Garden shed leaking HELP!

ThisIsWeird

For the roof, you need to have it recovered - eg with EPDM as said before.

For the shed wall, I can only assume that certain timber 'tongues' are broken, so allowing water through. Ideally, you'd want to trace where - exactly - it's getting through, and then sort that exact part; it might be a small area.

Is appearance important on that side?! Because, if there are a few gaps between the boards where water is getting through, I can only see that a thick gloop will sort it, and for that you are probably looking at roofing coatings such as Cromapol (lots of different makes). Don't expect it to look pretty, tho'.

So, I'd first look at recovering the roof - that def needs sorting. Then try and pin-point where water is getting through the wall. Perhaps run a spray down the outside, and keep checking if it's coming in.

I think Cromapol make a clear version, which also doesn't have fibres in it. This might be a good solution, provided there aren't large gaps required to be filled. In essence, force it right in between each board joint with a stiff brush. And ditto the shed corners.

I'd leave it all until it dries, tho'.

Try and keep the shed door open as much as possible, to allow the inside to ventilate as much as poss.

SUPERGIRL2020

ThisIsWeird said:

Try and keep the shed door open as much as possible, to allow the inside to ventilate as much as poss.

I have been doing that now the weather is getting a bit better 

Nebbit

I don't think you actually have rot. I could send a picture of real rot at the back of my shed - a hole you can put your hand through. Like yours, it is right up against a fence. However I am responsible for the fence. When I needed to renew some fence panels I was able to make a rough and ready repair to the shed - wet rot wood hardener, screwing a replacement piece of wood in place, and then painting it all with Cuprinol. 

SUPERGIRL2020

Nebbit said:

I don't think you actually have rot. I could send a picture of real rot at the back of my shed - a hole you can put your hand through. Like yours, it is right up against a fence. However I am responsible for the fence. When I needed to renew some fence panels I was able to make a rough and ready repair to the shed - wet rot wood hardener, screwing a replacement piece of wood in place, and then painting it all with Cuprinol. 

A local handyman has replaced the shed roof felt, he said cos the shed is so old (10 years) that if the leak still happens then I need a new shed! 

I'm gonna paint it with a tin of cuprinol ducksback! I previously painted it with cuprinol garden shades which obviously didn't work protecting it in bad weather

ThisIsWeird

SUPERGIRL2020 said:

A local handyman has replaced the shed roof felt, he said cos the shed is so old (10 years) that if the leak still happens then I need a new shed!

I'm gonna paint it with a tin of cuprinol ducksback! I previously painted it with cuprinol garden shades which obviously didn't work protecting it in bad weather

So, the roof has actually been totally recovered in felt? It's been renewed? In which case, the roof, at least, should be watertight. Is it? Are the roof timbers dry?

That leaves the leaks through the wall. Almost certainly this will be coming through either where boards join - they'll have overlaps or tongues, but which are clearly ineffective - or through at the corner where the board ends join to the uprights.

I cannot see 'ducksback' sorting either. That stuff - although decent - is designed for rough sawn timber, and waterproofs flat surfaces. Your issue is not with the 'flat' boards, but likely the joints in between them.

Also, since your shed already has a coating on it, I don't see Ducksback adhering very well to it.

You need a coating that gets into cracks and joints, seals them, and is flexible. 

I mentioned Cromapol before, and your previous handyperson did coat your shed roof in something similar. That same stuff would look pretty awful on your shed side, but probably would do the trick. Perhaps Cromapol's non-fibrous version - 'opaque' - would look fine? I don't know.

https://www.ebay.co.uk/itm/145298204076?

Q: Has you shed now got a completely new felt covering? If so, if the underside of the roof dry?

SUPERGIRL2020

ThisIsWeird said:

Q: Has you shed now got a completely new felt covering? If so, if the underside of the roof dry?

Yes the roof is no longer leaking but the side is still

ThisIsWeird

Cool.

So now you need a proper sealing product. Not 'paint'.

SUPERGIRL2020

ThisIsWeird said:

Cool.

So now you need a proper sealing product. Not 'paint'.

Like the one you suggested?

Cromapol

ThisIsWeird

SUPERGIRL2020 said:

ThisIsWeird said:

Cool.

So now you need a proper sealing product. Not 'paint'.

Like the one you suggested?

Cromapol

I haven't used the non-fibre content type, only the 'full-fat' roofing product, which is very good.

Although I'd be pretty confident that the 'fibre' version would seal your timber shed wall, I think it could look pretty messy. So I'd personally be tempted to use the non-fibre version, assuming it'll look acceptable.

I'd force it right into every plank joint using a stiff brush, then whatever brush over it to finish off and give the smoothest finish. 

So, this is just guesswork, as I haven't used it. What I will suggest, tho', is, 'paint' and 'fence' and stain-type coatings are unlikely to seal the gaps where the leaks are - they are just too thin, and will crack in the joints at the fist signs of movement.

I think you really need to work out where the water is coming in, tho'. That means waiting for a dry spell, making sure the inside wall is also dry, and then raining down on it using a hose pipe. Try vertical rain first, then progressively move the angle so it becomes more like driven rain - keep checking inside for the first signs of ingress. Note each point of entry, and keep going until you are literally spraying sideways! ID all the weak points.

If it turns out the ingress points are quite limited, then there may be a simpler and less messy solution.

smyluk

Are there any gaps between the roof and wall panels? You could look at inserting a foam strip into the gap to take up some of the space and hopefully fill any areas where water could enter.

I've previously used the a sponge rubber seal from these guys for a similar application.