Next Day Free Delivery to London and Most of the UK

Next Day Delivery

Next day free and express delivery is available for most products if the order is placed before 2:00 PM.

Clever Shield trade prices with multi-buy discounts available on most products.

Bulk Discount

Trade prices with multi-buy discounts available on most products.

Coating Applicators & Support  Experienced UK coating applicators for liquid coatings and industrial repairs. Qualified technical support Tel: 01268 472358

Phone Orders Welcome

Lines Open: 9am - 5pm, Monday - Friday for orders and technical support T: 01268 472358

NewSeal 420 DeckDrain

Save £124.30 inc.VAT

Size: 46m2
Color: Black
Sale price£621.49 inc.VAT Regular price£745.79 inc.VAT


Unique drainage and water-retention membrane for use where a water reservoir is required for extensive green roofs of sedum, herbaceous plants, mosses or grass above decks and roofs.

Unlike other products of this type, NewSeal 420 DeckDrain has a bonded geotextile that prevents intrusion of the soil into the water holding cups during back-fill and compression. This results in a permanently larger volume reservoir than any other 20mm-deep green roof membrane.

When the water holding cups are full, the large drainage holes within the HDPE core allow water to easily pass through to the drainage layer below to prevent saturation and waterlogging of the green roof above.

Key Benefits
  • Unique bonded geotextile does not sag into the water holding cups as is the case with loose laid geotextiles.
  • Large drainage holes allow a much higher drainage flow through the membrane than comparative products, ensuring that when the water holding cups are full, the water drains quickly so as not to waterlog the soil.
  • Suspended soil particles (fines) are filtered out by the geotextile layer.
  • Large drainage layer created by the 20mm HDPE core.
  • Tough and durable.
  • Quick and easy to install.
Typical Applications

As a water holding and drainage layer above a deck, flat roof or pitched roof where shallow planting is used to create an extensive green roof.

Suitable Substrate

Directly above primary deck or roof waterproofing membrane.

Product Data

Code: M31

Packaging: Roll: 50m x 0.92m

Colour: Black

Area: 46m²

Technical Data
Installed Performance Result
Water-flow at 20 kPa – 1:80 slope – Upper layer 0.07 l/m/s
Water-flow at 100 kPa – 1:80 slope – Upper layer 0.04 l/m/s
Water-flow at 200 kPa – 1:80 slope – Upper layer 0.02 l/m/s
Compressive strength – Temporary loading >240 kPa
Compressive strength – Permanent loading >120 kPa
Water vapour diffusion resistance – Sd value >604m
Water vapour diffusion resistance – µ value >1208000µ
Water vapour diffusion resistance >3020 MNs/g
CBR puncture resistance 2800.00 N
Tensile strength (Machine direction) 19 kN/m2
Tensile strength (Cross direction) 10 kN/m2
Chemical resistance Excellent
Oxidation resistance Excellent

Payment & Security

Payment methods

Apple Pay Google Pay Maestro Mastercard PayPal Shop Pay Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.


Clever Shield Coatings Safe Checkout Guaranteed

You may also be interested in

Trade Customer? 

Get all the benefits of being a trade customer by signing up for an account

  • Monthly Trade Discount Codes
  • Dedicated technical support team
  • Certified hands-on training courses

Recently viewed