Why is one of my rooms so cold?

VT41

Recently bought a place and one of my rooms is far colder than the rest of the place. I've tried to spot the cause and will detail what i've looked into. Firstly in said room we've had some mould in the corner of the room and I realise I need to increase air flow/ventilation to reduce humidity levels. I've purchased a de-humidifer which should aid reducing humidity levels. 

I also had blinds fitted and Hilarys mentioned the windows aren't perfectly 'plum' which is why one side of the (double glazed window) emits light through it a bit more. 

The door to this room is a very tight close and there is a fairly large gap between the floor and bottom of the door, which i've blocked using a draught excluder. 

The carpet to be quite blunt feels like i'm walking on hay, (image below) -  I will get this replaced.

1. The radiator heats up well enough - after holding your hand on it for a while it becomes too hot to touch; so I believe it's working ok.
2. As the door isn't perfect fit - would this be the cause of it all?
3. Could the carpet be the cause not retaining heat?
4. Is it simply the radiator isn't good enough for the size of the room? ( 13'7 * 12'7)

[Deleted User]

Couldn't get your photo links to show any images.

* Are we talking about ground floor or first floor - so concrete or wooden floors ?
* Carpet, if it or the underlay is old and in need of renewing that could well improve the retained heat, a lot is lost from the ground. Rugs, in the interim could help.
* Gaps under the door - possibly causing the problem.
* Is the heating on enough to actually bring the house to a comfortable ambient temperature to start with - or does that need addressing - if it's already a cold room that could be the issue.

Soot2006

Have you been able to make the room really warm?

I have a dormer room with very poor insulation that was always a bit colder than other rooms. What happens is that because it's harder to heat, by the time the house thermostat hits the required temps and turns off the boiler, that one room was colder than the rest.  The only way I could reliably heat it was by adding in my little space heater and giving it an extra hour after boiler had switched off.

The obvious long-term solution is always insulation/heat retention. So a new roof with insulation is on the wish list, but in the meantime I put in a new window (the window was 1990s and the fittings had deteriorated) and also a larger, higher output radiator -  the difference is enormous. Now the rooms heats more quickly and retains more heat, compensating for some of the loss through the roof. I haven't needed the little space heater this winter yet and we've had some cold nights.

Norman_Castle

Hessian carpet on a wooden floor? How can a window let more light in from not being plumb? Do you mean the openers arent sealing properly?

Doozergirl

Does the room have exterior walls on the north?  

TELLIT01

Norman_Castle said:

Hessian carpet on a wooden floor? How can a window let more light in from not being plumb? Do you mean the openers arent sealing properly?

Or do you mean there is a gap between the window frame and the wall? 

"The radiator heats up well enough - after holding your hand on it for a while it becomes too hot to touch; so I believe it's working ok."  I wouldn't be able to hold any of my radiators 'for a while' before they became too hot to touch.  Have you tried bleeding that radiator?

another_casualty

What kind of property ? What kind of flooring ?

NSG666

As you've said you need to increase air flow/ventilation so don't bother about the gap at the bottom of the door - if practical leave it open as much as possible to allow air circulation. The door might have swelled slightly from the damp in the room.

The dehumidifier will help a lot especially if it can be run at the same time as the heating is on.

You say you've recently bough it so give it time to dry out before looking too much further although you could feel to see whether the radiator is getting hot in the middle and at the bottom between mid-way between the two valves.

Window reveals are often not level or plumb but shouldn't cause any issues unless you can feel draughts due to poor window installation.

DRP

Sounds like draughts are an issue at the window and possibly at the door, although you've not specified if this is in external door.

Get the window fixed and/or get some caulk or foam trim to go around any gaps
Caulk any gaps at floor level
?door - don't have enough information to advise
?room - bedroom/kitchen/front room/downstairs/upstairs/loft - the solution depends on which it is

Bendy_House

Probably a combination of causes, but that rad ain't big.

You are having the carpet replaced? Cool. While it's up, seal between every floorboard, and around - and under - the skirting boards. Use cheap brown frame sealant. Draught-proof that floor.

If there is enough of a gap under your door to allow it to swing over a slightly raised floor (that's a joke!), then also lay down 8mm low-density fibreboards all over the floor. This is used as underlay for laminate flooring - check out Wickes and others. Stick it down (the frame sealant will do this), and also seal with a bead between each sheet, and against the wall. Stagger the sheets like brickwork. That'll super-draught-proof your floor, and also add a small extra level of insulation for little cost.

Fix your window.

The door doesn't matter, but I guess you will be replacing it anyway? I say it 'doesn't matter', because a draught needs a 'path' - an in and an out. By sorting the floor and the window, you've cut off that path.

If you can bear to do it, line the insides of the external walls with insulated plasterboard, even the thinnest 35mm stuff. This will transform the insulation level of that room, and should stop any future condensation and mould deed.

What's above the ceiling?

After doing all this, you probably won't have to increase the size of that rad. Fixing the draught is the simplest, and probably the most effective, part of this process.

Would I swap that rad? Not unless it needed it. It'll do the job for 75% of the year, and when it doesn't, put a 1.5kW oil-filled rad in there. A new CH rad would cost ~£200 fitted, so that money will provide for quite a few years of running an oil-filled rad for a couple of hours each evening over winters.

coffeehound

ur welcome