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How to replace Polycarbonate Roof?

Hi, need some advise - i have existing laserlite 2000 trimdek profile roof (clear) and i wanted to replace it with laserlite 3000 greca profile (or different brand - greca profile). As the existing would have the screw hole in the metal structure beam, when i replacing it how do i aligned and screw it align to the hold in the metal beam. Any advise? since it is different profile - is it advisable to removed the clear and aligned to the top of the new color roof and do the marking (eventhough both different profile)?

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EricL

Hello @calccom21

Thank you for sharing your question about replacing your polycarbonate roofing. I believe one of the important things to take into consideration is compatibility. The new sheet must fit in with the old one so that there will be no opportunity for rainwater to get through. If the sheets fit together, you can use the same mounting holes that you currently have now. I suggest marking the new sheet with a highlighter and drilling pilot holes for ease of installation. My best advice is to make sure that the new sheet is compatible and that it covers the old space properly.

Let me call on our experienced members @Dave-1, @Nailbag and @AlanM52 for their recommendations.

If you need further assistance, please let us know.

Eric

Dave-1

Good Evening @calccom21

I was wondering why you need to reuse the existing screw points instead of putting new ones in when you change the sheet over.

Then I noticed the top side of the slope of roof, it looks like it still continues upwards. If you are replacing the sheet with a different profile then the transition will be different with the potential for water to make its way in. Same for the bottom overlay, if the shape is too different it wont sit flush nd you will end up with potentall issues as well.

If you are after something that will diffuse the sun more so, why not install that new sheet you are thinking on the underside of the roof, that way you get the sun protection and it stays watertight.

Dave

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/60321#Comment_60321

Hi @Dave-1 can you help me understand what you mean by top side of the slope of the roof and still continue upwards? Also what do you means by installing new sheets underside of the roof? Means 2 layer? Also i was thinking to re use the hole do that I don't have to drill another hole in the metal frame to support the roof

EricL

https://www.workshop.bunnings.com.au/discussion/comment/92630#Comment_92630

Hello @calccom21

"Means 2 layer?"

That is exactly what @Dave-1 is suggesting. Instead of removing your old panel, you can install the new panel at the bottom of the steel frame so there will be a gap. This is on the condition that the new sheet is not a clear one but perhaps a translucent one to prevent full sunlight from coming in. Let me tag @Dave-1 to make them aware of your questions.

Eric

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/112446#Comment_112446

Thanks. Will that need to be same profile? I still can't visualise how I can fit onto bottom.. Means I loosen the bold and add to it? Middle of it there is a beam support. Means I cut the roof to half? What do I need to or use to support the bottom roo any photo?

AlanM52

Hi @calccom21,

Disregard the previously drilled holes, simply lay down the new sheets in the usual way but check that each drill point is flush or not 'too squishy' and if not (maybe profile issue as @Dave-1 mentioned) pad underneath with a window packer.

If needed I trim the packers so they hidden from view.

Cheers

EricL

https://www.workshop.bunnings.com.au/discussion/comment/123746#Comment_123746

Hello @calccom21

The new panel will be attached at the bottom of the steel frame the old and new do not come together. The sheets don't need to come together, and you can leave the top section alone. For a better perspective the old sheet stays on top of the steel frame and the new sheet will be installed at the bottom of the steel frame. It's like a sandwich with steel in the middle.

Eric

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/131211#Comment_131211

Ah.. Thanks it will then looks weird with a hole in between e the 2 frame because the section where the beige colorbond and clear there no metal beam seperating

Nailbag

Mixing any roof sheet profile is always going to be problematic, Sony question back is why you’re replacing the clear sheet as it appears to be in good condition?

Nailbag

EricL

https://www.workshop.bunnings.com.au/discussion/comment/135778#Comment_135778

Hello @calccom21

It is an interesting solution if you don't want to take the old roof sheet apart. But I will leave the choice up to you on how you wish to proceed.

Eric

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/60323#Comment_60323

How do I use packer? Sorry noob here and never heard about packet and where it goes to?

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/60327#Comment_60327

I'm installing solar battery and the clear roof have 100% heat through which is not recommended so I need to put some sort battery friendly for so less heat pass through. I already requested a greca sheet. What is the best way to deal with lol

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/60327#Comment_60327

I would thought it will be easier because trimdek has rib and greca has rib too and so just cut and overlap 1 rib to the other should be fine and the roof is slightly slope downwards

AlanM52

https://www.workshop.bunnings.com.au/discussion/comment/92634#Comment_92634

@calccom21

CC: @EricL, @Nailbag, @Dave-1

I am suggesting we rewind back to the start and clarify a few things.

(Also asking for photos of the patio area and the intended location for the battery)

You are installing a solar battery on your patio and from what you have been researching the 'as new' clear poly should be replaced with tinted poly to provide better battery protection from the sun and if that's the case I have a question.

Are you adding a battery to existing solar panel system or is that battery part of another system.

Cheers

EricL

https://www.workshop.bunnings.com.au/discussion/comment/92635#Comment_92635

Hello @calccom21

Thank you for sharing that extra bit of information. If you still wish to change your polycarbonate roofing, I still recommend making sure that they are the same shape and profile as your old polycarb sheet for easy replacement.

Eric

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/112448#Comment_112448

attached is the photo. Yes it install battery on existing solar panel.it slope from right to left. The panel I wanted to replace will far end near the wall.

calccom21

https://www.workshop.bunnings.com.au/discussion/comment/112449#Comment_112449

Thanks @EricL . So with the same profile it will stick well with the panel next to it. Do I need to put sealant or tape joining the panel or not required since it sits well and had screw on it closer look of the join as attached

Also do you know where I can find these screw with rubber?

Nailbag

https://www.workshop.bunnings.com.au/discussion/comment/92635#Comment_92635

If you’re finding it difficult, you could possibly just fasten the new sheet on top of the old using longer sealed poly screws. The clear sheet still remains as the main waterproofing barrier

Nailbag

Dave-1

https://www.workshop.bunnings.com.au/discussion/comment/112451#Comment_112451

Good Morning @calccom21

The crew have described what I had in mind (will get a chance later to sketch it out if you want) Tho @Nailbag's suggestion of installing a new sheet over the clear sheet would solve the issue nicely.

Some things to note.

When screwing through any roofing sheet, you generally screw through the high points, this is so water dosnt drip through the screw holes in the valleys.

The roofing screws come in a range of sizes depending on what you decide to do - Roofing screws

As the new sheet is unlikely to match up, you could lay three pieces of timber 35mm*70nn H3 timber across where the existing roof suupports for the alsonite are. Remove the existing screws, install the longer ones that @Nailbag has suggested. and then once those three are done you can screw you new "cover" sheet onto the three raised supports.

Dave

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