Alpha Air Ventilation Supplies
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Master Flash Closed-Top Roof Flashing 0mm-724mm

Closed-top version of the Maxi EPDM cone flashing: the dome is supplied sealed, so it weatherproofs the opening as supplied and is cut on site to any pipe size up to 724mm when needed.

£288.12

20% VAT added at checkout

In Stock – Available for next day delivery

Order before 3pm today for delivery by Monday 14th September

Choose Your Flashing

SKU: MF-EPDM-MAXI-CT
Category:

Description

The Closed-Top Maxi is the sealed-dome version of the largest standard Master Flash. Supplied uncut, it fully weatherproofs a roof opening as installed — then, when the penetration is made, the dome is simply cut to the exact pipe size, anywhere up to 724mm diameter.

The Master Flash Standard is a flexible cone roof flashing that seals ducts, pipes, flues and vents where they pass through the roof. The square base carries an embedded aluminium band that moulds down onto profiled metal, tile and membrane roofs by hand, forming a lasting watertight seal without specialist tools, and the cone trims to the pipe size against clearly marked steps.

Made from premium EPDM rubber, it resists UV, ozone and weathering, staying flexible from -55°C up to +100°C continuous (+135°C intermittent) — ideal for ventilation ducting, soil stacks and extract terminals.

Frequently Asked Questions

What is a Master Flash roof flashing?

A Master Flash is a flexible cone-shaped flashing that weatherproofs the point where a duct, pipe or flue passes through a roof. The standard version is made from EPDM rubber, which resists UV, weathering and temperature extremes, and the flexible base dresses down onto profiled metal, tile and other roof coverings to form a watertight seal around the penetration.

What size Master Flash do I need for my pipe or duct?

Each Master Flash covers a range of pipe diameters — for example 101mm to 209mm — and the cone is trimmed on site to suit the exact pipe. Across the range we cover diameters from 6mm right up to 724mm. Choose the flashing whose range brackets your duct’s outside diameter, ideally so the pipe lands towards the middle of the range for the best seal.

Do you have a Master Flash suitable for hot flues and high-temperature pipes?

Yes. Alongside the standard EPDM range we stock the Master Flash High Temperature version in the same size options, from 6mm–70mm up to 304mm–724mm. These are designed for hotter applications such as flue pipes and high-temperature extract ducts where a standard flashing would not be suitable. If you are unsure which version your application needs, call us on 0116 246 0031.

How do I install a Master Flash roof flashing?

Trim the cone to a diameter slightly smaller than your pipe, slide the flashing down over the pipe, then press the flexible base to follow the roof profile. Apply a suitable sealant between the base and the roof and fix around the edge at regular intervals. No hot works are needed, and the fitting is straightforward with hand tools from the roof side.

Are Master Flash roof flashings held in stock?

Yes — Master Flash roof flashings are stocked items, and the lead time is shown on each product page. Standard and high-temperature versions are both available across ten size options. Delivery is free on orders over £400 excluding VAT, so flashings ordered alongside spiral ducting and terminations such as weather hats or jet cowls usually qualify.

Delivery Information

In Stock

Next Day Delivery — order before 3pm Monday to Friday for dispatch the same day.

Delivery Options

ServiceEstimated DeliveryCost
Standard Delivery (UK mainland)Next working day from dispatch£15.95 +VAT (£7.95 for small items)
Free DeliveryNext working day from dispatchFree on orders over £400 ex VAT
Click & CollectCollect from our Leicester branchFree
Scottish Highlands & Islands2-3 working days from dispatch£36.95 +VAT

Delivery Area

We deliver to all UK mainland addresses. Scottish Highlands and Islands deliveries may take a little longer. We are not currently delivering to Northern Ireland — Click & Collect remains available.

Questions about delivery? Call us on 0116 246 0031 or email sales@alphaair.co.uk

Returns Policy

Six-Week Returns — No Restocking Fees

We want you to buy with confidence. You can return any standard stocked item within six weeks (42 days) of delivery for a full refund — 100% of the item price, no restocking or handling fees. Trade and business customers get exactly the same rights as retail customers. See our Returns Policy for full details.

Return Conditions

  • Items must be unused and in original packaging
  • Custom-made, bespoke or powder-coated items are made to your specification and cannot be returned unless faulty
  • Items must be returned with proof of purchase
  • Return shipping costs are the responsibility of the customer unless the item is faulty

How to Return

  1. Contact our customer service team to arrange a return
  2. Pack the item securely in its original packaging
  3. Include your order number and reason for return
  4. Ship the item to our returns address

Faulty Items

If you receive a faulty or damaged item, please let us know as soon as possible — ideally within 48 hours of delivery, so we can claim against the courier on your behalf. We will arrange a free collection and send a replacement or issue a full refund. This does not affect your statutory rights.

Questions? Contact us at sales@alphaair.co.uk

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