will help the block to fit perfectly with the siding edges.


Now place the mounting plate over the block and draw pilot holes with a pencil. Pilot holes will be there where you are going to set the mounting plate.


Attach the mounting plate with a screw gun. The hole of the mounting plate should align perfectly with the hole on the block.

Now, the mounting block is ready and you are ready to install it.

Installing the Mounting Block

You have our mounting block for the exterior light ready to be installed. Here you will start our next step. When you have a built-in mounting block or mounting block set, you need to start from this point:

  • Choose the spot where the outlet is or where you want to set the exterior light.
  • Now, hold the mounting block on the selected spot of the siding. Make an outline with a pencil over the siding.
  • Though will not have to cut the whole siding, you must cut a part of the vinyl siding. You can use a utility knife for cutting. But an oscillating tool will give you a precise and quick result.
  • Take your time and start cutting through the outline you draw. Keep it slow and careful. The mounting block must fit perfectly in the gap. Once the cutting is done, put the block in the gap to check the fitting.
  • Now it’s time for connecting the wear to the outlet.
  • This step is for the wooden mounting block that you made earlier; hold the block on the wall while the mounting plate is facing toward you. Now, attach it to the wall by screwing the four corners with a screw gun.
  • You can now seal the small gaps between the block and the vinyl siding with sealers. It will protect lights from water and pests
  • You can now set the exterior light to the mounting block. You can color the wooden block to match it with the siding.
  • If you have a built-in mounting block, push the wire through the cable connector and screw the block to the sheathing. Instead of screwing the block, you can slip the sides of the block inside the siding.

I would not recommend this as you have to fasten the block with house wrap. It’s not a safe process when you have a heavy exterior light. Screwing the built-in mounting block is a lot safer and easier.

Note: Don’t forget to take proper safety measures. Wear protective glasses while drilling and working with oscillating tools. Don’t forget to turn off the circuit breaker while giving electrical connections.


Making and installing an exterior light mounting block is not a very hard task to do. A DIYer with basic knowledge can easily do it with proper tools and guidelines.

All you need to do is follow the above instructions and do it with steady hands. So, what are you waiting for? Start making your house more beautiful by putting on some exterior lights. Making a mounting block is not that hard anymore.

About The Author

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Written by Shimul
Hi, I'm Shimul, the founder of Trendy Outdoor. I'm excited about sharing the latest outdoor living trends with you. My goal is to provide you with up-to-date information that will help make your outdoor space stylish and enjoyable. Read About Me More । Follow on Facebook

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