Macflash Universal Roof Flashing

The Macflash Universal Roof Flashing (RS1) weatherproofs the spot where a vertical pipe or boiler flue comes through a roof. It has an aluminium base with a synthetic rubber collar that grips a 4″ pipe.

What it is used for

Vertical flues from condensing boilers are the main use. It goes on flat roofs and on pitched roofs up to 45 degrees. Because the base can be dressed to the roof, it replaces a lead slate on most jobs, which is cheaper and less hassle to fit. The base has corrugations that can be shaped down over tiles or slates to form a seal.

Macflash flashing at a glance

• Pipe: 4″
• Base: aluminium, with a rubber collar
• Roof pitch: flat up to 45 degrees

Specification

• Range: Macflash
• Maker code: RS1
• Material: Aluminium base with a synthetic rubber collar
• Sizes: 4″ pipe
• Suitable for: Vertical boiler flues on flat roofs and pitched roofs up to 45 degrees

Common Questions

Is Macflash a good alternative to a lead slate?

For a 4″ vertical flue, yes. The aluminium base dresses down over tiles and slates much like lead, and it is lighter and easier to handle on the roof.

Can the rubber collar be cut to fit a different pipe?

The RS1 collar is made to grip a 4″ pipe. A pipe of a different size needs a flashing made for it, so check the flue diameter first.

Does the flashing go on before or after the flue terminal?

Before. Slide it down the pipe, dress the base to the roof, then fit the terminal as the boiler maker’s flue instructions set out.

Fitting tips for Glasgow roofs

Slide the flashing over the pipe before the terminal goes on, with the upper edge of the base tucked under the course of tiles or slates above and the lower edge lying over the course below, so water runs off rather than in. Dress the corrugations down with a soft mallet or by hand to follow the profile. Make sure the collar sits snug on the pipe all the way round. On a boiler flue, follow the boiler maker’s flue instructions, and leave gas flue work to a Gas Safe engineer.

The Macflash Universal Roof Flashing is listed in our boiler flues and flue accessories.

Order online, or collect a flashing from Plumb Parts at 555 South Street, Glasgow G14 0QX. The counter opens Mon-Fri 8am-5pm, and Sat-Sun 8am-1pm.