Garage Door Weather Stripping: Selection, Installation Tips
Weather stripping, also called a garage door seal or astragal, is your first defence against driving rain, salty wind, dust, rodents and energy-sapping draughts. A snug strip along the bottom, sides and top of the door stops moisture pooling on the floor, keeps the temperature steadier and protects that rack of bikes or shelf of paint tins from corrosion and mould.
Replacing or upgrading a tired seal is a quick weekend job needing only basic tools and parts you can pick up at Bunnings, Mitre 10 or order online. This guide walks you through checking whether your door needs attention, choosing the right profile for New Zealand conditions, measuring accurately, installing step-by-step, and keeping everything shipshape for years to come.
Assess Whether Your Garage Door Needs New Weather Stripping
Most bottom, side and top seals soldier on for roughly three to eight years. Beating sun, gritty floors and salty coastal air all hasten cracks or flattening, so north-facing doors in Wellington or Tauranga may wear out sooner than a shaded Invercargill garage.
Telltale signs it’s time to swap the strip include:
- daylight seeping around the panels,
- a shiver of wind or smell of petrol fumes,
- puddles after rain,
- ants or slaters marching inside, and
- rubber that feels brittle, splits when bent, or no longer springs back.
Not sure? Close the door on a strip of A4 paper; if it slides out easily the seal isn’t doing its job. After dark, shine a torch from inside and watch for glowing gaps. Remember, many brand-new roller doors arrive without perimeter or threshold seals, so upgrading can be preventive rather than reparative. In wind-whipped, damp Aotearoa, every garage benefits from effective weather stripping.
Safety and Preparation Checklist
- Disconnect opener and pull the manual release cord.
- Prop the door fully open or lock it with vice-grips on the track.
- Wear gloves and eye protection around sharp aluminium edges.
- Sweep the slab so grit can’t scratch the new rubber.
- Keep kids, pets and curious mates clear of the work zone.
Choose the Right Type of Weather Stripping for Kiwi Conditions
All weather stripping has one job—seal out the elements—but not all strips are born equal. New Zealand’s mix of fierce UV, sea-spray and temperature swings means you need materials that won’t crack by Easter or corrode before next rugby season. Below is a quick cheat-sheet on the main profiles you’ll see on store shelves.
| Type / Material | Best Use Case | Avg. NZ Price / m | Durability ★1-5 | UV Resistance | DIY Difficulty |
|---|---|---|---|---|---|
| EPDM “T” or “Bead” bottom rubber | Roller or sectional door bottoms | $8–$14 | ★★★★☆ | Excellent | Easy |
| Hollow bulb rubber | Uneven or sloping slabs | $10–$16 | ★★★★☆ | Very good | Easy |
| Nylon brush strip | Side jambs on windy, leaf-prone sites | $12–$18 | ★★★☆☆ | Good | Moderate |
| PVC flap perimeter seal | Standard timber/aluminium jambs | $6–$9 | ★★★☆☆ | Fair | Easy |
| Aluminium retainer + vinyl insert | Premium refurb, high sun exposure | $18–$25 | ★★★★★ | Excellent | Moderate |
| PVC threshold ramp | Flood-prone drives, reverse fall | $75–$140 (kit) | ★★★★☆ | Very good | Moderate |
People Also Ask: “What is the best weather stripping for garage doors?”
For most Kiwi homes, EPDM rubber is the front-runner—it laughs off UV and stays flexible in winter. Pair it with an aluminium-and-vinyl jamb kit for a belt-and-braces perimeter. Coastal within 20 km? Use marine-grade aluminium or stainless screws to dodge rust.
Terminology can be confusing: the bottom strip is often called an astragal, bottom seal or door shoe; the side and top pieces are perimeter or jamb seals; combine the lot and you’ve got full garage door weather stripping.
Thinking greener? EPDM contains some recycled content, and old rubber can be dropped at selected Mitre 10 or Bunnings recycle stations. Slice it up first so it packs flat in the bin.
Bottom Seal Styles Explained
Most doors use either a twin-slot “T” track or circular “bead” track. If the old strip has a mushroom-shaped stem it’s a T-style; round ropey stems signal a bead fitting. Measure the track width and match the seal—3″ for smooth concrete, 4–6″ for wavy or cracked slabs needing extra reach.
Side & Top Perimeter Seals
A PVC flap is the go-to on straight jambs, but switch to a nylon brush where leaves or birds are a menace—bristles flex without jamming. Aluminium carriers with replaceable vinyl inserts give a crisp look and can be powder-coated to any Colorsteel shade.
Optional Threshold Seals
If storm water or sand blows under the door, glue a ribbed PVC threshold to the slab. Use a polyurethane adhesive rated –5 °C to 70 °C so it survives Canterbury frosts and Northland summers alike. Let it cure 24 hours before driving over.
Measure, Source, and Budget Your Materials
Accurate measurements save return trips and re-cuts. Work in millimetres and jot figures down immediately.
- Bottom seal length =
door opening width + 100 mm. - Side seals (each) =
jamb height + 50 mmso you can trim flush later. - Top seal = exact lintel width.
- Track check: measure the width of the twin slots for T-style (commonly 6 mm or 8 mm) or the bead diameter (usually 6 mm round).
While you’re under the door, confirm the retainer profile; a quick phone pic helps when ordering.
Typical Kiwi DIY costs
- Bottom EPDM seal: $8–$14 / m
- Perimeter kits (sides + top): $45–$90
- Threshold kit: $75–$140
- Stainless screws, silicone and cleaning supplies: allow $25
Example single-door budget (2400 mm wide, 2100 mm high):
| Item | Qty | Unit $ | Sub-Total |
|---|---|---|---|
| Bottom seal 2.5 m | 1 | 12 | $30 |
| PVC perimeter kit | 1 | 60 | $60 |
| Consumables | — | 25 | $25 |
| Estimated spend | $115 |
Buy local if you need help matching profiles, or order online to get 5 m or 10 m rolls shipped free to most North Island addresses—handy when you’re refitting a multi-bay workshop.
Tool List You’ll Need
- Tape measure & pencil
- Utility knife with fresh blades
- Rubber mallet
- Phillips driver or drill with 8 g bit
- Hacksaw or tin snips (for aluminium carrier)
- Dishwashing detergent (lubricant)
- Isopropyl alcohol wipes for bond prep
With materials and tools sorted, you’re ready to prep the door for new garage door weather stripping.
Prepare the Door and Work Area for Installation
A tidy, stable workspace saves skinned knuckles and crooked seals. Start by raising the door to head height and pulling the manual release so it can’t jump when you’re underneath. Unplug the opener and clip vice-grips on the tracks just above the rollers to lock the panel in place. With safety sorted, strip off the old weather seal: back out any retainer screws, then slide the rubber clear and bin it for recycling.
Next, give the aluminium tracks and panel edges a thorough wash with warm, sudsy water, rinse, and dry with a rag. Follow up with a quick wipe of methylated spirits or isopropyl alcohol to banish grease that would stop new adhesive or rubber from bedding in. Finally, inspect the jambs for soft timber or oxidised metal—patch or prime now, because a fresh seal won’t fix structural woes.
Fixing Irregular Floor Gaps Before Sealing
Uneven slabs bigger than 5 mm invite leaks. For shallow dips, pour a self-levelling compound and let it cure overnight. If the concrete peaks rather than sags, shim the aluminium retainer with thin plywood or PVC packers so the new bulb compresses evenly. Severely bowed door panels may need a professional tweak before you proceed.
Install the Bottom Seal: Step-by-Step Walk-Through
With the door cleaned and locked off, you’re ready to slide in the new strip. Aim to work in the shade so the rubber stays pliable and the dish-soap lubricant doesn’t flash dry.
- Mix a squirt of dishwashing liquid with a cup of water. Paint the solution along both channels of the aluminium retainer; this slicks the way for the new seal.
- Fold the first 100 mm of seal double to create a “lead-in” and insert both beads (or T-tails) into the tracks. A helper is handy on doors wider than 3 m.
- Feed the seal steadily, pushing rather than pulling to avoid stretching the rubber. If it binds, tap the retainer gently with a rubber mallet while your mate advances the strip.
- Once the seal protrudes equally at each end, drop the door and eyeball the compression. If a gap shows, open the door and tug the seal down in that area, then re-test.
- Trim excess with a sharp utility knife, leaving a 20 mm overhang so future tweaks are possible.
- Stop the seal drifting later by crimping the retainer lips with pliers or driving a stainless 10 g screw through each end bead.
Job done—fresh garage door weather stripping now hugs the slab and blocks out the southerly.
Installing PVC or Brush Side & Top Seals
A consistent line is the secret to an even seal:
- Close the door and mark a pencil line 5 mm off the panel face down each jamb; this is your screw line.
- Pre-drill 4 mm holes at 400 mm centres, then fasten the strip starting at the top hinge and working down.
- Fit the top seal last, overlapping the side strips by 20 mm so rain sheds cleanly.
- Snip any brush longer than the gap; bristles should just kiss the steel, not buckle.
Bonding a Threshold Seal (If Needed)
- Dry-fit the PVC ramp, then mark its outline with painter’s tape.
- Wipe the concrete with isopropyl alcohol and let it flash off.
- Gun a continuous 8 mm bead of polyurethane adhesive inside the tape lines and press the threshold into place.
- Close the door until the rubber astragal nests in the groove, weighting the seal while it cures (about 24 h).
- Remove tape, trim any squeeze-out, and keep vehicles off for a full day.
Your garage is now armoured against wind, water and wandering critters.
Maintain, Troubleshoot, and Extend Seal Life
A new seal will shrug off the elements for years, but a little TLC keeps it springy and tight. Work these quick tasks into your quarterly shed tidy-up:
- Wipe rubber or vinyl with warm soapy water; rinse and dry.
- Spray a UV protectant (silicone-free) every six months on north-facing doors.
- Check and re-tighten perimeter screws each Labour Day; timber moves.
Common niggles and fixes:
| Issue | Likely cause | Fast remedy |
|---|---|---|
| Seal keeps sliding | End beads not locked | Crimp track or add stainless screw through bead |
| Light still visible | Seal compressed unevenly | Tug rubber down at bright spot; add shim if slab dips |
| Mice sneaking in | Gap at panel joints | Clip-on brush strip along top panel hinges |
If critters persist, combine a brush seal with peppermint oil sachets for a double whammy.
When to Call a Professional
- Door out of square or sagging more than 10 mm.
- Rusted bottom retainer needing panel removal.
- Heavy commercial roller doors where spring tension must be reset safely.
Quick-Fire Answers to Common NZ Questions
- Can the weather stripping on a garage door be replaced? Yes. Remove the old strip, slide or screw the new one into the existing track, trim the ends and you’re done. Most DIYers manage it in an afternoon.
- What are typical garage door weather stripping prices in NZ? Bottom EPDM seal $8–$14 per metre, perimeter kits $45–$90, threshold ramps $75–$140.
- Where can I buy garage door side seal in Auckland or Christchurch? Big-box chains like Bunnings and Mitre 10 stock common sizes; online suppliers deliver statewide or offer Christchurch depot pick-up.
- How long should a seal last in NZ’s climate? Roughly five years for rubber/vinyl, up to ten years for aluminium carriers with replaceable vinyl inserts.
- Is a brush seal bird-proof? Largely, yes. Dense nylon bristles stop sparrows and starlings without jamming the door.
Wrapping Up
A tight, tidy line of garage door weather stripping is a small upgrade that pays back every rainy, windy day. The recipe is simple:
- Inspect the door and note any gaps or cracking rubber.
- Pick the right profile and material for your site.
- Measure twice in millimetres and buy a little extra length.
- Clean every surface like you’re painting, then install at a relaxed pace.
- Give the new seal a quick wash and UV spritz now and again.
Follow those steps and your garage stays drier, warmer and pest-free while the power bill stays down. Ready for supplies or a full replacement door? Check out the Kiwi-made options at DoorsNZ and keep the weather where it belongs—outside.