How to water-seal edges of an Absco garden shed?

[bennyboy]

Hi, I constructed an Absco 3m x 3m garden shed on an existing concrete slab as a DIY (totally new to DIY, and highly inexperienced). With the build complete (sparing a few minor issues), I am now looking for steps to seal the edges of the shed, so as to prevent any water ingress when it rains. 

Absco recommend the shed be built with the edges on a recessed concrete slab to prevent this, which wasn't an option as i wasn't sure which shed i was getting when the slab was laid years ago. Question is, how do i seal the inner edges of the shed? 

Some pics of the shed and issue attached, looking for inputs from the community. 

Shed on slabFront entryLooking towards the rear of shedRear right corner, exposed side

[EricL]

Hello @bennyboy

Welcome to the Bunnings Workshop community. It's fantastic to have you join us, and thank you for sharing your question about sealing the edges of your Absco shed.

I suggest having a quick look at this discussion - How to seal the bottom of shed walls? by @jjebw. The product my colleague suggested is the Sikaflex 11FC, you can also use Selleys 290ml Grey Storm Waterproof Gutter And Roof Sealant as an alternative. My only recommendation before using the sealants is to give the area a really good clean with a blower so that there will be no dust and debris when applying the sealant.

If you need further assistance, please let us know.

Eric

[CSParnell]

Hi @EricL fantastic advice there, another great method is to sikaflex down aluminium right angle inside this forms an inside wall against water along with the sikaflex.

[EricL]

Hi @CSParnell

That's an excellent recommendation, let me tag @bennyboy to make sure they see your suggestion as well.

Eric

[bennyboy]

Thanks a lot, Eric. I really appreciate the responses provided.

I'm leaning towards using the Selleys sealant, seeing how it can be applied in the wet as well. 

[bennyboy]

Hi mate, thanks for your suggestion. I didn't understand how to go about this though. Please could you elaborate a bit? 

Thanks in advance, and I really appreciate you taking the time to help me with this request. 

[EricL]

Hello @bennyboy

Let me tag @CSParnell to make him aware of your question. Please just keep in mind that not only do you need to seal the bottom edge of the shed, the gaps where the panels sit in the "U" channel need to be sealed both inside and outside to prevent water from coming in. 

If you need further assistance, please let us know.

Eric

[CSParnell]

Hey @bennyboy,

What you are doing is installing a lipped barrier internally to your shed with the use of the ally angle.

I suggest using the sausage polyurethane as its better bang for your buck, you want to apply a seal to the bottom edge if the shed and depending on how much water is actually coming in you might want to seal in the channels as well but this will use a lot more polyurethane. The apply a line of sealant to the top half of the ali right angle and the underside if required if not enough spill over from sealing bottom of shed and stick the ali down so it forms an internal lip.

Why I say if you require to seal in the channels that if you get down pours and water is likely to rise hight than 25mm of the lip of the ali channel? 

So here is the products to use.

 

 

 

[bennyboy]

Thanks a lot @CSParnell and @EricL .

I've gone ahead and bought Sikaflex as per the initial recommendation, along with the caulking gun, and will give your recommendations a try.

I don't believe there is a large ingress of water, so a bit undecided on installing the aluminium angle as an additional barrier yet.. however will update if this is not the case. 

Thanks once again. Shall update once I have results. 

[CSParnell]

No problems @bennyboy see how u go as you said you can always add afterwards if required. Make sure the concrete is nice and clean and free from dust prior.

Let us know how you go.