Undercloak - 4.5mm x 1.2m x 150mm

This 4.5mm Undercloak Strip is intended for use at suitable pitched-roof verges to support a neat, consistent edge beneath the roof covering or mortar bedding detail. It is a relatively small component, but verge weathering depends on its correct position alongside the tiles, battens and chosen edge-fixing system.

Undercloak strips for properly detailed pitched-roof verges

The stated dimensions are 4.5mm thick x 1.2m long x 150mm wide. The material and exact compatibility must be checked for the roof construction, especially where a particular dry verge or proprietary system has been specified. The strip alone does not create a complete weatherproof verge.

Product options and dimensions

• Undercloak - 4.5mm x 1.2m x 150mm

How to choose the right specification

Measure the verge length and calculate the number of 1.2m pieces including joints and cuts. Check the verge overhang, compatible tiles and whether the roof uses a traditional mortar-bedded or specified dry-fix detail. Do not combine materials from different roof-edge systems without confirming they can be used together.

Installation, planning and maintenance

Fix and support the undercloak in accordance with the roof specification. The finished verge must provide adequate restraint and weathering against wind-driven rain. Work should be carried out with safe roof access, and any change to a verge detail should be checked against the appropriate roofing guidance.

Related materials and helpful advice

Browse roof verge accessories to compare suitable options, and dry verge systems for connected project materials. Check our verge roof tiles when preparing your installation. For further products or buying guidance, see roofing tiles.

Frequently asked questions

What is roof undercloak used for?

It is an element of suitable pitched-roof verge details, helping support a neat roof-edge finish.

What size is this strip?

4.5mm x 1.2m x 150mm.

Is undercloak a dry verge system?

No. A complete dry verge system uses its own specified components and fixings.

How many strips do I need?

Calculate the verge run using 1.2m lengths, including the joint and cutting allowances.

Can I use undercloak under any roof tile?

Compatibility depends on the verge construction and roof-covering specification.

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Roof Tiles & Fittings:

We recommend ordering an additional 10% of roof tiles to allow for any breakages that may occur during delivery or handling. Roof tiles are naturally fragile, and having a few extra on site helps prevent delays and ensures your roofing project can be completed without interruption.

Multiple Products from the Same Supplier

If you're ordering multiple products from the same supplier, your order will be dispatched together once all items are ready. This means the longest lead time will apply.

If you need part of your order sooner, please call us on 01202 113233. We can arrange a split delivery, although an additional shipping charge will apply.