Can I get some advice from those of you that have not had full loft
conversions but still use a loft for rec. In my case it's model
railroading...

I have a large layout (just track & stock only atm) in my loft which
is a modern truss roof with a layer of black cloth type material
between the roof spars and the tiles on the outside.

My problem is probably a common one: Temperature.

In the winter with a small electric heater and an open hatch I can
keep temperatures to above 5c at worst overnight and make them
habitable during the day. It's during summer I have the problems.
Temperatures will reach 40c up there on the warmest days and I am
concerned about long term damage to stock and buckling of track, not
to say it is totally impossible to work up there at those sorts of
temps.

My options seem to be

1) Roof light to let heat out. Expensive and may not work well enough
to be worth the outlay. Plus I have to remember to open it !!!
2) Portable A/C unit but I read that the cheaper ones need good
ventilation which I obviously don't have.
3) Some sort of insulation in the roof between the trusses to keep the
temps down in summer and up in winter. Again, expensive and not a DIY
option as far as I know. One loft extension company warned me that the
material has to be a special sort to prevent the roof sweating.

I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I'm dreading another summer of hobbying in a sauna!

Gary Brown wrote on 10/05/2005 :
My problem is probably a common one: Temperature.

In the winter with a small electric heater and an open hatch I can
keep temperatures to above 5c at worst overnight and make them
habitable during the day. It's during summer I have the problems.
Temperatures will reach 40c up there on the warmest days and I am
concerned about long term damage to stock and buckling of track, not
to say it is totally impossible to work up there at those sorts of
temps.

An opening Velux style window would fix most of your heat problems in
the summer. I have no idea what to suggest for the insulation problem.

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.org

I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I'm dreading another summer of hobbying in a sauna!

Could you install a couple of fans in the "ends" one end blowing out, and
the other in?

I have no experience of doing this, but if they had enough flow, you would
be blowing out hot air, and sucking in cold (well, outside temperature!) air

Maybe install multiple fans, keeping to the in one end, and out the other
idea?

Sparks...

"Sparks" wrote in message
.. .
I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I'm dreading another summer of hobbying in a sauna!

Could you install a couple of fans in the "ends" one end blowing out, and
the other in?

I have no experience of doing this, but if they had enough flow, you would
be blowing out hot air, and sucking in cold (well, outside temperature!)
air

Maybe install multiple fans, keeping to the in one end, and out the other
idea?

Sparks...
Sparks??? What are you, simple.You can not cool a loft using fans all that
you do is stir the air.
Velux windows even when fitted on both slopes of the roof do not adequately
cool the loft.
After many summers living in a loft and suffering unbearable tempuratures
the only correct way is to stop the approx 6 kw per metre of heat reaching
the inside of the roof.
Celotex or Kingspan fitted between the rafters 50mm with air gap between
tiles and insulation will work. remember to tape the joins to complete the
job.

"sploop" wrote in message
...

"Sparks" wrote in message
.. .
I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I'm dreading another summer of hobbying in a sauna!

Could you install a couple of fans in the "ends" one end blowing out, and
the other in?

I have no experience of doing this, but if they had enough flow, you
would be blowing out hot air, and sucking in cold (well, outside
temperature!) air

Maybe install multiple fans, keeping to the in one end, and out the other
idea?

Sparks...

Sparks??? What are you, simple.You can not cool a loft using fans all that
you do is stir the air.

sploop?? are you simple, or cant you read?

I did not suggest just using fans to stir the air as you blurted out, I
suggested installing fans IN the walls, to the OUTSIDE of the building, one
drawing air into the loft from outside, and the other blowing the hot air
out the other end of the building.

Sparks...

In message , Gary Brown
writes
Can I get some advice from those of you that have not had full loft
conversions but still use a loft for rec. In my case it's model
railroading...

I have a large layout (just track & stock only atm) in my loft which
is a modern truss roof with a layer of black cloth type material
between the roof spars and the tiles on the outside.

My problem is probably a common one: Temperature.

My options seem to be

1) Roof light to let heat out. Expensive and may not work well enough
to be worth the outlay. Plus I have to remember to open it !!!

Can you get automatic openers, like they use in Greenhouses I wonder?

how about a thermostatically operated extractor fan?

3) Some sort of insulation in the roof between the trusses to keep the
temps down in summer and up in winter. Again, expensive and not a DIY
option as far as I know. One loft extension company warned me that the
material has to be a special sort to prevent the roof sweating.

Nah, this sort of thing is quite DIYable, insulation slabs are fitted
either between the rafters, or over them.Nothing special about the
materials. You need to leave enough space behind the insulation for
there to be ventilation to stop condensation that is all.

Don't know how effective it would be though at heat reduction.

. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I take it you mean gable ends. A decent sized extractor fan highish up
in the gable at one side, with a vent in the other may help a fair bit.


--
Chris French, Leeds

Gary Brown wrote:

My options seem to be

1) Roof light to let heat out. Expensive and may not work well enough

If you DIY, you could do it for 200 - 300 ish. Would probably help a
fair bit.

2) Portable A/C unit but I read that the cheaper ones need good
ventilation which I obviously don't have.

AC would be most useful if you had some decent insulation in the first
place. All A/C (good or bad) needs a place to vent the heat (and water)
- they don't generate "cold" as such - just pump heat from one place to
another.

3) Some sort of insulation in the roof between the trusses to keep the
temps down in summer and up in winter. Again, expensive and not a DIY

Expensive ish - depending on the size of loft you could probably do it
very well for 400 to 600. or moderately well for say 200 to 300. Even
moderate insulation would be a huge advance on what you currently have
though.

option as far as I know. One loft extension company warned me that the

Very much is DIY'able - not a difficult job.

material has to be a special sort to prevent the roof sweating.

The material is not that important (but rigid foil covered PIR Foam
panels would be simplest to use), but you need to ensure that the roof
woodwork can still get ventilation so that it does not rot. This may
mean needing to install soffit and ridge vents if you fully enclose the
internal surface of the rafters.

I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

A window in one/both of the gable ends may work quite well - does not
matter if the view is only of the adjacent gable, since what you are
after is ventilation not a nice sunset.

I'm dreading another summer of hobbying in a sauna!

Perhaps you should ditch the trains and install some nearly naked
Sweedish lasses instead - may make the sauna seem far more appealing ;-)

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Wed, 11 May 2005 02:42:04 +0100, John Rumm
I'm dreading another summer of hobbying in a sauna!

Perhaps you should ditch the trains and install some nearly naked
Sweedish lasses instead - may make the sauna seem far more appealing ;-)


Now that's the best selection of all.

Thanks for all the others, I was wanting to cover the inside face of
the roof rafters anyway for appearance and to bounce to light around
better. Was thinking about 6mm MDF painted white as being lightweight,
easy to cut and shape.

Need to investigate the insulation material more though. I think
that's my favorite option as it seems the most DIYable without cutting
holes in any walls!

On Tue, 10 May 2005 22:33:45 +0100, Gary Brown
wrote:

Can I get some advice from those of you that have not had full loft
conversions but still use a loft for rec. In my case it's model
railroading...

I have a large layout (just track & stock only atm) in my loft which
is a modern truss roof with a layer of black cloth type material
between the roof spars and the tiles on the outside.

My problem is probably a common one: Temperature.

In the winter with a small electric heater and an open hatch I can
keep temperatures to above 5c at worst overnight and make them
habitable during the day. It's during summer I have the problems.
Temperatures will reach 40c up there on the warmest days and I am
concerned about long term damage to stock and buckling of track, not
to say it is totally impossible to work up there at those sorts of
temps.

My options seem to be

1) Roof light to let heat out. Expensive and may not work well enough
to be worth the outlay. Plus I have to remember to open it !!!
2) Portable A/C unit but I read that the cheaper ones need good
ventilation which I obviously don't have.
3) Some sort of insulation in the roof between the trusses to keep the
temps down in summer and up in winter. Again, expensive and not a DIY
option as far as I know. One loft extension company warned me that the
material has to be a special sort to prevent the roof sweating.

I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I'm dreading another summer of hobbying in a sauna!


I'd kingspan the whole place, this is an easy DIY job.

Put the kingspan tightly between the rafters, leaving a 50mm gap at
the back for ventilation. The ventilation gap needs to be exposed to
the outside. You should have soffit vents so thay should vent the gap.

The more kingspan you can put in the better the job will be. You need
to ensure there are no gaps. This will keep the heat out and in.

Kingspan can be cut with a bread knife, and just jamed into the gaps.
No nasty rockwool type fibres to worry about either.

Rick

On Wed, 11 May 2005 07:55:22 GMT, Rick wrote:


I'm dreading another summer of hobbying in a sauna!


I'd kingspan the whole place, this is an easy DIY job.

Put the kingspan tightly between the rafters, leaving a 50mm gap at
the back for ventilation. The ventilation gap needs to be exposed to
the outside. You should have soffit vents so thay should vent the gap.

The more kingspan you can put in the better the job will be. You need
to ensure there are no gaps. This will keep the heat out and in.

Kingspan can be cut with a bread knife, and just jamed into the gaps.
No nasty rockwool type fibres to worry about either.

Rick

Can you point me towards an explanation of sofit vents?

I'm assuming you mean the area where the roof meets the outside walls.
I had always assumed there was sufficient ventilation there anyway as
I can see daylight in a few places already (never been over that far,
ingrained fear of spiders!!!).

Gary Brown wrote:

Need to investigate the insulation material more though. I think
that's my favorite option as it seems the most DIYable without cutting
holes in any walls!

The rigid foam types are the simplest to use in these cases. Trade names
like Celotex, or Kingspan are often quoted. The web sites for these
companies also have good information on their use for your application.
The generic name is PIR or eurothane foam. Have a look at:

http://www.secondsandco.co.uk/


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Gary Brown wrote:

Can you point me towards an explanation of sofit vents?

I'm assuming you mean the area where the roof meets the outside walls.
I had always assumed there was sufficient ventilation there anyway as
I can see daylight in a few places already (never been over that far,
ingrained fear of spiders!!!).

|
\
\
__\
| ^
| Soffit
|

i.e. the horizontal board that fills the gap between wall and edge of
roof. Note that not all buildings have them - if you can see the ends of
the rafters from outside of the house then you may not.

If your soffits are made from wood or PVC or something drillable then
you can retrofit vents quite simply:-

http://www.screwfix.com/app/sfd/cat/...68936&ts=13904
http://www.screwfix.com/app/sfd/cat/...13815&id=19804
http://www.screwfix.com/app/sfd/cat/...13815&id=12437


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article , John
Rumm writes
Gary Brown wrote:

Need to investigate the insulation material more though. I think
that's my favorite option as it seems the most DIYable without cutting
holes in any walls!

The rigid foam types are the simplest to use in these cases. Trade
names like Celotex, or Kingspan are often quoted. The web sites for
these companies also have good information on their use for your
application. The generic name is PIR or eurothane foam. Have a look at:

that's "urethane"
(unless you know of some new european variety)
--
Tim Mitchell

On Wed, 11 May 2005 08:31:51 +0100, Gary Brown
wrote:

On Wed, 11 May 2005 02:42:04 +0100, John Rumm
I'm dreading another summer of hobbying in a sauna!

Perhaps you should ditch the trains and install some nearly naked
Sweedish lasses instead - may make the sauna seem far more appealing ;-)


Now that's the best selection of all.

Thanks for all the others, I was wanting to cover the inside face of
the roof rafters anyway for appearance and to bounce to light around
better. Was thinking about 6mm MDF painted white as being lightweight,
easy to cut and shape.

Need to investigate the insulation material more though. I think
that's my favorite option as it seems the most DIYable without cutting
holes in any walls!

I assume by modern loft, you have the W shape supports, and all the
bits of timer look very small. These type of roofs work well, but you
can't mess with them much before they loose lots of strength. A bit of
flooring, and a railway track is not too much weight, but 6mm of MDF
on the slopes might work out to be one heck of a lot more weight than
you first imagine. If you do do this use screws, not nails, the
vibrations of hammering are not always usefull.

The kingspan is sliver, any more than a strip light up there and you
will need sunglasses. I am putting it on my roof, and its doing my
elese in when the sun reflects.

Rick

Gary Brown wrote:
Can I get some advice from those of you that have not had full loft
conversions but still use a loft for rec. In my case it's model
railroading...

I have a large layout (just track & stock only atm) in my loft which
is a modern truss roof with a layer of black cloth type material
between the roof spars and the tiles on the outside.

My problem is probably a common one: Temperature.

In the winter with a small electric heater and an open hatch I can
keep temperatures to above 5c at worst overnight and make them
habitable during the day. It's during summer I have the problems.
Temperatures will reach 40c up there on the warmest days and I am
concerned about long term damage to stock and buckling of track, not
to say it is totally impossible to work up there at those sorts of
temps.

My options seem to be

1) Roof light to let heat out. Expensive and may not work well enough
to be worth the outlay. Plus I have to remember to open it !!!
2) Portable A/C unit but I read that the cheaper ones need good
ventilation which I obviously don't have.
3) Some sort of insulation in the roof between the trusses to keep
the
temps down in summer and up in winter. Again, expensive and not a DIY
option as far as I know. One loft extension company warned me that
the
material has to be a special sort to prevent the roof sweating.

I can't see any other options but has anybody else had my problem and
actually solved it? I don't mind throwing a bit of money at it for a
workable solution. BTW, dormers are out for appearance reasons and
both loft 'ends' face onto the sides of other houses (we are a 3 bed
detached).

I'm dreading another summer of hobbying in a sauna!

Firstly insulate.
2nd, install 2 fans or 2 windows and open them: the air will run right
through. 1 isnt anything like as effective.

NT

sploop pretended :
Velux windows even when fitted on both slopes of the roof do not adequately
cool the loft.
After many summers living in a loft and suffering unbearable tempuratures the
only correct way is to stop the approx 6 kw per metre of heat reaching the
inside of the roof.
Celotex or Kingspan fitted between the rafters 50mm with air gap between
tiles and insulation will work. remember to tape the joins to complete the
job.

Perhaps not, but from personal experience just one brought the
temperature of my loft down to bearable levels in mid-summer even
before the insulation went in. This depended on a good flow of air
being drawn in from the rest of the house (window or door open).

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.org

Tim Mitchell wrote:

that's "urethane"
(unless you know of some new european variety)

;-) thought it looked wrong when I typed it, but then got distracted
before trying the spell checker!

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Harry Bloomfield wrote:
sploop pretended :
Velux windows even when fitted on both slopes of the roof do not
adequately
cool the loft.

in my experience they make a dramatic difference, though there must be
through flow. (For some reason people seem to want to arrange them to
minimise through flow.) Whether its enough is another matter: on a 95
degree day, few things are enough.


NT


Perhaps not, but from personal experience just one brought the
temperature of my loft down to bearable levels in mid-summer even
before the insulation went in. This depended on a good flow of air
being drawn in from the rest of the house (window or door open).

On Wed, 11 May 2005 17:27:49 GMT, Rick wrote:

On Wed, 11 May 2005 08:31:51 +0100, Gary Brown
wrote:


Thanks for all the others, I was wanting to cover the inside face of
the roof rafters anyway for appearance and to bounce to light around
better. Was thinking about 6mm MDF painted white as being lightweight,
easy to cut and shape.


I assume by modern loft, you have the W shape supports, and all the
bits of timer look very small. These type of roofs work well, but you
can't mess with them much before they loose lots of strength. A bit of
flooring, and a railway track is not too much weight, but 6mm of MDF
on the slopes might work out to be one heck of a lot more weight than
you first imagine. If you do do this use screws, not nails, the
vibrations of hammering are not always usefull.

I was planning to use my electric staple gun which should have ample
strength to hold the board if enough staples are used.

I doubt the weight is an issue, given that any roof has to be able to
support 6" of snow without collapsing and snow is very heavy. Plus
the weight is acting at a 45deg angle and is therefore reduced in the
down direction as well.

The only thing I am unclear on is how far to go for vapour barrier
purposes and exactly how to deal with this issue.

On Fri, 13 May 2005 08:12:35 +0100, Gary Brown
wrote:

On Wed, 11 May 2005 17:27:49 GMT, Rick wrote:

On Wed, 11 May 2005 08:31:51 +0100, Gary Brown
wrote:


Thanks for all the others, I was wanting to cover the inside face of
the roof rafters anyway for appearance and to bounce to light around
better. Was thinking about 6mm MDF painted white as being lightweight,
easy to cut and shape.


I assume by modern loft, you have the W shape supports, and all the
bits of timer look very small. These type of roofs work well, but you
can't mess with them much before they loose lots of strength. A bit of
flooring, and a railway track is not too much weight, but 6mm of MDF
on the slopes might work out to be one heck of a lot more weight than
you first imagine. If you do do this use screws, not nails, the
vibrations of hammering are not always usefull.

I was planning to use my electric staple gun which should have ample
strength to hold the board if enough staples are used.

I doubt the weight is an issue, given that any roof has to be able to
support 6" of snow without collapsing and snow is very heavy. Plus
the weight is acting at a 45deg angle and is therefore reduced in the
down direction as well.

The only thing I am unclear on is how far to go for vapour barrier
purposes and exactly how to deal with this issue.

For the VB, take a look in the kingspan / celotex websites, they have
some nice drawings.

Rick