Globe String Lights: G40 vs G50 Sizes and Best Uses

Round bulbs strung across a patio are one of the quickest ways to make a backyard feel like a finished outdoor room. Globe string lights come in several bulb sizes, and the size you choose changes the whole look: small bulbs read as a delicate sparkle, while big ones feel like a café or beer garden. Picking the wrong size is the most common regret, usually because the bulbs look very different overhead than they do in a product photo.

The short answer for most patios is this: G40 bulbs suit decks, pergolas, and dining areas under about 20 feet across, while G50 bulbs suit larger yards, higher mounting points, and commercial-style spans. G30 bulbs work best close to eye level on railings, trees, and balconies.

This guide explains what the G numbers mean, how shatterproof compares to glass, how spacing affects brightness, and how to set up a plug-in strand safely outdoors.

What the G Numbers Mean for Globe String Lights

Lighting manufacturers name bulbs by shape and diameter. The “G” stands for globe, and the number is the diameter in eighths of an inch in the traditional system, though most outdoor string light sellers now simply use it as millimeters. Either way, the practical takeaway for globe string lights is that a bigger number means a bigger bulb.

A half-inch difference sounds minor until the bulbs are hanging 10 feet overhead. G50 bulbs are clearly visible from across a yard, while G30 bulbs nearly disappear at that distance and look best within arm’s reach.

G40 vs G50: Which Size Fits Your Space

When G40 Makes Sense

G40 string lights are the default choice for residential patios. They are large enough to look intentional from the house, small enough not to overwhelm a modest deck, and they are the most widely available size, so replacement bulbs are easy to find. If you are zigzagging lights over a 12-by-16-foot deck or wrapping a pergola, G40 is usually right.

When G50 Makes Sense

G50 bulbs shine over wide lawns, poolside areas, and spans hung from 12 feet or higher. They throw a bit more light per bulb, and their scale matches bigger outdoor spaces. They also carry more wind load and weight, so long runs almost always need a guide wire.

Where G30 Still Wins

G30 strands are ideal for wrapping tree trunks, lining balcony railings, or decorating a smaller covered porch where the bulbs sit close to where people sit. They also look good indoors in bedrooms and dorm rooms.

Shatterproof vs Glass Bulbs

Classic glass globes have a crisp sparkle and hold up well to sun without yellowing. The trade-off is fragility: a strand that gets knocked by a ladder, a thrown ball, or a heavy wind gust can drop broken glass onto a patio where people walk barefoot.

Shatterproof bulbs are made from plastic or acrylic, weigh less, and bounce instead of breaking. Early versions looked cloudy, but many current shatterproof globes are close to glass in clarity. They are the better choice around pools, play areas, and anywhere pets roam. Glass still has an edge for long-term UV resistance and that slightly brighter, cleaner look.

If you choose glass, handle bulbs with work gloves and safety glasses when installing or replacing them. Never force a stuck bulb by twisting hard or flexing it against the socket, and never tap a bulb against anything to “seat” it. Sweep broken glass with a broom and dustpan, then pick up fine shards with a damp paper towel rather than bare hands.

Bulb Spacing, Brightness, and Color Options

Spacing controls both brightness and style. Most strands place bulbs every 12 inches, which gives an even, well-lit canopy. Some budget strands space them every 24 inches; that saves money but can look sparse on short spans. For a 25-foot strand, 12-inch spacing means about 25 bulbs, while 24-inch spacing gives roughly 12.

Brightness comes down to bulb wattage and color temperature. LED globe bulbs typically draw well under 1 watt each, which keeps energy use low even on long runs. Warm white around 2,200K to 2,700K creates the classic amber glow; 3,000K reads cleaner and slightly brighter. Colored patio lights with multicolor or RGB bulbs add a festive feel, and many smart strands let you switch between warm white and color from a phone app.

• Warm white (2,200K to 2,700K): relaxed dining and entertaining.
• Soft white (3,000K): more usable light for cooking or games.
• Multicolor or RGB: parties, holidays, and kids’ spaces.

Step-by-Step: Planning and Hanging Globe Lights Outdoors

1. Measure and sketch. Map the spans between anchor points and add about 10 percent for drape. Note where the nearest outdoor outlet sits.
2. Check the connection limit. Every plug-in strand lists a maximum number of strands you can link end to end. Stay under that number with room to spare.
3. Install anchors. Use screw hooks into solid wood fascia, posts, or beams. Attach to framing, not just vinyl siding or thin trim.
4. Run a guide wire for long spans. For spans over about 15 to 20 feet, stretch a vinyl-coated steel cable with a turnbuckle and clip the strand to it every couple of feet.
5. Hang and test. Hang the strand unplugged, then plug in to test once everything is secure.

Work from a stable ladder on level ground and avoid reaching overhead while holding a heavy coil. For second-story eaves or roofline spans, hiring a pro or using a scaffold is safer than stretching off a ladder.

Electrical Safety for Plug-In Strands

Most globe strands plug into a standard outlet, so a few basic rules keep them safe. Buy strands marked for outdoor use and listed by a recognized testing lab, such as UL or ETL. Plug them into a GFCI-protected outdoor outlet with a weatherproof in-use cover, and use only outdoor-rated extension cords sized for the load. Keep plug connections off the ground and away from puddles, and wrap junctions with a weatherproof connector cover.

Before swapping a bulb, unplug the strand. If the lights are wired into a switched circuit, turn off the breaker and confirm power is off with a non-contact voltage tester before touching sockets. Plug-in strands are a DIY-friendly project, but adding a new outdoor outlet, a hardwired switch, or a dedicated circuit is a job for a licensed electrician, who can pull the permit and make sure the work meets local code. Some homeowners use low-voltage strands powered by an outdoor-rated transformer; those carry less shock risk, but the transformer itself still plugs into a GFCI outlet.

Troubleshooting Common Globe Light Issues

One bulb out, rest working. Most modern strands are wired in parallel, so a single dead bulb does not kill the string. Unplug, then replace it with a matching bulb.

Whole strand dark. Check the GFCI outlet first; it may have tripped from moisture. Then check the small fuses inside the male plug, which some strands include.

Flickering. Loose bulbs, moisture in a socket, or an incompatible dimmer are the usual causes. Reseat bulbs gently and use a dimmer rated for the strand.

Sagging lines. Add a guide wire or intermediate support posts. Planter-based poles work well on patios without trees or walls.

Cost Ranges

A 25-foot G40 strand with shatterproof LED bulbs generally sits in the low-to-mid double digits, and 48-foot heavy-duty strands cost more. G50 strands run somewhat higher per foot. Smart color-changing strands carry a premium. Budget a bit extra for a guide wire kit, hooks, and connector covers. Professional installation varies widely by span height and complexity, with simple single-story jobs on the lower end and multi-story or pole-mounted systems higher.

For most homeowners, G40 globe string lights with shatterproof bulbs and 12-inch spacing hit the sweet spot of look, durability, and price. Step up to G50 for large yards and high spans, and save G30 for close-up accents.