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Roof Rib Water Creep Up End Grain - How to seal it?

Afternoon all.

Been renovating a conservatory latter part of the Summer and on the ramp down but missed this problem until now and hoping you can help.

The roof ribs are solid but was originally built without end caps or guttering. Now corrected but the water has been dripping onto the end grain and slowly creeping up the internal timber which is now damp for maybe 100mm … shows that black damp stain that comes with water.

I can cover it to let it dry, no problem. But could use some idea what to seal it with after it dries out which I guess will be some weeks.

Ideas how to seal fully with a solid product would be really welcome as I’m struggling against the weather to finish things off. Cheers

I’ve attached a couple of photos of the external end grain and showing the water problem. And also the internal impact.

Hi Owatrol oil works like wd40 on timber, displacing moisture.

Maybe someone up on the Repair Care systems has other options


Hi Andy, thanks for coming back so quickly.

You mean to apply the Owatrol to draw the water out? Just brush on and leave?

Have to say, have warmed hugely to the Repair Care products, have used Dry Seal and the 2in1 repair products very happily this Summer.

Not seen anything from them that looks like a sealant but certainly worth another look.


Hi Andy beat me to it owatrol is a good option, but can also be used on wood metal to offer protection,i done my workshop in it.The longlivty will depend on many factors,like,the type of wood,how its exposed to the wheither.But as Andy said,it great for displacing moisture.For filling that gap i would use Sikaflex.

Hi Jason, the wood is standard building timber … I think C24 grade and whilst has been up about 30 years is in very good order bar a couple of rotted cill corners due to no guttering being fitted originally.

Does the wood need drying first or will will the Owatrol chase the water out? Currently I’ve covered the ends with several over lapped duck tape to create a run off so it will be slowly drying.

And just looking at the Sikaflex web site there are a good few options. You have a specific one in mind? And again I guess this would be applied after the water properly gone?


Hi Sikaflex 221,i have recommended it before on here.Myself i would let the wood ,dry out as much as you can,then apply owatrol.And yes,apply sikaflex,when its dried out.When i apply deep gaps with sealant,i cross stich and build up in layers.Hope that helps.cheers

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Have to say that sounds like a plan Jason. Yes is exactly what I will do. Super stuff, many thanks

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Looks like the rain is causing you more problems than spotting on new paint! I’m still waiting for a dry day to finish my front door and framework.
Regarding the cladding with Duck tape, I would try a different approach as I think that it would dry quicker than sealing the end grain with the Duck tape. If you could create a hood out of a plastic rectangular container (eg an empty white spirit container) it would keep the water off but allow the air to dry out (albeit slowly) the end grain. You would need do a bit of profiling with a knife to fit between the underside the profiled “ridge tile”, the top of the timber joist and the horizontal facias before finishing say 3 inch below the timber. If you are stumped by my description I could use my Blue Peter skills to knock up a prototype and post it on here.
I hesitate to suggest trying a hair/hot air dryer to someone with your luck with rain but it may be worthwhile?

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I have used it to good effect to prepare raked out long standing rotten sections of window cills. Obviously the longer you can let the exposed timber dry the better. Owatrol hurries along the drying out process nicely. Watching wood dry is way less interesting than watching paint dry!

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Weird that, we had the same conversation here … the duck tape of course purely to create a temporary run off, not a wrap round covering. But my Mother said precisely the same as you, a plastic container moded.

The duck tape is creating like a ski jump off the poly carb to stop what is essentially a sort of crevice or capillary water creep … the water hits the edge (fortunately very small quantities) and then over time seeps back up hill under the poly carb sheet. I think when it was built, the wood should probably have been set back a few millimeters.

Your description is spot on and given it’s a rather sunny of cold Shropshire day then I’m going to have a hack at that. I’ve had a heater and humidifier on inside the conservatory to do what you shouldn’t and rush the Gras de Laquer drying on a bit and that will strangely help the dry to the damp timber from the inside a little. But at the risk of changing the graphics on the BBC weather on-line web site, I’ll also get the hair dryer out as well :slight_smile:

Great suggestions, thanks for that.

:slight_smile: …yeah I guess so and in reality I have time a bit now. The main structure is shaping up nicely … just need one clear weather day put a 2nd coat XD on the one side and then done externally and hopefully internally pretty well done today if can drag myself away from watching CNN!

So will upgrade the duck tape to plastic end cap, encourage some drying with the hair dryer and internal heating and definitely use the Owatrol.

Only trouble there is the can size … I cannot see a small one, seems the smallest starts at £29 odd. If it’s the right thing to do then we will do it anyway but do you know if there’s a small size one of that Andy?


If you sign up to Owatrol’s newsletter you will from time to time get offers like the one that arrived yesterday offering 20% off with the code INT20 - hope I don’t get done for doing this!

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Hi when we used to use a hair dryer, we tapped to a microphone stand,just a thought,or tripod would do.


Nice one, cheers John

Brilliant, cheers Andy …I went for the 500ml although can see now a sample pot could have been gone for.

Suspect I’m going to be using this again so is a good addition to the decorating cupboard :slight_smile:

The temptation to sing along would be painful to the rest of local humanity Jason.

But I have a light on a tripod that would work. Is a good idea for sure.


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We use a moisture meter,you can buy them quiet cheap,i wouldnt paint damp wood,reason being, your trapping it,and will create further problems when the sun comes out.

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Ok yet again so much I didn’t know again that worked like voodoo.

The duck tape did a pretty good job but the fabricated plastic covers fashioned out of Cravendale end of bottle milk bottle was even better. (became a project in it’s own right and a thing of beauty :slight_smile: ).

The Owatrol likewise. I applied it from the inside on the 45 deg and on the end grain on the outside and again … a revelation. And in fact can now see why this stuff potentially so good for oil based paint and indeed I have 4 end of tin XD’s that I’m going to strain and mix and see if it comes up good. Looks promising.

And I did indeed buy a moisture meter which is really good for little money.

I’ve not sealed it up yet. I think I will leave a couple more weeks and indeed can do so without impact now it’s covered well.

Great advice leading to a solid result as always chaps. And more skills learned. Many thanks to you all.

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