Frequently asked questions
Does Ultra Drain rust?
No. The alloy grating is anodised to marine-grade specifications.
Which size of Ultra Drain should I use?
It depends on the surface area and the rainfall that needs to be drained from the site. Compare flow rates in our size guide, or call us on 09 415 4588 and we'll help you choose.
Can I drive a vehicle over Ultra Drain?
Yes, with a vehicle up to 1,000 kg per inflated tyre at a maximum speed of 25 km/h, provided the Ultra Drain is encased in concrete as per the installation guide. The channels are not intended for heavy vehicular traffic over 5 tonnes.
Can Ultra Drain be used for a level-entry threshold (E2)?
Yes. Ultra Drain is narrower than the 200 x 150 mm acceptable solution, so it is submitted as an Alternative Solution under E2 External Moisture, backed by fall rates and flow calculations. Auckland Council has approved a UDP 100 substitution through a minor variation. See our E2 guide and download the council pack.
Is the Ultra Drain base chemical-resistant?
Yes, it is resistant to all standard household chemicals.
What is the temperature limit of the Ultra Drain base?
A maximum water temperature of 55 °C.
Is the alloy top chemical-resistant?
The alloy top withstands all pH-neutral cleaning products. Acid or highly alkaline cleaners may damage it.
Does the alloy top get hot?
Aluminium is a good reflector of both light and heat radiation.
How strong is the aluminium?
Aluminium alloys have a tensile strength ranging from 70 to 700 MPa. The alloys most often used in extrusion are 50–300 MPa.
What do I use to join the Ultra Drain parts together?
PVC solvent cement, readily available from any DIY outlet or plumbing supplier.
Can I get customised lengths?
Yes. Customised lengths are available on indent, with a minimum run of 3,000 lineal metres.
Can the packaging be customised for my company?
Yes. A surcharge applies for design and printing, with a minimum run of 2,000 boxes per size.
Is delivery free?
Yes, orders through ultradrain.co.nz are delivered free, New Zealand wide.
Council & compliance
Level-entry thresholds & E2
The NZ Building Code's acceptable solution for a level-entry threshold drain is 150 mm deep and 200 mm wide. Ultra Drain channels are slimmer, but they can still be approved as an Alternative Solution under E2 External Moisture. The Code is performance-based, so council must assess the evidence you provide, not just the dimensions.
What to include with your application
- Fall rates for the surrounding surfaces that discharge to the channel
- Hydraulic calculations showing the drain's flow capacity
- Supporting documents, such as our threshold letter and a precedent council approval
Proven with Auckland Council
On a recent Auckland project, the originally specified threshold drain was replaced with an Ultra Drain UDP 100 through a Minor Variation Application, which council approved. Our download includes that approval (personal details removed) and an installed photo.
Guidance only. Approval sits with your Building Consent Authority; check with your architect, engineer or council early in the process.
Quick flow check
NIWA has recorded up to 123 mm of rain in one hour in NZ, about 2.05 L/min per m². Enter the area that drains to your threshold:
Rated flows from the 2026 Ultra Drain brochure. Use the outlet layout and falls in your calculation.
Size guide
Compare the range
| Spec | UDP 45 Tile Insert | UDP 45 | UDP 75 | UDP 100 | UDP 130 |
|---|---|---|---|---|---|
| Water flow | 150 L/min | 300 L/min | 400 L/min | 570 L/min | 700 L/min |
| Internal width | 101 mm | 101 mm | 75 mm | 120 mm | 130 mm |
| Overall width | 106 mm | 106 mm | 80 mm | 120 mm | 160 mm |
| Height | 45 mm | 45 mm | 105 mm | 102.5 mm | 115 mm |
| Vehicle rating | 1,000 kg per tyre | 1,000 kg per tyre | 1,000 kg per tyre | 1,000 kg per tyre | 1,000 kg per tyre |
| Lengths | 2 m | 2 m | 2 m | 2 m | 2 m |
Vehicle rating applies when the channel is fully encased in concrete as per the installation guide, at a maximum of 25 km/h. Not intended for heavy vehicles over 5 tonnes. All channels come in 2 m lengths. Not sure which size suits your site? Call 09 415 4588.
Trade pricing
Trade pricing available
Builders, landscapers, pool builders and plumbers: enquire direct for trade pricing on the full range.
Free delivery NZ-wide
Talk to a drainage expert
Tell us about your project and we'll help you pick the right channel, outlets and accessories.
- Phone 09 415 4588
- Email hello@ultradrain.co.nz
- Showroom
SSL Distributors showroom, 98 Hillside Road, Wairau Valley, Auckland 0630