How to fix Colorbond roof?

[Tariq]

Hi everyone,

I recently purchased a house and was planning to install solar panels. However, upon closer inspection, I realized my Colorbond roof needs some repairs. There are a few holes, some rust on the bolts, and a larger patched hole that seems like a previous repair attempt.

I've attached some photos of the roof for your reference.

Since I'm unfamiliar with roof repair, I'd appreciate your expertise on the following:

• Overall condition of the roof: Although I haven't experienced any leaks inside the house, I'd like to know the overall state of the roof.
• Remaining lifespan: Considering the current condition, how much longer can I expect the roof to last?
• Repair options: Do I need a complete roof replacement, or could I potentially address the issues with repairs?
• Screw replacement: Would replacing all the screws with a rust converter or sealant be a viable solution?
• Patching large holes: What's the best approach to patching the larger rusted holes?
• Patch durability: How long can I expect a patched repair to last (ideally at least 2-3 years)?
• DIY feasibility: I'm considering tackling the repairs myself. Is this a very challenging task, or can it be done with the right tools?
• Required tools: If DIY is possible, what tools would I need for this project (re-screwing, patching, painting, and applying sealant)?

This is my first time on this forum, and I would truly value your expert opinions on my roof situation.

Thank you for your time and assistance!

Sincerely, 

Tariq

[EricL]

Hello @Tariq 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about Your Colorbond Roof.

It appears that the overall condition of the roof panels are still ok except for the drill points which gave deteriorated badly. Unfortunately, it is difficult to predict how long a patch job would last. Please note that parts of your roof sheet will still be functional and provide coverage, but there is no stopping the advance of the rusted areas. Sanding, cutting and repainting will delay the rust, but it will not stop its advance.

From a repair point of view, I recommend doing a full replacement of the severely damaged panels. This ensures that you won't have to revisit this section of the roofing when the solar panels are attached. You can imagine having to remove the solar panels if the roofing sheets spring a leak.

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

If you have any other questions we can help with, please let us know.

Eric

[Dave-1]

Afternoon @Tariq 

I am wondering how large the rust areas are or if the rust stains make it look like the holes are larger?

The large areas of roofing definently I would replace part of the sheet (the last photo)

The screws that are rusted I would replace but the issue then becomes you are putting screws back into the same hole (needs a slightly larger screw) or a new hole and the old hole rust removed then rust protection and sealed. (make sure they are roofing screws with a rubber backed gromet).

Id actually go for larger screws, once removed the old ones, clean and rust proof the existing hole. Once dry then the larger screws into the panels. For the chunks of clearly rusted sheeting I would be cutting out the rust and slipping a new piece underneath to provide continuation of the roofiing. Make sure you rust proof the edge of the sheets you cut.

This should extend the life of the roof. Tho not sure how long. metals roof do rust with time and then its just a maintenance issue.

Dave

[Tariq]

Hi @Dave-1 @EricL ,

Thanks again for your helpful comments and insights! To move forward with the roof repairs, I'd appreciate some guidance on the materials I'll need:

• Screws: Could you recommend the size of a new, larger screw for replacing the existing ones? If possible, mentioning a product available at Bunnings would be great.
• Rustproofing: What product would you recommend for rustproofing the existing holes before patching?
• Cutting Tool: What type of tool is best for cutting the sheet metal for patching?
• Patch Material: What size and type of sheet metal should I buy for patching the larger hole?
• Edge Rustproofing: Once I cut the patch, how can I best rustproof its edges before attaching it?

I appreciate your continued assistance!

Thanks,
Tariq

[Dave-1]

Afternoon @Tariq 

-I would pull up one screw so you could take it with you to the store. That way you know what is and go for the next size up.

-Dy-Mark 350g MetalPro Rust Converter is what I have used for converting rusted surfaces to something more stable.

-Cutting the tin you could use either Tin snips or a fine cutting blade for a grinder. Id just beware of the sparks from cutting an in place piece of roofing is all.

-I would look around to see if you can find some sheets the same type as what you have before you start tthe process.

-I would use emery paper to remove sharp burrs, wire brush the edge also and then the rust convertor spray paint. 

-For the screw holes before spraying them with the rust converer I would be tempted to sand then back with some emery paper but would check with @EricL first.

Dave

[EricL]

Hello @Tariq 

That's excellent advice coming from @Dave-1. It's exactly what I would suggest, please note that using a grinder will produce sparks so be aware that it is a fire hazard, I don't recommend using it. I suggest using snips instead just to be safe. To attach the same type of roofing material to the damaged area, I suggest using Selleys 290ml Clear Storm Waterproof Gutter And Roof Sealant - Clear.

I recommend removing as much of the rust as possible before spraying it with rust converter. Please keep in mind that once you've used the rust converter not to sand the surface again. Make sure the surface is totally dry before you apply the Selleys Storm sealer. 

Please remember to wear personal protection such as gloves, goggles and a mask when working on your project. 

If you need further assistance, please let us know.

Eric

[Nailbag]

Hi @Tariq both @EricL & @Dave-1 have provided excellent advice. However before going down the path of repair, and for total peace of mind, I would get your quotes on the solar panel system. These guys have the knowledge and work with roofing plumbers to ensure the structural integrity before installations.

Your roof sheets appear to be Zincalume Klip-Lok, which is a cheaper steel product over Colorbond and is typically only clipped down not screwed as well. As @EricL  highlighted, once the system installed the cost to remove and refit the system should any of the sheets continue to rust will extend the period considerably the saving of having solar energy. I have a friend that spend $20K on a system fitted to a roof looking in similar condition. A little over a year later he started to get leaks in a couple of areas and it was recommended that the entire section of roof under his panels and then some be replaced. Other than the cabling the entire system was removed and refitted.

Personally I wouldn't be repairing any of the badly damaged sheets if I was intending to cover them with very expensive solar panels. A potentially small investment to replace a few bad sheets is also something you can do yourself.

Regarding replacing screws with larger ones, they only come in longer lengths not by diameter. You would need longer ones where the current length ones are not pulling in tight. And obviously rubber sealed ones.

Regards, Nailbag

[Tariq]

Hi @Nailbag @EricL @Dave-1 
Thank you very much for your assistance with my roof repair inquiry. Your insights on the different approaches and considerations were truly helpful. I feel much more informed now about how to proceed.

I really appreciate you taking the time to explain things clearly.

Thanks again,

Tariq