Flat roof internal vents = help needed please

[Sunnyside]

Hi
Flat (slightly pitched) felt roof cold space. Built 1967. Felt is in good order. The issue is inside. There are internal vents along the junctions of the walls and ceilings internally.

Sorry the pictures are upside down!




The celing is metal backed board (the architect who is still around tells me it is not AIB). We want to insulate the ceiling with foilbacked insulated plasterboard. This creates ventilation issues.

The roof is a cold space. I cannot understand how the vents work at the ceiling as heat must be ****ing out - which is why we want to seal them. They are also ugly and a dust trap / insect passageway.

The architect tells me the roof space is vented behind the fascias - I cannot see where or how as externally the fascias looks totally sealed to the brickwork!

Do we risk insulating from underneath - hope the existing metal backed board plus the new layer gives a sufficient vapour barrier and the exisitng roof ventilation (wherever that may be) behind the fascias will ventilate the roof space?

 

[freddiemercurystwin]

Your post is very confusing so maybe clarify what the construction is, what it is you are doing, what this architect is doing, is your second pic a ceiling or a wall, pics the right way up please, close up of the flat roof too please. What is AIB?

 

[Alastairreid]

Untitled

• Alastairreid
• 22 Nov 2013
• 1

Untitled

• Alastairreid
• 22 Nov 2013
• 1

AIB asbestos insulated board?

Do you have a continuous ventilation strip along the wall ceiling junction?

I wouldnt imagine this would vent into the attic space, maybe through soffit or over fascia vents.

Never seen that set up before! why dont you ask the architect if your proposal is likely to create problems.

You need to look at what other form of ventilation you have in the house especially if you have gas or fossil fuel fires.

 

[Sunnyside]

Untitled

• Alastairreid
• 22 Nov 2013
• 1

Untitled

• Alastairreid
• 22 Nov 2013
• 1

AIB asbestos insulated board?

Do you have a continuous ventilation strip along the wall ceiling junction?

I wouldnt imagine this would vent into the attic space, maybe through soffit or over fascia vents.

Never seen that set up before! why dont you ask the architect if your proposal is likely to create problems.

You need to look at what other form of ventilation you have in the house especially if you have gas or fossil fuel fires.

Thanks for changing the photos.

AIB - yes Asbestos insulated board.

Yes the ventilation strip runs along the wall ceiling junctions in all the upstairs rooms.
The photos don't show that the ceiling actually slopes with the pitch of the roof. The ceiling is the underside of the flat roof there is no loft space.
I cannot see any fascia vents from the exterior.

The architect advised us to leave as is. He is 88 now though!

It is possible the previous owner (deceased this year so that's how we bought the house) who lived there from 1967 until this year who bought the house off plan from the (now) 88 year old architect has insulated the roof at some stage. Thus the roof may be a 'warm deck' so no external signs of ventilation as it isn't freezing cold which I would have expected. The only way to be sure is to cut an inspection hole but the ceilings being metal sheet backed (and by that I don't mean foil) makes this difficult.

The other totally flat roofs are 'tuff roof' and still under guarantee. These are single storey and internally haven't got the vents along the length of the ceiling / wall junctions like the upstairs rooms. I cannot see any external ventilation on those so presume they are 'warm deck' construction.