Cold outside wall and excess condensation

[dawniecarl]

We have a 3 bed semi and in both front bedrooms it feels much colder than the other rooms. Both rooms have radiators and laminated flooring. As you walk towards the window you can feel the floor become colder, the wall is cold to touch (is only backing paper painted I think) and every morning there is mega condensation! Is there something wrong with the outside wall?
I've read up about condensation so have no wet washing in there, and try to avoid all the other causes (bar stopping breathing!) This summer we had cavity wall insulation put in hoping this would help but not an iota of difference. Any help would be much appreciated.

 

[freddiemercurystwin]

What ventilation do you have? If you have very poor ventilation, additional insulation can exacerbate the problem.

 

[dawniecarl]

What ventilation do you have? If you have very poor ventilation, additional insulation can exacerbate the problem.

Just a vent in the corner of each bedroom. The small bedroom isn't even used. The condensation is annoying but its the cold I'm more concerned with! There's none in the downstairs living room which is the same wall.

 

[^woody^]

Common reasons why rooms on one side of a property feel colder are the direction they face (sunshine or prevailing weather) and whether the rads are properly balanced or if the thermostat downstairs shuts the heating off when downstairs is hot and not the upstairs

You've got insulation and ventilation so you may want to look at the heating to see if the rooms are being heated adequately

 

[JohnD]

the two front bedrooms?

could the outside wall be damp. e.g. from gutter or downpipe leaks?

do they have panelled or bay windows, which may be thin or non-standard construction?

how much loft insulation do they have above the ceilings?

be aware that water vapour is lighter than air, so will rise up from downstaitrs rooms if they contain it e.g. from cooking or wet washing.

 

[dawniecarl]

the two front bedrooms?

could the outside wall be damp. e.g. from gutter or downpipe leaks?

do they have panelled or bay windows, which may be thin or non-standard construction?

how much loft insulation do they have above the ceilings?

be aware that water vapour is lighter than air, so will rise up from downstaitrs rooms if they contain it e.g. from cooking or wet washing.

I think this is sounding more like it. Both rooms have a radiator - small box room has one right below window (granted its small but so is the room) and yet room never warms up, also our bedroom has a standard radiator same as living room downstairs yet living room warms up, our room never feels warm. I try to avoid drying washing inside at all costs and if so its at back of house downstairs.
We do have bay windows and when you knock on the wall under the window it sounds hollow (board?) Difficult to see the insulation in the loft as its been boarded prior to us buying the house. Its does have insulation. I'm no pro at any of this stuff. Just hoped you guys could point me in the right direction of solving the issue. Your advice and pointers are great, thanks and any other pointers are very much appreciated! Should I get soneone in to check the wall?

 

[big-all]

if your joists are up to standing on the measurement from ceiling below to on top off the covering should be around 230-250mm i suspect yours will be nearer half that so not up to any real load [15+22+100=137mm]

 

[JohnD]

Difficult to see the insulation in the loft as its been boarded prior to us buying the house.

pull up a board and have a look.

 

[alittlerespect]

Hi

The floor has always been cold, the issue is that the carpet would have provided a better insulation value and you would not have noticed the cold floor to the same degree as you do now.

With regard to the condensation - how bad it is will to a certain extent depend on the orientation of the building e.g. if your room is North facing it will be worse at times than a South facing room because of the temperature differential. The easiest solution would be to add a PIR insulated plasterboard to the offending walls, a general rule that I use is that each 25mm (1") of insulation reduces heat loss by around a half - so at the moment your U value/heat loss is around 2.8W/m2C (perhaps even worse) adding 25mm insulation would reduce the heat loss to around 1.4W/m2C and adding 50mm insulation would reduce the heat loss to around 0.7W/m2C. Also PIR is fairly vapour resistant and you would not have to worry about installing a vapour barrier or have any problems with condensation between the interface between insulation and the wall.

Obviously the thickness of the insulating plasterboard you use will depend on site conditions, but other contributers to this forum have noticed considerable improvement with an insulation thickness of 25mm. As the saying goes 'the choice is yours'

Regards

 

[mointainwalker]

@ a little respect

That should be a K and not C in the formula.

The C is wrong and , moreover, makes it possibly confusing.