50mm cavity, difficult to maintain damp bridge free?

[epsilonGreedy]

My detached garage is comprised of a single story main block 7.2m x 5.6m plus a store appendage 3.3m x 2.3m externally attached to the shorter 5.6m wall. The store is an architectural feature under a catslide roof.

 

I intend to build the main garage as a double skinned 100mm cavity wall but now I am wondering if I can squeeze a useful extra percentage of internal floor space for the store by dropping down to a 50mm cavity we are talking about an extra 4" or 100mm along the longer 2700mm internal wall.

 

If I, as a beginner brick layer, build this garage above dpc (already doing so below dpc) is there a significant extra risk of wall tie mortar bridges with a 50mm cavity?

[Mr Punter]

No problem at all.  Most garages are just single skin and while they can get a bit damp in extreme conditions they are OK.  If you plan to use the garage as a workshop you may want to insulate the cavity.

[PeterW]

Make it 60mm then get a bit of roofing batten and put a string on either end. Lower it into the cavity and pull it up above  the ties as you go and it will catch the snots. 

[Mr Punter]

57 minutes ago, PeterW said:

Make it 60mm then get a bit of roofing batten and put a string on either end. Lower it into the cavity and pull it up above  the ties as you go and it will catch the snots. 

 

This is something that makes sense but I never see it happen on site.

[nod]

We built both DGs with a 50 mil cavity As mr P said most are single skin 

[Brickie]

As others have said-what is the reason for the cavity?

 

[epsilonGreedy]

On 11/09/2018 at 10:21, Brickie said:

As others have said-what is the reason for the cavity?

 

 

I want to upgrade the approved structure to a nice dry outbuilding as the main house is a bit small with limited loft space for storage plus planning covenants ban a garden shed, so this garage has to be perfect.