Composite gate installation · Galveston County, TX

Composite Gate Installation in Galveston County, TX

Walk and driveway gates faced with the same composite boards as your fence. What holds one up is hidden: a steel frame, a stiffened hinge post and adjustable hinges. Here is how the opening is sized, what hangs the gate, and the Galveston rules that shape it.

  • Reviewed Sept 27, 2026
  • Sources: Trex gate guides, Texas HSC §757, Galveston LDR
  • Opening planner
Double driveway gate with vertical wood boards set in a black steel frame over a solid metal lower panel, between a wood fence and the side of a gray house
Not composite: a Mustang double gate in Galveston with wood boards in a black steel frame. A composite gate is built the same way, frame first, with composite boards as the facing.
The short answer

A composite gate is a steel frame faced with composite boards. The boards give the look; the frame carries the load. In the published Trex Seclusions system that frame is 1¼ in square galvanized steel, welded and hidden behind the boards. The opening is sized to the panel: a standard single panel needs a 46¼ in opening (panel + 1⅞ in), and a double gate on two large panels needs 130½ in. The hinge post gets a steel stiffener, and posts go 30 in deep in 12 in holes, 2–3 days before the gate is hung.

1¼ inGalvanized steel frame inside a Trex Seclusions gate
46¼ inOpening for the standard single panel (panel + 1⅞ in)
12 ftWidest clear opening Trex lists for a double gate
30 inPost depth in 12 in holes; hinge post gets a steel stiffener

Sources: Trex Seclusions single and double gate installation guides (©2013); Trex Fencing gates page, checked Sept 27, 2026.

What a composite gate is, and what we install

Composite boards are wood fiber or flour mixed into plastic and extruded. The USDA Forest Products Laboratory notes they are less stiff than solid wood, so on their own they would sag across a gate. That is why composite gates are built frame-first: the manufacturer welds a steel frame, then faces it with the same boards and cap rail as the fence. Trex describes its Seclusions gate this way, with the frame “hidden behind the Trex boards”. Its horizontal-board Horizons gate sits in a visible black powder-coated galvanized steel frame.

We install composite gates across Galveston County:

  • Single walk gates in a composite privacy fence line, for side yards, pool equipment and trash access.
  • Double swing gates for a driveway, trailer or boat, one leaf held by a drop rod.
  • Gates for an existing composite fence, when the brand and color are still made. Bring the product name or a spare board to the estimate.

Material questions (what composite is, how to clean it) live on our composite fence page. Comparing materials? See wood gates, vinyl gates and aluminum gates, or the guide is a composite gate worth it?

Plan view of two composite gate openings. Left: a single gate, 46 and a quarter inch opening between posts, panel 44 and three-eighths inches, which is the opening minus 1 and seven-eighths inches; its swing arc equals the panel width. Right: a double gate, 130 and a half inch opening, two panels of 63 and seven-eighths inches each, which is the opening minus 2 and three-quarter inches divided by two, with a seven-eighths inch gap between panels and a drop rod on the parked leaf; each leaf sweeps about 5 feet 4 inches. Hinge posts carry a steel stiffener; each post sits in a 12 inch hole 30 inches deep. 46¼ IN OPENING 130½ IN OPENING (2 LARGE PANELS) SINGLE, STANDARD PANEL DOUBLE, DROP ROD ON THE PARKED LEAF SINGLE: PANEL 44⅜ IN = OPENING − 1⅞ IN SWING ARC = PANEL WIDTH DOUBLE: EACH PANEL 63⅞ IN = (OPENING − 2¾ IN) ÷ 2, ⅞ IN CENTRE GAP EACH LEAF SWEEPS ABOUT 5 FT 4 IN Stiffener in hinge post 12 in hole, 30 in deep Drop rod
A-1
DrawingSizing the opening: single and double
BasisTrex Seclusions single and double gate guides (©2013); panel widths by arithmetic
ScaleNot to scale
Drawn to rough scale from one manufacturer’s published guide. The panel is made to fit the opening, so the posts have to be set to the right width, plumb and parallel, before anything is ordered.

The standard openings, in inches

Clear opening between post faces for each Trex Seclusions gate configuration. Anything else is a custom size.

Single, standard46.25 inSingle, large65.75 inDouble, 2 small91.5 inDouble, 2 large130.5 inDouble, max listed144 in
Sources: Trex Seclusions single and double gate guides (©2013); Trex gates page (the large single is listed there as 65½ in; doubles “up to 12′”). The arithmetic checks: 2 × 44⅜ + 2¾ = 91½; 2 × 63⅞ + 2¾ = 130½.

Plan a composite gate opening

Enter the clear opening, inside face of post to inside face of post. You’ll get the panel width, swing space, posts and hardware, using the published Trex Seclusions gate guides as the example system, plus the Galveston rules that can change the plan.

44⅜IN PANEL
Panel
Swing space
Posts
Parts
Drop rod
Height rule
Pool gate

Arithmetic from the Trex Seclusions single and double gate guides (©2013) and the current Trex gates page: single opening = panel + 1⅞ in; double opening = both panels + 2¾ in; standard openings 46¼ in and 65¾ in (the product page lists 65½ in) for singles, 91½ in and 130½ in for doubles; doubles listed up to 12 ft clear. Other brands size differently, so the estimate sets the real numbers. Height rules: City of Galveston LDR §2.501. Pool rules: Texas Health & Safety Code §757.004 and the City pool permit (2021 ISPSC). No prices.

What keeps a composite gate from sagging

A gate hangs off one post and leans on its hinges every time it opens. In the Trex guides, four parts share that load:

  • The frame. Welded galvanized steel, not the composite boards, carries the structure.
  • A stiffened hinge post. A steel stiffener slides inside the 5 × 5 in hinge post, and the hinges screw into that steel. If the hinge post isn’t tied to a fence panel, the guide calls for a heavier stiffener or a concrete-filled post.
  • Adjustable hinges. Set about 6 in from the top and bottom, with at least 1 in between panel and post. Loosening the hinge nuts lets the installer raise the latch side or shift the panel. The guide warns that weather and temperature changes can call for periodic adjustment.
  • An anti-sag cable. A steel cable and turnbuckle run from high on the hinge side to low on the latch side, fixed into the steel frame. Trex now lists it with its gates; the 2013 guide describes it as an option for large panels.

The posts are set in concrete 2–3 days before the gate is hung so the concrete can cure. On a coastal lot, also ask what the hinges, latch and screws are made of. Trex notes stainless steel components are available for coastal installations on its Horizons gates.

Elevation of a 6 foot single composite gate between two posts with a 46 and a quarter inch opening. A dashed outline shows the hidden welded 1 and a quarter inch galvanized steel frame. Two hinges sit 6 inches from the top and bottom on the hinge post, which has a steel stiffener inside. A red anti-sag cable with a turnbuckle runs from 5 and a half inches below the top on the hinge side to 2 inches above the bottom on the latch side, 1 and three-quarter inches in from each edge. The latch is about 36 inches up on the latch post. Posts sit in 12 inch holes 30 inches deep and are set 2 to 3 days before the gate is hung. 6 IN 6 IN ≈36 IN 30 IN 46¼ IN OPENING 12 IN HIDDEN WELDED STEEL FRAME, 1¼ IN SQUARE, GALVANIZED: IT CARRIES THE LOAD ANTI-SAG CABLE + TURNBUCKLE: HIGH ON THE HINGE SIDE (5½ IN DOWN) TO LOW ON THE LATCH SIDE (2 IN UP), 1¾ IN FROM EACH EDGE STEEL STIFFENER INSIDE THE HINGE POST; HINGES SCREW INTO IT. 1 IN MIN. GAP BETWEEN PANEL AND HINGE POST POSTS SET 2–3 DAYS BEFORE THE GATE IS HUNG (CONCRETE CURE), IN 12 IN × 30 IN HOLES
A-2
DrawingInside a single composite gate
BasisTrex Seclusions gate guide (©2013), anti-sag cable kit, Trex gates page
ScaleNot to scale
The composite boards are the face; the dashed steel frame, the stiffened hinge post and the cable do the work. Other brands differ in details.
Elevation of a double composite gate in a 130 and a half inch opening, stiffened hinge posts on both sides and a seven-eighths inch gap at the centre. The parked leaf carries a drop rod with brackets 3 and 14 inches up and a hanger 24 inches up, and the latch about 36 inches up. Two details: over a concrete pad, drill a three-quarter inch hole 8 inches deep; over dirt, dig 8 inches wide by 18 inches deep, fill with concrete and set an 8 inch piece of three-quarter inch PVC pipe as a sleeve. 130½ IN DROP ROD: BRACKETS 3 + 14 IN UP, HANGER 24 IN · ⅞ IN CENTRE GAP LATCH ON THE PARKED LEAF, ABOUT 36 IN UP DROP-ROD STOP, TWO CASES Over a concrete pad 8 IN DRILL ¾ IN × 8 IN DEEP Over dirt 8 IN 18 IN CONCRETE + 8 IN ¾ IN PVC SLEEVE
A-3
DrawingDouble gate: centre gap and drop rod
BasisTrex Seclusions double gate guide (©2013)
ScaleNot to scale
The drop rod is what makes a double gate rigid when closed. Over dirt, the guide gives it its own small concrete footing with a PVC sleeve.

Single or double composite gate?

SingleDouble
Standard openings (Trex)46¼ in; 65¾ in (65½ in on the product page)91½ in; 130½ in; up to 12 ft listed
Opening vs panelPanel + 1⅞ inBoth panels + 2¾ in
Hinges2, about 6 in from top and bottom4, two per leaf
Holds closed withLatch on the latch post, about 36 in upLatch on the parked leaf + drop rod
Ground workTwo postsTwo posts + a drop-rod hole or footing
Good forWalkways, side yards, equipmentDriveways, trailers, boats

Trex Seclusions single and double gate guides (©2013); Trex gates page, checked Sept 27, 2026. One manufacturer’s system, shown as an example.

From estimate to a gate that latches

1. Free on-site estimate. We measure the opening and the swing space, check the ground under the gate, and look at what the hinge post will be tied to. We check the rules for your address, including HOA, pool and front-yard limits.

2. Choosing the gate. Single or double, vertical or horizontal boards, height, color, latch and hardware. If it’s joining an existing composite fence, we confirm the brand and color are still available before promising a match.

3. Posts first. Posts are set in concrete to the opening the panel needs, plumb and parallel, and left to cure before the gate is hung, per the manufacturer’s guide.

4. Hang and adjust. Hinges, latch, handles, drop rod and cable go on, then the gate is adjusted until it swings clear and latches cleanly. We walk it with you.

What affects cost and timing: single or double, standard or custom width, height, the product line and color, the number of gates, new or existing posts, concrete or dirt under a drop rod, removal of an old gate, and permit, pool or HOA review. Financing is available through the providers on our financing page, subject to credit approval.

★★★★★
Very professional and friendly. Gotten automatic gates done and they are done to perfection! Thank you
Tannia Cravinas · Google review · a year ago
★★★★★
Great work. Fast service. Very friendly. I recommend using this company to replace your fence.
Roshanta Bell · Google review · a year ago
★★★★★
Absolutely loved my fence once i saw the finished product. No hassle, no rude interactions, and no inconveniences everything was just perfect. One of the best fencing companies in Texas
Elayn Pineda · Google review · 2 years ago

Reviews shown word for word from the Mustang Fencing Services Google Business Profile (Galveston), captured 2026-09-27.

Questions we get about this

What is inside a composite gate?
A steel frame. Composite boards are less stiff than solid wood (USDA Forest Products Laboratory), so manufacturers weld a frame and face it with composite. In the Trex Seclusions gate it is a 1¼ in square galvanized steel frame hidden behind the boards.
How wide should the opening be for a composite gate?
Wide enough for the panel plus the hardware gaps. In the Trex guides a single opening is the panel width plus 1⅞ in (46¼ in for the standard panel), and a double opening is both panels plus 2¾ in (130½ in for two large panels). Other brands differ, so the posts are set to the gate you order.
Why do composite gates sag, and how is it prevented?
The gate hangs off one post, so the post, hinges and frame take all the load. The Trex system uses a steel stiffener inside the hinge post, adjustable hinges and an anti-sag cable with a turnbuckle. Hinges may need periodic adjustment as weather and temperature change.
Can a composite gate match my existing composite fence?
Often, when the same brand and color are still made: manufacturers build gates from the same boards and cap rail as the fence. Bring the product name or a spare board to the estimate so the match can be confirmed before ordering.
How wide can a composite double gate be?
Trex lists double gates up to 12 ft clear. Past that, a slide gate or a heavier steel-framed gate is usually the better tool.
Can a composite gate be a pool gate?
Only with the right hardware. A pool gate must self-close and self-latch. For HOA and apartment pools, Texas Health and Safety Code §757.004 also requires it to open outward and puts the latch at least 60 inches up (or lower on the pool side only, with limits). For home pools the City of Galveston pool permit requires 2021 ISPSC compliance.
Does a composite gate need maintenance?
The boards need cleaning, not staining (see our composite fence page for care). The moving parts need attention too: Trex notes hinges may need periodic adjustment so the latch keeps catching.

Sources

Checked September 27, 2026. Rules change, so confirm with the City before you build.

  1. Trex Seclusions Gate Installation Guide (single, ©2013) — opening = panel + 1⅞ in, 46¼ and 65¾ in openings, steel post stiffener, 30 × 12 in holes, cure time, hinge and latch positions, 1 in clearance, hinge adjustment.
  2. Trex Seclusions Double Gate Installation Guide (©2013) — 91½ and 130½ in openings, + 2¾ in rule, ⅞ in centre gap, drop rod brackets and footing, optional anti-sag cable kit.
  3. Trex Fencing, Gates — 1¼ in galvanized steel internal frame, 6 and 8 ft heights, 46¼ and 65½ in single openings, doubles up to 12 ft, included hardware, stainless components for coastal Horizons installs.
  4. USDA Forest Products Laboratory, Wood Handbook (FPL-GTR-282, 2021) — Ch. 11–12: wood–plastic composites are less stiff than solid wood.
  5. Texas Health and Safety Code, Chapter 757 (Pool Yard Enclosures) — §757.004 gate rules: self-closing and self-latching, outward swing, lockable, 60 in latch height and exceptions.
  6. City of Galveston Land Development Regulations, Sec. 2.501 — residential fence heights: 8 ft; front yard 4 ft solid or 5 ft if 60% transparent.
Free on-site estimate

Planning a composite gate?

We’ll measure the opening and swing space, check the rules for your address, and walk you through single or double, standard or custom. Free on-site estimates across Galveston County.

Page reviewed September 27, 2026 by Mustang Fencing Services, Galveston. Next review due March 2027.

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