Part of a build I have been working on this past 12 months.
Rear extension of a bungalow.
Pitched roof
Vaulted ceiling
9x2 rafters
Breathable roof membrane
Steel size is 9m @ 203x203x46kg and is sitting on the inner leaf of the walls.
Windows/doors/bifold were installed just under a week ago to make the area water tight. I have since noticed the RSJ is covered with condensation - especially after this cold snap we have just had.
I am yet to install insulation in the rafters. Will be using rigid board and approx 150mm between (leaving air gap of up to 75mm) and 25-50mm over the rafters and RSJ.
Floor is yet to have screed down and walls are also not yet plastered (built from blocks, thermalite internal and standard dense concrete external with a 100mm insulated cavity)
Question,
Will the 25-50mm insulation over the RSJ prevent condensation build up? Or do I somehow need to insulate the top of the RSJ? Which I am not sure is possible now!
(My architect is not available at the moment so trying to get more info before I am back in touch with him.)
Thanks in advance.
Rear extension of a bungalow.
Pitched roof
Vaulted ceiling
9x2 rafters
Breathable roof membrane
Steel size is 9m @ 203x203x46kg and is sitting on the inner leaf of the walls.
Windows/doors/bifold were installed just under a week ago to make the area water tight. I have since noticed the RSJ is covered with condensation - especially after this cold snap we have just had.
I am yet to install insulation in the rafters. Will be using rigid board and approx 150mm between (leaving air gap of up to 75mm) and 25-50mm over the rafters and RSJ.
Floor is yet to have screed down and walls are also not yet plastered (built from blocks, thermalite internal and standard dense concrete external with a 100mm insulated cavity)
Question,
Will the 25-50mm insulation over the RSJ prevent condensation build up? Or do I somehow need to insulate the top of the RSJ? Which I am not sure is possible now!
(My architect is not available at the moment so trying to get more info before I am back in touch with him.)
Thanks in advance.
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