Cold bedroom, and loft insulation

[nervous123]

A back bedroom is exposed on 3 sides and hence much colder than rest of house. I have checked in the loft and there are insulation rolls laid out above the room (not sure if 27cm, but not visibly less than rest of the loft's insulation. If anything - even more)

However my query is that there are no floorboards/chipboard ontop of the insulation. Would that create heat loss? -- If we had boards put down ontop of the insulation would that make a big difference?

Thanks a lot

 

[JohnD]

no

but measure and tell us how thick the insulation is.

It will be those three external walls you mention. Do you have cavity wall insulation?

 

[nervous123]

The walls are old, so I doubt it.

They are also very very cold to the touch.

Will external render help at all?

The room is so small that internal insulation will not be appreciated

 

[JohnD]

if you measure the thickness of the outside walls (at a window) is it about 9 inches, or about 13 inches? Cavity wall insulation is subsidised this year, so very cheap.

external render will not help.

It is possible, but expensive, to insulate walls externally, but they will then need cladding or render over it.

What size is the room, what size is the radiator, is the radiator "too hot to hold for long" all over?

 

[nervous123]

if you measure the thickness of the outside walls (at a window) is it about 9 inches, or about 13 inches? Cavity wall insulation is subsidised this year, so very cheap.

All 3 walls appear to be approx 9.5 inch. Does that mean they are single skin in which case we cant do cavity wall insulation?

What size is the room, what size is the radiator, is the radiator "too hot to hold for long" all over?

The room is 2.65 W x 2.70 D X 2.65 H., the rad is an old single panel 173 x 45 (odd dimensions I know) and it does get very hot. A BTU calculator says we would need no more than 3325 (with details as 'single glazed' and 'exposed' - it does have double glazing albeit not especially good ones).

 

[JohnD]

Yes, that is a single brick solid wall plus plaster. Internal insulation would add about two inches thickness.

I should think your rad has a nominal output in the region of 1400W (roughly 4800 BTU) as it is similar in size to this one

http://www.screwfix.com/p/kudox-premium-type-11-compact-convector-radiator-white-500-x-1600mm/66553

although modern rads usually have fins on the back which increase the power a bit.

Your rad sounds a fair size, you could increase the output by changing it for a double one of the nearest modern size e.g. this one is nominal 2137W
http://www.screwfix.com/p/kudox-premium-type-21-compact-convector-radiator-white-500-x-1800mm/33055
or you could possibly fit one 600mm high for a bit extra. These big double rad are rather heavy. You may need to adjust the pipework to fit. This will be easier if you can lift the floorboards next to the rad to get at the pipes.

I think you will still have a problem with the room getting colder during the night due to heat loss through the walls.

 

[nervous123]

Many thanks for your advice/help, John.

I think we will get a new rad, although as you say, heat loss through the walls will no doubt continue to be a problem.

The floor is up at the moment anyway for other reasons so prob a good time to do it.