When it comes to installing exterior lighting for your home, one of the key decisions you’ll need to make is whether or not you need a mounting block. A mounting block is a sturdy base that provides extra support and stability for exterior light fixtures. In this article, we’ll go over when you need a mounting block and when you may be able to get by without one.
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What is a Lighting Mounting Block?
A lighting mounting block is a sturdy platform that is installed between the exterior wall surface and the light fixture. It creates a solid, secure connection point for the light. Mounting blocks are commonly made of metal or plastic and feature holes where the light fixture is bolted into place.
The main purpose of a mounting block is to provide extra strength and durability for the light fixture. Exterior lighting elements are exposed to the outdoor elements such as rain, wind, and changing temperatures. A mounting block helps ensure the fixture remains securely attached to the wall over years of use.
When Do You Need a Mounting Block?
Here are some of the main situations when you should install a mounting block for exterior lighting:
- Heavy light fixtures – If the light fixture is large, heavy, or projects out significantly from the wall, a mounting block helps support the weight and leverage forces.
- Masonry walls – Mounting blocks provide a strong, durable attachment point for masonry walls like brick, concrete, stucco, and stone.
- Vibration-prone areas – In locations exposed to vibrations from nearby roads, machinery, or other sources, a mounting block helps stabilize the fixture.
- Frequent maintenance – If the light fixture will need to be accessed frequently for bulb changes and cleaning, a mounting block allows simpler removal and reinstallation.
- Junction box issues – If there is no existing exterior junction box or the junction box is corroded or damaged, a mounting block can provide the stable attachment point needed.
The general rule of thumb is that for large, heavy, or frequently accessed exterior lights, you should install a mounting block. It provides the durability and strength needed for long-term use.
When Can You Go Without a Mounting Block?
For some smaller, lightweight exterior lighting fixtures, you may be able to get by without a mounting block. Here are some instances when it may be acceptable to mount the light directly to the wall:
- Small, lightweight fixtures – Low profile or smaller lights that do not project far from the wall may not require reinforcement.
- Protected locations – Fixtures under porches, eaves, or other covered spots are less exposed to elements and may not need a mounting block.
- Temporary use – For exterior lights used seasonally or as a temporary solution, direct wall mounting may suffice.
- Solid wood walls – Secure fastening directly into a solid wood stud or wall structure may provide enough support.
- Pre-existing junction box – If there is already a sturdy exterior junction box in place, you may be able to mount the fixture directly to it.
However, even for smaller fixtures it is often a good idea to install a mounting block if possible. It provides extra stability and strength that helps the light last longer. The minimal extra effort during installation is usually worth it for the long-term benefits.
Mounting Block Materials
Mounting blocks are available in a variety of different materials:
- Plastic – Plastic mounting blocks are inexpensive and easy to install. However, they are the least durable option over the long term.
- Steel – Steel mounting blocks provide strength and durability. However, steel can rust over time when exposed to the elements.
- Aluminum – Aluminum mounting blocks offer corrosion resistance while still providing substantial strength.
- Reinforced plastic – Some plastic mounting blocks feature fiberglass reinforcement for added durability while limiting weight.
- Polycarbonate – Polycarbonate plastic mounting blocks withstand weathering better than standard plastic while still being lightweight.
For most homes, an aluminum or polycarbonate mounting block often provides the best solution. Avoid cheaper unreinforced plastic blocks for important exterior lighting applications.
Mounting Block Fasteners
Mounting blocks feature pre-drilled holes for mounting the light fixture. Here are some of the common fastener options:
- Machine screws – Machine screws with washers and nuts allow tool-free mounting block installation. They also make light fixture removal simple for maintenance.
- Lag screws – Lag screws bite securely into wood surfaces for a durable stud connection.
- Bolts with anchors – Bolts paired with concrete anchors or masonry drill-in anchors provide solid masonry mounting.
- Self-tapping screws – Self-tapping screws drill their own thread pattern into plastic mounting blocks for quick attachment.
Always choose exterior-rated, corrosion-resistant fasteners. Stainless steel hardware is ideal for coastal areas. The mounting block fasteners used should match the wall material – brick, concrete, wood, etc.
Mounting Block Size
Mounting blocks come in a range of different sizes to suit various exterior lighting fixtures. Choosing the right size helps ensure the block can adequately support the fixture. Some key measurements to consider include:
- Base diameter – A larger base diameter provides more stability. It should be scaled appropriately for the light’s size and leverage forces.
- Height/depth – The mounting block height ranges from low-profile slim models to thicker blocks that project out farther from the wall.
- Light fixture bracket – The block should be large enough to fully support the light’s back bracket or mounting plate.
- Junction box – If wiring connections will be made within the block, it must be deep enough to house the junction box.
Taking some measurements of your particular light fixture before choosing a mounting block will help identify the optimal size. The manufacturer’s recommendations can provide helpful guidance as well.
Mounting Block Installation
Here is an overview of the main steps involved in properly installing a mounting block:
- Choose a suitable location – Pick an area of the wall that provides optimal light distribution and allows all electrical connections to be safely housed within the block if needed.
- Mark the position – Use a pencil or painters tape to mark the exact spot where the block will be installed.
- Drill pilot holes – Drill appropriately sized pilot holes for the fasteners that will secure the block. For masonry walls, use a hammer drill and masonry bit matched to the anchor size.
- Run wiring – Pull any necessary electrical wires through the mounting block. Leave some excess length for connections.
- Attach the block – Secure the block to the wall using the appropriate fasteners for the material. Tighten everything down snugly.
- Make connections – If needed, use wire nuts to connect the light wires within the block.
- Mount the light – Bolt the exterior light securely onto the mounting plate using the manufacturer’s instructions.
Pay attention to details like wall material, junction box placement, and fastener type during the installation process. Taking the time to properly mount the block will ensure your exterior light stays securely in place for years.
Conclusion
In summary, mounting blocks provide an invaluable reinforcement point for most permanent exterior lighting fixtures. The extra stability and durability they offer tends to make them a wise investment for the long haul. For heavy or frequently accessed lights, mounting blocks should basically always be used. In some select cases, smaller and more protected fixtures may be able to get by without one. But in general, take the time to do it right so your outdoor lights will stand the test of time.
| Mounting Block Material | Pros | Cons |
|---|---|---|
| Plastic | Inexpensive, easy to install | Less durable than other options |
| Steel | Very strong and durable | Can rust over time |
| Aluminum | Good strength, corrosion resistant | More expensive than plastic |
| Reinforced Plastic | Lightweight with added durability | Costs more than standard plastic |
| Polycarbonate | Withstands weather, UV resistant | Can become brittle over time |
Light Fixture Size and Mounting Block Needs
| Light Size | Projection Distance | Mounting Block Recommended? |
|---|---|---|
| Small accent light | 2 inches or less | Optional |
| Medium wall lantern | 4-6 inches | Recommended |
| Large hanging light | 12 inches or more | Strongly recommended |
| Heavy porch light | Any | Mandatory |
Exterior Wall Materials and Best Mounting Blocks
| Wall Material | Best Mounting Block |
|---|---|
| Wood | Plastic or aluminum with lag screws |
| Brick | Steel or aluminum with masonry anchors |
| Concrete | Steel or aluminum with tapcon concrete screws |
| Stucco | Plastic or aluminum with masonry anchors |
| Stone veneer | Steel or aluminum with masonry anchors |
| Siding | Plastic or aluminum with lag screws into studs |
As shown in the tables, the optimal mounting block fasteners and materials depend on factors like the light fixture size, wall materials, and projection distance from the wall. Consider all these elements when selecting and installing an exterior light mounting block. This will provide the fixture with the durable, long-lasting support it needs.
Some additional things to keep in mind when using mounting blocks for outdoor lights:
- For heavy fixtures, use extra large mounting blocks or install multiple blocks.
- Space blocks evenly to balance the weight of asymmetric light designs.
- Shim underneath uneven wall surfaces so blocks mount flush.
- Caulk around the blocks to create a waterproof seal.
- Make all electrical connections watertight within enclosed junction boxes.
Properly installing mounting blocks takes a bit more time upfront. But putting in that extra effort will pay off for many years down the road through superior stability. Just remember that “better safe than sorry” rule when it comes to providing durable support for permanent exterior lighting fixtures. The right mounting block installed correctly keeps lights shining bright night after night.