Measure the clear width of the opening where the wood gate will sit — not the trim or wall-to-wall nominal width — at both floor level and gate height, then choose a gate whose stated range covers the smallest result.
A gate that arrives in the wrong size means a return label and another week of the dog roaming free. The culprit is almost always a measurement taken outside the trim, or a single measurement taken at floor level only, when the usable passage is what the gate actually has to span. Once the clear opening is right, the rest — height, slat spacing, mounted versus freestanding — falls into place.
Step By Step: How To Measure A Dog Gate Opening
Measure the unobstructed passage in inches at the bottom, middle, and top of the opening. Record the narrowest of the three, because walls, molding, and baseboards are rarely parallel.
- Measure between the mounting surfaces. For a pressure-mounted or hardware-mounted gate, that means the actual face of the wall or jamb the hardware contacts — not the doorframe’s advertised width.
- Measure at floor level and again at your intended gate height. Use the smaller number for sizing. A wall that bows inward at the bottom is the most common source of a gate that “should have fit.”
- Check for obstacles. Baseboards, uneven flooring, stair nosings, and nearby furniture can stop a gate from sitting flush.
- Measure height from floor to the top of the barrier. The American Kennel Club advises that height must prevent jumping — roughly 20 inches may suit small dogs and puppies, while larger breeds or jumpers may need at least 30 inches.
- Confirm the usable span, not the panel length. For a freestanding folding gate, measure the opening and make sure the gate’s supported span covers it after accounting for folded panels.
The finished number is your sizing figure. Write it down and take it with you to the product page; guessing from memory at checkout is how the wrong gate gets ordered.
Sizing Numbers For Actual Wood Gates
Wood gates come in a wider spread of adjustment ranges than metal pressure gates, so the fit depends on picking a model whose stated range brackets your measurement. These are verified specifications for two current TRIXIE wooden models.
| Model And Spec | Stated Range | Recommended Pet Weight |
|---|---|---|
| TRIXIE Wooden Freestanding Pet Gate with Door, item 39369 — width | 39.8–71 in | 6–18 lb |
| TRIXIE 39369 — height and depth | 22.5 in tall by 11 in deep | 6–18 lb |
| TRIXIE 39369 — slat spacing | 1¼ in between slats | 6–18 lb |
| TRIXIE Wooden Freestanding Pet Gate, items 39455 / 39454 — width | 25.6–42.5 in | 6–18 lb |
| TRIXIE 39455 / 39454 — height | 24 in tall | 6–18 lb |
| TRIXIE 39455 / 39454 — slat spacing | 1¼ in between slats | 6–18 lb |
| TRIXIE 39455 / 39454 — frame detail | Metal wire 0.157 in thick, non-slip rubber feet | 6–18 lb |
Two things stand out in that table. The 1¼-inch slat gap runs across every listed model, so slat spacing is a fixed constraint you check once rather than a variable to shop on. And TRIXIE lists the 39369’s height as a step-over design — convenient for people walking through, useless for containing a dog that clears 22 inches without trying.
If you want tested options rather than a spec sheet, our roundup of the best wood dog gates compares the models we’ve actually put in a doorway.
Fit Problems That Show Up After Installation
Most gate failures trace back to one of six measurable mistakes, and each has a fix you can catch before ordering.
- Measuring outside the trim. The trim isn’t structural — the clear passage is. Re-measure between the mounting surfaces.
- Ordering a maximum width equal to your opening. A gate at the top of its range has no slack for mounting hardware or an uneven wall. Buy a range where your measurement lands inside it, not on the edge.
- Treating panel length as supported span. They differ on folding models.
- Buying a 20–24-inch gate for a large or athletic dog. The AKC guidance on jump height applies here.
- Ignoring slat spacing. A small dog’s head or leg can pass through a 1¼-inch gap, and that’s how injuries happen.
- Assuming “listings that mention stairs” means stair-rated. Check the manufacturer’s mounting instructions directly before trusting a gate on a staircase.
Freestanding wood gates deserve their own caution. Non-slip rubber feet reduce sliding, but they don’t replace wall mounting, and a determined or climbing dog can push or knock over a freestanding barrier. The AKC also recommends pet-safe finishes on wooden gates and a gate matched to your dog’s size, activity level, and listed weight limits — a 60-pound dog is outside the 6–18 lb recommendation on both models above, no matter how the gate is measured.
After installation, check the hinges, latch, feet, slats, and wall mounts. Stop using the gate if the wood splits, the hardware loosens, or the gaps change.
The Measurement That Actually Matters
One number decides whether the gate works: the narrowest clear opening width, taken between mounting surfaces, at the height the gate will sit. Use that figure to select a model whose adjustment range brackets it with room to spare, then verify height against your dog’s jump, slat spacing against your dog’s head size, and mounting method against both your wall and your dog’s strength. Write the numbers down before you shop — that alone prevents most of the returns in this category.
Common Questions
Should I measure the doorway or the gate itself?
Measure the opening where the gate will sit — the clear distance between the surfaces the gate contacts. Gate dimensions listed by manufacturers describe the product, not your passage. Use your opening measurement to find a gate whose stated adjustment range comfortably includes it, allowing a small margin for hardware and uneven walls.
What height gate do I need for a dog that jumps?
The American Kennel Club’s guidance is that height must prevent jumping. Roughly 20 inches may work for puppies and small dogs, while larger breeds or dogs that clear low barriers often need at least 30 inches. Watch your dog around a low barrier before committing — a dog that hops 20 inches will treat a step-over gate as a suggestion.
Can I use a freestanding wood gate at the top of stairs?
Only if the manufacturer’s instructions specifically approve stair installation. Freestanding gates rely on weight and non-slip feet, which a dog can push past, and stairs add a fall risk. For any stairway, confirm the approved mounting requirement in the product documentation before use.
Sources
- American Kennel Club. “How to Choose the Best Dog Gate for Your Home” Supports jump-height guidance, pet-safe finishes, and matching gates to a dog’s size and weight.
- TRIXIE. “Wooden Freestanding Pet Gate with Door, adjustable” — item 39369 Source of the 39.8–71 inch range, 22.5-inch height, 1¼-inch slat spacing, and 6–18 lb recommendation.
- TRIXIE. “Wooden Freestanding Pet Gate, adjustable” — items 39455 / 39454 Source of the 25.6–42.5 inch range, 24-inch height, slat spacing, wire thickness, and non-slip feet.