Help with Roof Flashing between two buildings

[mwerty]

Hi there

This is quite a tricky one to describe so I have drawn a picture:

Untitled

• mwerty
• 21 Apr 2015
• 1

We have just built a timber framed garden office as it were, right next to our garage. The building is currently clad in OSB. Our intention is to clad across the fronts of both buildings in pressure treated shiplap cladding to make them appear nicer from the front.

The issue, is that there is a gap between the two buildings. This gap needs covering to prevent water gaining access to the OSB of the left hand side of the Garden Office. We don't want to clad that left hand side (and in fact now cant as we have built the building as the picture shows.

The garden office is going to have an EPDM rubber roof. The garage has a corrugated roof running back to front. My idea is to cover the gap with OSB and then extend the garage roof, with a new corrugated sheet, to the right all the way to the left of the garden office (picture 2).

My issue is I'm not sure how to create a water tight seal with the new corrugated sheet where it buts up against the wall of the garden office. As picture 3 shows I presumably need some form of wall flashing but I don't know what I can use to join the corrugated metal of the garage roof to the OSB OR shiplap cladding of the garden office wall.

Note the reason why i say OR is because we can either clad the wall and then butt the roof up to it, or butt the roof up to it and then clad down to the flashing.

Has anyone got any ideas as to how we could achieve this?

Note that we have already considered raising the height of the roof of the garage but its a lot of work and additional expense.

Cheers
Matt

 

[Nige F]

Flashband is the answer . and use the primer .

 

[matthewjsummers]

Hi

What would the flashband tape attach to? The corrugated roofing sheet? Or a piece of flashing?

Thanks

 

[theprinceofdarkness]

I would go with your sketch, bridge the gap at the garage roof level, then I would lay your first sheet of corrugated with the edge facing UPWARDS against the OSB of the office. Then use the Flash banding from say3"+ above the corrugated on the OSB side (use the primer) and stick it on the corrugated valley. The lowest level of your cladding should overlap the flash banding. The bottom edge of the cladding will suffer from water drips splashing on the corrugated and so should be removable for maintainance and perhaps be splayed away from the OSB and have a drip edge. Or you could have a wider flashbanding so it raises the botom edge of your cladding, but it should be > 6" to have any effect at all.
Frank

 

[mwerty]

HI Frank

Thanks for your reply. I think I understand, do you mean something like this:

Untitled

• mwerty
• 23 Apr 2015
• 1

I'm not sure I follow what you mean with having wider flashbanding so it raises the bottom edge of the cladding? Can you clarify?

Also, how could I go about splaying the bottom edge of the cladding away from the OSB/giving it a drip edge?

Thanks
Matt