How to replace sarking and flashings on tiled roof?

[emmab1986]

Hi,

We have engaged a roofer to replace the sarking and flashings on our tiled roof.

Could you please advise which type of flashing material is considered best practice for this application, and why? We would like to ensure the materials used have a relatively long lifespan and are compliant with relevant standards.

Thank you for your guidance.

[JacobZ]

Hi @emmab1986,

Unfortunately, there is no single flashing or sarking product that is considered best practice in all situations. The most appropriate materials depend on a range of factors, including roof design, pitch, location, climate, proximity to the coast, and how the roof is constructed.

In terms of flashing, commonly used materials include lead, aluminium, and pre-finished steel products. Each option has advantages and limitations based on the specific scenario in which it is used.

For sarking, pliable roof underlays that comply with AS NZS 4200.1 are typically used under tiled roofs. The appropriate class and type of sarking depend on factors such as exposure, roof pitch, and whether additional thermal or condensation control is required.

Rather than there being a single correct product, best practice is that both the flashing and sarking materials are suitable for the specific application, compliant with relevant Australian Standards, compatible with adjacent materials, and installed in accordance with the manufacturer’s instructions.

A good approach is to ask your roofer which flashing and sarking products they intend to use and how they will be detailed, then review the manufacturer's information yourself. This helps ensure the materials selected are appropriate for your home and that the work is being carried out correctly. 

If they are a reputable roofer and you frame your questioning around understanding, rather than suspecting them of trying to get one over you, then I imagine they would be happy to answer any of your questions. If not, then it is likely best to contact other tradespeople for quotes.

Allow me to tag our knowledgeable members @Dave-1, @Nailbag and @R4addZ to see if they have any thoughts they can add.

Jacob

[Nailbag]

Hi @emmab1986 

I think @JacobZ has already explained all I possibly could, in particular his last paragraph which is an excellent approach. 

You could initiate the conversation around any other more effective insulation products available while the opportunity is there?

Nailbag

[Dave-1]

Good Evening @emmab1986 

@JacobZ has described it well One further thing I would add is you can check and verify their licence and see if they have any complaints against their name. 

The department of fair trading in NSW I know list them, Other states will have something similar I am sure. New Zealand will also have something that will show if they are licenced.

Having the questions you have already tends me to think you may not be sure of the builder/contracter. I would hit pause on it until you sort out any issues. @Nailbag 's suggestion on how to start the convo is a good idea.

Dave

[R4addZ]

Ht @emmab1986 

It may help us to know why you have decided this work needs to be carried out.

[emmab1986]

The sarking beneath the tiles was damaged, and the roof was leaking. We decided to fix the leak, so we asked a tiler to come to our house to inspect it.

[emmab1986]

It is an alfresco area of approximately 25 m². When the tiles were lifted, damaged sarking was visible. 

I have another question: the flashing in the attached photo, is it a pressure flashing or what kind of flashing is it?

[EricL]

Hello @emmab1986 

It looks similar to the CAgroup 350mm x 5m Terracotta Ubiflex Finio Flashing. It is a flashing product that is made of aluminium and reinforced isobutanol. It makes it very flexible and easily conforms to the roof material its placed on.

Eric