Basic silly question

[Nic]

This is probably a very silly basic question…. 
in a roof make up as shown is the ducting for the mvhr in the roof as drawn with my red circle and the insulation around it? As the service void for lights is shallow or do I need a bigger service void ? Which would make the roof depth much bigger… I’m sure this is extremely silly and there is an obvious correct way 

🤷🏻‍♂️

[JohnMo]

You haven't said how big you service void is? you need about 50mm to get lights in, but if you just want cables you only need about 25mm

[Nic]

2 minutes ago, JohnMo said:

You haven't said how big you service void is? you need about 50mm to get lights in, but if you just want cables you only need about 25mm

Sorry . yes the plan as set up is about 50mm. The current roof profile is about 300mm deep finish to finish 

[Nic]

Sorry again the picture is not our roof but is just to demonstrate where the builder said the ductwork would have to go 

[Russell griffiths]

Have seen this done exactly how you have drawn it. 
you will need to ensure that plenums for the mvhr are scrupulously sealed around, and also where the ducts drop into the plant room area. 

[Nic]

32 minutes ago, Russell griffiths said:

Have seen this done exactly how you have drawn it. 
you will need to ensure that plenums for the mvhr are scrupulously sealed around, and also where the ducts drop into the plant room area. 

Yes I wondered about that .. thanks