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How to install fascia and soffit on flat roof?

Hi all,

Working on a flat roof extension for a large undercover deck (not enclosed).

What would you call this end beam?
Its a 200x63 LVL tying all of the rafters together.

Secondly, how would you go about installing a metal fascia and ceiling cladding/soffit in this situation?

Standard fascia clips won't work since the rafter ends are not exposed.

So... maybe screw a timber fascia board over the top then proceed as normal, or attach a metal fascia cover and guttering directly onto the beam? What would the soffit/ceiling cladding sit on where it meets the fascia?

Appreciate any ideas/insights.
cheers

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EricL

Hello @Stuckster

The beam at the end that ties all the rafters together is commonly referred to as a "fascia beam," "end beam," or "ledger beam" in this context. Given that it is an LVL (Laminated Veneer Lumber) beam, it is structurally designed to provide support for the rafter ends while also potentially carrying the weight of the guttering system and soffit.

Fascia & Gutter Installation Options

Since the rafter ends are not exposed, standard metal fascia clips won't work. Here are two possible solutions:

Timber Fascia Board Approach (More Traditional)

Screw a timber fascia board onto the face of the LVL beam.
Attach the metal fascia to the timber fascia board using standard fascia brackets.
This provides a more standard setup for installing gutters and also gives a neat finish.
The soffit/ceiling cladding can then be fixed to battens installed underneath the rafters, meeting the back of the fascia board.

Direct Metal Fascia & Guttering (More Modern)

Instead of a timber fascia, you can fix a metal fascia cover (such as COLORBOND fascia covers) directly to the LVL beam using appropriate fasteners.
The gutter can be secured directly to the fascia cover using concealed gutter brackets.
For the soffit, install a timber batten or metal top hat section underneath the rafters, right behind the fascia, to provide a fixing point for the ceiling cladding.

Soffit/Ceiling Cladding Fixing

To support the soffit (e.g., VJ boards, FC sheeting, or aluminium battens), you’ll need support battens running perpendicular to the rafters.
The battens can be timber (e.g., 70x35mm pine) or metal top hats, spaced as needed to support the cladding.
Where the soffit meets the fascia, you can either:

Fix it directly to the back of the fascia board if using timber.

Use a small L-angle or timber trim to create a neat transition.
Key Considerations

Ensure the gutter has the correct fall for drainage.

If using a metal fascia cover, check compatibility with your chosen gutter system.

Plan for ventilation under the roof, depending on local building codes.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let us know.

Eric

Nailbag

Hi @Stuckster

I don't think I can add any more information than the great advice already provided by @EricL, other than your cheapest and easiest facia material will be timber. I love the finish of a metal facia, but it is very difficult to install as it can bend or twist in the process as it can kink fairly easily ruining the finish.

Nailbag

Dave-1

https://www.workshop.bunnings.com.au/discussion/comment/48989#Comment_48989

Morning @Stuckster

I am with the same opinion as @Nailbag , If I had to choose one to recommend I like the idea of the added timber facia board to make it easier overall that @EricL has suggested as the one id choose, but all of them work 🙂

With the timber battens to support the underside of the facia (soffit) I had to look up the meaning of the name 🙂 I also agree with that as the way it should be done.

Dave

Stuckster

Thanks for all the good info chaps.

Outlining those options is really helpful - thanks Eric.

Interesting that you all prefer to go with timber for the fascia boards. I'd really prefer to use a metal fascia cover to make the whole thing maintenance free (if possible).

Rather than buying timber fascia boards to go over the existing fascia beam, I wondered whether the money could be spent on some custom fascia covers to fit over the beam and allow for connection with the soffit, as per below.

This would be easy enough to fabricate, essentially just some Colorbond L flashing with some ridges and a hem on the bottom edge. This would give it some added rigidity. With Nailbag's advice in mind, perhaps two people could lift and clamp it before fixing, to reduce the risk of kinks and bends, or maybe it could be installed in smaller sections. Am I being overly optimistic about the process?

Obviously this drawing doen't have battens for the ceiling cladding, which brings us to the second part.

I assume you're advising to use battens to minimise any variances in the height of the rafters so the ceiling looks nice and flat. But won't the variances in rafter height transfer through to the battens? So presummably they need to be levelled out with packers or furring strips etc. That got me thinking that maybe the bottom side of the rafters could be packed out using a laser level and some timber strips. The cladding could then fix directly to the rafters. Can you see any issues with this?

Failing this the metal fascia cover could be made longer to accomodate the additional height of the battens.

Many thanks.

EricL

https://www.workshop.bunnings.com.au/discussion/comment/49050#Comment_49050

Hello @Stuckster

If you were going to use steel, my best advice is to make sure that the materials are available, and to give yourself enough time if it needs to be specially ordered. I also suggest ordering it in sections as the odds of damaging a long piece of soft steel during delivery and transport is very high.

In regards to the soffit, nailing it directly to rafters is generally not recommended due to structural and performance issues. Rafters are usually spaced too far apart to provide adequate support, which can lead to movement, warping, or sagging over time. Without enough fixing points, the cladding may loosen, causing potential damage and costly repairs.

Battens play a crucial role in ventilation and moisture control. Fixing cladding directly to rafters eliminates the air gap needed to prevent condensation buildup. Trapped moisture can cause timber rot and mould growth in cladding. Battens create airflow, reducing these risks and ensuring long-term durability.

Thermal and acoustic benefits are another advantage of using battens. The air gap helps reduce thermal bridging, improving insulation and energy efficiency. It also dampens noise transmission, enhancing soundproofing. Battens provide a level and adjustable fixing surface, making installation easier and more precise.

Additionally, many building codes and manufacturer guidelines require battens for compliance and warranty validity. Skipping them can result in non-compliance and potential structural failures. While battens add an extra step to installation, they significantly improve the durability, performance, and lifespan of the cladding, making them essential for a well-built structure.

If you need further assistance, please let me know.

Eric

Stuckster

https://www.workshop.bunnings.com.au/discussion/comment/86612#Comment_86612

Thanks Eric.

Forgive me if I'm wrong... but your response reads a lot like AI generated content, which I find can be quite general in nature and lacks the specificity necessary for more complex issues. Either way it raises some points worth considering.

Most rolled Colorbond flashing is widely available and most fabricators only need a few days lead time, so that should be fine.

Regarding the ceiling cladding, our rafters are 450 centres, so no problem with adequate support or sagging.

The roof will have a roof blanket and insulation batts which should control most of the moisture/condensation, so I'm not too concerned about that. Battens would create an air gap under the rafters which is def worth considering, but I guess any moiture would then get trapped between the battens and the cladding. So it's really just transferring the issue.

The ceiling is outside so I don't think we would notice the minor thermal or acoustic benefits.

Last but not least, the building standards (AS2589 2021 Gypsum Linings) seem to allow fixing gyprock directly to the framing, provided that it meets certain tolorances (variations not greater than 4-5mm).

"For wall and ceiling framing that meets the dimensional tolerances of this Clause, gypsum
linings may be fixed directly to the framing with an appropriate fastening system in
accordance with Clause 4.4.3."

This only deals with gypsum, so for other products such as fibre cement sheeting or timber slats we would need to adhere to the manufacturer's specifications. But another good point to keep in mind.

Dave-1

https://www.workshop.bunnings.com.au/discussion/comment/108709#Comment_108709

Afternoon @Stuckster

I would say that nothing that the Bunnings guys post or even the community members is AI generated, the level knowledge the Bunnings Moderators have, has been specific to questions and dosnt have that waffle that AI tends to show. Also if you follow the interactions over dozens of projects you see how much knowledge they have and how it is expressed. Goes for the community members as well btw.

Just have a look through peoples posts and you will soon learn the style that all the members have.

Dave

Nailbag

https://www.workshop.bunnings.com.au/discussion/comment/49050#Comment_49050

Hi @Stuckster

I mentioned timber was the cheapest option, and that my preference was a colourbond finish. It's just from experience it's the more difficult one. If you're going ahead with that design, then have a C-fold so the top of the timber is not only protected, but will make it much easier to install. Give yourself a few mm extra height to allow for imperfections in the timber facia being dead square. You can seal/fill the gap underneath with a matching silicone. Also have wrapped ends, not open ones. Again for a better cosmetic finish.

Other than the centre peak, all other facias seen in this photo are a colourbond wrap.

Nailbag

Stuckster

https://www.workshop.bunnings.com.au/discussion/comment/86630#Comment_86630

Thanks @Nailbag. Looks great. Sounds like what I'm gunning for.

Someone pointed out that traditional metal fascias are designed the way they are to provide a drip edge to stop water wicking along the soffit. Presuming you would need something similar with a custom Colorbond wrap?

Would something like this work? Also is this what you were suggesting with the C fold?

How do your colorbond wraps connect to the soffit?

Nailbag

https://www.workshop.bunnings.com.au/discussion/comment/108743#Comment_108743

I couldn't say for sure @Stuckster as mine wall all custom made by a mate of mine who specialises in custom roofing, flashing and guttering. He had the basic C-sections panels made up, then trimmed and folding them on site.

Nailbag

EricL

https://www.workshop.bunnings.com.au/discussion/comment/121685#Comment_121685

Hi @Stuckster

Here are some links to the Lysaght Novaline Ironstone Fascia brochures. You might find them useful in your research - Lysaght Rainwater Solutions and Novaline Fascia Cover.

Eric

Stuckster

https://www.workshop.bunnings.com.au/discussion/comment/129838#Comment_129838

Many thanks @EricL

Stuckster

Is there a way I can change the title for this post to "Flat Roof - Fascia and soffit installation" (which I think was the original title).

The current title "How to extend a flat roof?" doesn't accurately describe the content and other readers may find it misleading.

Thanks.

Dave-1

https://www.workshop.bunnings.com.au/discussion/comment/50163#Comment_50163

Afternoon @Stuckster

You can edit a question/project for awhile but then it locks in (I have made many many spelling mistakes lol)

Its a Month since you posted so I would say one of the Bunnings crew @EricL , @JacobZ or @MitchellMc will be able to.

Dave

Jason

https://www.workshop.bunnings.com.au/discussion/comment/50163#Comment_50163

No worries @Stuckster. That better? We try to ensure titles do accurately reflect the content so that people with similar problems are more easily able to find the helpful advice shared.

Jason

Stuckster

https://www.workshop.bunnings.com.au/discussion/comment/87185#Comment_87185

Much better. Thanks!

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