By Bernardy Lighting • June 2026
Core drilled low voltage lights have become our single most requested upgrade across DFW. If you’ve seen a home where the soffit downlights look like they’re part of the original architecture — no surface-mounted cans, no visible conduit, no brackets or straps, just a clean flush LED lens in the eave — that’s core drilling. Here’s what it is, why it’s better than surface mounting, how the process works, and which homes are the best candidates.
What Is Core Drilling for Outdoor Lighting?
Core drilling is the process of drilling a precise hole through your home’s soffit or eave material — typically vinyl, aluminum, or wood — to recess a low-voltage LED fixture flush with the surface. Instead of strapping a surface-mount fixture to the outside of the soffit (where it’s exposed to weather, visible from the ground, and prone to water infiltration at mounting points), we drill through the soffit, insert a purpose-built recessed housing, and route the wire back through the soffit cavity to the transformer. The fixture face sits flush with the soffit surface. From the ground, all you see is a small LED lens — identical to what you’d see on an indoor recessed can in your kitchen, but weatherproofed for exterior use. The effect from the street is architecturally clean in a way that surface-mount hardware simply can’t match.
Why Core Drilling Is Better Than Surface Mounting
No Surface Hardware
Surface-mount soffit fixtures require external straps, brackets, or saddles to hold them against the soffit face. These metal-to-metal contact points collect water and create corrosion pathways that, over 3–7 years depending upon package selection, cause rust staining, bracket failure, and fixture sagging. In DFW’s combination of humidity, UV, and temperature swings, surface hardware ages visibly and quickly. Core-drilled fixtures have zero surface hardware — the only thing visible is the flush lens, and the entire electrical connection lives inside the protected soffit cavity.
Cleaner Appearance
The visual difference is stark. Surface-mount fixtures read as “add-on” — even high-quality ones look like something attached to the house rather than part of it. Core-drilled fixtures read as architectural. Homebuyers notice the difference. Neighbors notice the difference. The “wow” response we get from clients when they see their finished core-drilled install is consistently stronger than for any other fixture type we install.
Better Waterproofing
The soffit cavity is a naturally protected space. Wire routed through the soffit interior is shielded from direct weather exposure. The hole itself is sealed with a weatherproof gasket at the fixture housing. This approach keeps the electrical connection points in a protected environment rather than exposed to direct rain, which is the primary cause of fixture failure in surface-mounted installations.
No Wire Exposed on Exterior
Surface-mount soffit lighting almost always requires some wire routing along the exterior soffit face or down the fascia to reach the transformer. Core-drilled installations route 100% of the wire inside the soffit cavity — completely hidden, completely protected, and invisible from any exterior viewing angle. The result looks like the lighting was built into the house when it was constructed.
How the Installation Process Works
Step 1 — Soffit assessment: We examine the soffit material (vinyl, aluminum, or wood) and cavity depth to confirm core drilling is feasible and to determine the correct drill bit size. Most residential soffits in DFW are vinyl — these drill cleanly with the right coring bit. Aluminum soffits require a different bit and additional care. Some homes with sealed or blocked soffit cavities require alternate routing — we assess this before quoting.
Step 2 — Layout and spacing: We measure and mark fixture locations based on the eave length and the desired spacing (typically every 6–8 feet, adjusted for window, corner, and architectural element placement). Correct spacing is critical — fixtures placed too close create hot spots; too far apart leaves dark zones between fixtures.
Step 3 — Drilling: We drill through the soffit face with a hole saw sized for the specific fixture housing. For a standard vinyl soffit, this takes about 30 seconds per hole with the right equipment. The drill bit creates a clean, round hole that the fixture housing seats into precisely.
Step 4 — Wire routing: We route low-voltage wire through the soffit cavity between fixture locations and back to the transformer location. On homes with accessible attic entry above the soffit cavity, this goes quickly. On homes with blocked or limited cavity access, we use a fish tape through the drilled holes — time-consuming but still completely hidden when finished.
Step 5 — Fixture installation and weatherproofing: The fixture housing seats into the drilled hole and is secured to the soffit. A weatherproof gasket seals the perimeter of the hole against moisture infiltration. Wire connects inside the housing, the LED module snaps in, and the face trim locks in place.
Step 6 — Connection and testing: All fixtures are wired back to the transformer, connections are made, and the system is tested at night for coverage, brightness, and aiming. Core-drilled fixtures are typically fixed-aim, but the lens housing can be rotated in some models for minor adjustment.
Cost vs. Surface Mount
Project pricing is quoted for the current scope, equipment, access, and site conditions. New installation projects generally begin at $2,000.
Which Homes Are the Best Candidates?
Core drilling works best on homes with:
- Vinyl or aluminum soffits — The most common in DFW residential construction. Drill cleanly and cleanly.
- Accessible soffit cavities — 3+ inches of depth for fixture housing. Most standard residential soffits qualify.
- Brick or stone facades — The architectural clean look of core-drilled fixtures is especially compelling on masonry — the warm light on textured brick with no visible hardware is a premium look.
- New construction or recently renovated — Perfect time to add soffit lighting before landscaping is fully established.
Core drilling is challenging on homes with very shallow soffits (under 2.5 inches), completely sealed and inaccessible soffit cavities, or homes with asbestos-containing soffit materials (pre-1980 construction in some cases — we always assess before drilling). We’ll tell you upfront if surface mounting is the better option for your specific situation.
Frequently Asked Questions
Will drilling through the soffit affect my home’s weather sealing?
No, when done correctly. The fixture housing seals the hole at the soffit face with a weatherproof gasket. The installation actually creates a sealed penetration rather than a gap — equivalent to how an outdoor HVAC penetration is handled. We’ve never had a water intrusion complaint from a core-drilled soffit installation.
Can core-drilled fixtures be aimed or adjusted after installation?
Most core-drilled soffit fixtures are fixed-aim straight down, which is the correct angle for washing a facade. Some models have adjustable-aim LED modules inside the housing that allow 15–20 degrees of tilt. We select the appropriate fixture for the application — on most standard DFW eaves, the fixed straight-down aim is ideal.
How long does core drilling installation take versus surface mount?
A standard 40–60 foot eave with 6–8 core-drilled fixtures adds approximately 1.5–2.5 hours to an installation compared to surface mounting the same number of fixtures. For most homeowners, this extra time is completely worth the visual and longevity improvement. Total install day length for core-drilled soffit lighting only: typically 3–5 hours for a single-story home.
Ready to upgrade your outdoor lighting?
Bernardy Lighting serves all of DFW. Free consultations, professional installs, 3-, 5-, or 7-year Bernardy Lighting system warranty covering qualifying materials and our labor/workmanship, depending on the selected package and subject to the written warranty terms.
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