We have a chalet style 1950s Scottish house with the second floor rooms contained within the roof space (not a loft conversion). There is a loft space above the rooms but also small loft spaces in the eaves on either side of the upstairs rooms accessed through small doors in the bedroom walls.

We want to insulate these spaces but are not sure what type of ventillation to install in them to prevent damp. The roof is constructed of wooden boards overlaid by felt then tiles. Each eaves space is only on one side of the house and not connected with loft space above to allow circulation of air. If we install tile vents, we presume there will not be the means for the air to circulate in these areas?

A further factor is that the soffits are made of concrete and therefore it is not possible to vent through these.

Any suggestions?

On 01/11/12 21:58, fresia wrote:
We have a chalet style 1950s Scottish house with the second floor rooms contained within the roof space (not a loft conversion). There is a loft space above the rooms but also small loft spaces in the eaves on either side of the upstairs rooms accessed through small doors in the bedroom walls.

We want to insulate these spaces but are not sure what type of ventillation to install in them to prevent damp. The roof is constructed of wooden boards overlaid by felt then tiles. Each eaves space is only on one side of the house and not connected with loft space above to allow circulation of air. If we install tile vents, we presume there will not be the means for the air to circulate in these areas?

A further factor is that the soffits are made of concrete and therefore it is not possible to vent through these.

Any suggestions?


My loft spaces are cold in winter
because the insulation layer is below them.
It's up to you where the insulation envelope is,
but you do need ventilation in that roof.

Ibought this book,
its cheaper than a sheet of kingspan,
and canadian where they have great temperature differences inside and
outdoors.

http://www.amazon.co.uk/Insulate-Wea...1816849&sr=8-1

fresia wrote:
We have a chalet style 1950s Scottish house with the second floor rooms contained within the roof space (not a loft conversion).
There is a loft space above the rooms but also small loft spaces in the
eaves on either side of the upstairs rooms accessed
through small doors in the bedroom walls.
We want to insulate these spaces but are not sure what type of ventillation to install in them to prevent damp.
The roof is constructed of wooden boards overlaid by felt then tiles.
Each eaves space is only on one side of the
house and not connected with loft space above to allow circulation of air.
Now are you sure? I work as an aerial installer and I find that houses
of that type always have an easy means of getting cables from the small
side lofts to the main one. Usually the link is between the underside of
the roof boards and the sloping plasterboard of the bedrooms. Normally
this gap is packed with insulating material. Sometimes there are pieces
of plasterboard (etc) filling the gaps between the joists, but these can
simply be removed. If there is a tank in the top loft some of the pipes
might go down to the small lofts and that will show you the route.
I normally make a cable route through by pushing a length of drainrod
through the gap.

Bill

On Nov 1, 9:58*pm, fresia wrote:
We have a chalet style 1950s Scottish house with the second floor rooms contained within the roof space (not a loft conversion). There is a loft space above the rooms but also small loft spaces in the eaves on either side of the upstairs rooms accessed through small doors in the bedroom walls.

We want to insulate these spaces but are not sure what type of ventillation to install in them to prevent damp. The roof is constructed of wooden boards overlaid by felt then tiles. Each eaves space is only on one side of the house and not connected with loft space above to allow circulation of air. If we install tile vents, we presume there will not be the means for the air to circulate in these areas?

A further factor is that the soffits are made of concrete and therefore it is not possible to vent through these.

Any suggestions?

The normal solution is to insulate the ceilings and to put in air
bricks in the gables or tile ventilators in the roof to ventilate the
spaces.

Your problem is gonna be insulating the sloping bits of ceiling (if
there are any).

The boards you mention are called sarking boards. A Scottish
tradition.

fresia wrote:

We have a chalet style 1950s Scottish house with the second floor rooms
contained within the roof space (not a loft conversion). There is a loft
space above the rooms but also small loft spaces in the eaves on either
side of the upstairs rooms accessed through small doors in the bedroom
walls.

We want to insulate these spaces but are not sure what type of
ventillation to install in them to prevent damp. The roof is constructed
of wooden boards overlaid by felt then tiles. Each eaves space is only on
one side of the house and not connected with loft space above to allow
circulation of air. If we install tile vents, we presume there will not be
the means for the air to circulate in these areas?

A further factor is that the soffits are made of concrete and therefore it
is not possible to vent through these.

Any suggestions?

You can either insulate the ceilings and add some vents into the loft space
as others have suggested, or insulate between and under the rafters.

If going between rafters, you can either use wool (glass/sheeps) or celotex
type boards.

Usually, with non breathable sarking you would need 50mm of air space
between the top of the insulation and the underside of the roof covering -
and this space would need to be ventilated top and bottom on every rafter
run.

Your local Building Control inspector (or whatever they are called in
Scotland) should be able to advise - I would invite him round for tean and
biscuits - IME they ar eoften very helpful.

HTH

Tim
--
Tim Watts Personal Blog: http://www.dionic.net/tim/

"It would be better to live under robber barons than under omnipotent
moral busybodies."