Can you recommend an external waterproof sealant

[DaveB]

Yes I think capillary action is part of the problem, there’s three coats of Sikkens wood preservative on the building and I was very particular on the end grain of the supports

Is the product a water repellent ?

That is what you need if the problem is capillary action, although ideally it would have been applied before the timber is assembled....

 

[Erie Fred]

We used to have home improvement show from Detroit I listened to "Glen Hagey".

Was a good guy, he used to suggest to find leaks employ someone with a Infrared camera,
they can find leaks even after they dry up.

Many times the leak is pretty far away from where you see it, coming in and running along some beam/ceiling/etc.

He had a saying "Water always wins, that's why there is a Grand Canyon".

 

[AVI_8]

Is the product a water repellent ?

That is what you need if the problem is capillary action, although ideally it would have been applied before the timber is assembled....

Yes it is a water repellent but applied after it was built, logistically it would have been very difficult to apply 3 coats prior to building it, there’s a lot of wood

 

[roofman]

We used to have home improvement show from Detroit I listened to "Glen Hagey".

Was a good guy, he used to suggest to find leaks employ someone with a Infrared camera,
they can find leaks even after they dry up.

Many times the leak is pretty far away from where you see it, coming in and running along some beam/ceiling/etc.

He had a saying "Water always wins, that's why there is a Grand Canyon".

Nah..it was the lily livered bedrock that gave up, they just don't make canyons as they used to anymore.

 

[gaz1]

Yes I think capillary action is part of the problem, there’s three coats of Sikkens wood preservative on the building and I was very particular on the end grain of the supports

About 3 inches Gaz

deckings 120x 25 or different thicknesses

its about 9.00 -10.00 a 3m length

check as some decking is twin sided

 

[tom2207]

could you caulk the seam with something ,,, then go down the putty route , or one of the creeping crack cures ,,, trying to remember but Captain someones creeping crack cure springs to mind ,,,


no Im not messing about , its a real thing

 

[tom2207]

https://www.amazon.co.uk/Captain-Tolleys-Creeping-Crack-sealer/dp/B00JQ6XHWC

there you go

 

[tom2207]

could you take the strips off , do the back of them with butyl rubber and then put them back on , so they then have a rubber backing to work as a gasket ,,,,

 

[AVI_8]

I’ll try the sealant, don’t hold much hope for it though as a long term fix, the plan Gaz suggested was something I had thought about and I don’t see why it won’t work as I’ve no problems anywhere other than these 90 degree parts, by covering them over it will stop the driving rain getting to the end grain which is where I think the water is entering at the joins through capillary action all the way down the supports.

 

[Morrisman]

Sikaflex and the like is probably the best stuff for that.
I use it to seal up horseboxes and it seems to last pretty well.

I've got a load of out-of-date tubes of white if you want some cheap to try out?

We used to use Sikaflex for sealing sailing boat woodwork up, thru hill fittings etc, when I worked in a yacht marina years ago. Sticks like s**t to a blanket.

 

[addjunkie]

I’ll try the sealant, don’t hold much hope for it though as a long term fix, the plan Gaz suggested was something I had thought about and I don’t see why it won’t work as I’ve no problems anywhere other than these 90 degree parts, by covering them over it will stop the driving rain getting to the end grain which is where I think the water is entering at the joins through capillary action all the way down the supports.

Could a lead flashing be an option, rather than a wood box!

 

[gaz1]

lead tin or other makes no difference as its down to the users preference

but as the op had bought a wood workshop id have thought he wanted wood to match more than something that will look out of place

the reason why ive suggested the decking is its thick enough to last and also roughly the same material as the building itself

it can be routed out and fitted with a rubber seal at rear of it and drilled and screwed to the building

 

[gaz1]

That’s something I was considering, as @8ob mentioned, this building moves with expansion and contraction over the seasons.
I’ll try the Sikoflex and if that doesn’t work I can make up some wooden structures in a U shape to go round the supports fixed with one attachment and the rest in a slot as that’s necessary with this type of building, I can see by the markings on the storm braces that the height of the building varies by more than an inch from summer to winter believe it or not, if done in wood and stained the same colour it’ll blend in with the building.

silicone cant be used same as sikaflex too much building movement

whichever method is used the building boxing will need expansion joints

i know that the wood will move a little but im unsure if it would match the building enough so id consider slide over pieces for the building to adjust up and down easy enough done with wood though or as a cover over at stretch points

left and right isnt an issue the height is

 

[AVI_8]

silicone cant be used same as sikaflex too much building movement

whichever method is used the building boxing will need expansion joints

i know that the wood will move a little but im unsure if it would match the building enough so id consider slide over pieces for the building to adjust up and down easy enough done with wood though or as a cover over at stretch points

left and right isnt an issue the height is

Hi Gaz, yes I’m aware of that as the rear wall had to have a stud partition wall with 2 layers of fire proof plasterboard to meet building regs. Otherwise I think known as a floating wall all of the fasteners I fitted through the frame which I made vertical slots in, I’ll do the same with this