Okay, let's break down recessed lighting for a 20' high finished barn ceiling. This is a challenging scenario, and a proper design is crucial for good lighting. Here's what to consider and what has worked for me and others

Understanding the Challenge
Height

20' is very high for residential-style recessed cans. This means you'll need high-output LEDs and narrow beam angles to effectively get light down to the usable space.

Finished Ceiling

Since the ceiling is finished, accessibility for wiring and installation is more complex. Careful planning is essential.

Barn Environment

Is the barn insulated and climate-controlled? Temperature and humidity can affect the lifespan of LED fixtures. Are there potential hazards like dust or moisture?

Purpose

What is the barn used for? This greatly influences the required light level. Is it for storage, workshop activities, events, or something else?

Lumens and LED Trim Kits Lumens Needed

This is where it gets tricky. Lumens are a measure of total light output. Because of the height, you will need a lot more lumens per fixture than you would in a typical 8-10 foot ceiling. There is no single answer without knowing the barn's use and the desired foot-candle level at the work surface.

Available Lumens in LED Trim Kits

LED trim kits can range widely in lumen output. You can find kits anywhere from 600-1600 lumens (or even more) per fixture. The important number here is to compare center beam candle power to focus the most light directly below the fixture.



Common residential 6" recessed LED trims

600-900 lumens (generally NOT sufficient for your application unless you use a lot of them).

Higher-output 6" or 4" trims

1000-1600+ lumens. These are more likely to be suitable, especially if you choose a narrower beam angle. Look for LED trims specifically designed for high ceilings or commercial applications.

What Has Worked for Me and OthersHere's a combination of approaches that tend to be successful for high ceilings:1.

Prioritize Beam Angle over Absolute Lumen Output

A wider beam angle (e.g., 60 degrees) spreads the light out more, but it loses intensity over distance. At 20 feet, a wide beam will result in a lot of light lost to the upper areas and not enough at the floor.

Choose a NARROWER beam angle (25-40 degrees) to concentrate the light directly downwards. This will maximize the light you get at the floor level for a given lumen output. Manufacturers should publish beam angle specs. In order to maintain a good spread of light, place fixtures closer together when using narrower beam angles.2.

High-Output LED Options (Commercial Grade)



Consider commercial-grade recessed lighting

Instead of relying on residential-style trims, look at fixtures designed for commercial spaces with high ceilings. These often have: Better heat dissipation (crucial for longevity). Higher lumen output. More precise optics for directing light.

High bay LED lighting

These are designed for industrial spaces. They can come as recessed or pendant mounted. They come in a variety of shapes and sizes.3.

Supplemental Lighting



Track Lighting

Install track lighting to supplement the recessed cans. This allows for adjustable light direction, making it ideal for task lighting or highlighting specific areas.

Pendant Lighting

Consider pendant lights over work areas or islands. These can provide focused illumination.4.

Placement and Spacing (Crucial!)

Closer Spacing

With high ceilings and narrower beam angles, closer spacing is essential. A common rule of thumb is to space recessed lights no further apart than the ceiling height divided by two (or even closer). For a 20' ceiling, that would be 10' or less, and perhaps even 8' or less depending on the specific fixtures and desired light level.

Grid Pattern

A grid pattern provides the most even light distribution.

Consider the room's shape and function

Place lights strategically based on how the space will be used.5.

Dimming



Install dimmers. This gives the customer flexibility to adjust the light level based on the task and time of day. Make sure the dimmers are compatible with the LED fixtures.6.

Color Temperature



Consider the color temperature (Kelvin). For a barn, a slightly warmer temperature (2700K-3000K) can create a more inviting atmosphere, while a cooler temperature (3500K-4000K) can be better for work areas.

Example Calculation (Rough)Let's say the customer wants roughly 30 foot-candles (a decent light level for general use) at the floor in a section of the barn.1.

Area

Let's say you're lighting a 10' x 10' area (100 sq ft).2.

Total Lumens Needed

Roughly, Foot-Candles x Area = Lumens. 30 fc x 100 sq ft = 3000 lumens needed for that area at the floor.3.

Lumens per Fixture (Considering Loss)

Due to the height, a significant portion of the lumens will be lost. Let's estimate a 50% loss (this is a guess and depends heavily on beam angle and fixture quality). To achieve 3000 lumens at the floor, you might need to start with 6000 lumens produced by the fixtures above.4.

Number of Fixtures

If you use fixtures that put out 1500 lumens each (a reasonable number for a high-output LED with a narrow beam angle), you would need about four fixtures in that 10' x 10' area. Important: This is a VERY simplified example. A professional lighting designer uses more complex calculations and takes into account surface reflectance, wall colors, and other factors.

Recommendations1.

Consult a Lighting Designer

For a space like this, strongly recommend that the customer consult with a qualified lighting designer. They can perform proper calculations and create a lighting plan that meets their specific needs.2.

Mockup

If possible, set up a temporary lighting mockup with a few fixtures before committing to the entire installation. This will allow the customer to see the light level and distribution.3.

Research and Compare

Don't just buy the cheapest LED trims you find. Research brands, read reviews, and compare specifications carefully. Look for fixtures with good warranties and reputable manufacturers.4.

Consider Installation Costs

Because of the height, installation can be more expensive. Factor this into the overall budget.5.

Electrical Capacity

Ensure the existing electrical system can handle the load of the new lighting. You may need to run additional circuits.

In SummaryLighting a 20' high barn ceiling with recessed cans is feasible, but it requires careful planning and the right equipment. Focus on high-output LEDs, narrow beam angles, close spacing, and consider supplemental lighting options. A professional lighting design is highly recommended to ensure optimal results. Flag for review