Garage conversion ceiling insulation

[JustinScot]

Hi,

We had our garage converted into a living room earlier this year and the room is considerably colder than the rest of the house.

There are 2 radiators that get hot and warm the room for about an hour but then the room is cold again and the rest of the house is still warm.

I have done the basic stuff like check for draughts but I can't find how or why it's getting cold.

When they built it I checked they put in insulation in the floor and walls.

Today I opened up the down lights to check if the ceiling has insulation and it does. But there is a 4 inch gap between the ceiling and the wool. See attached.

Would use the issue? How can I fill this.

Thank you

 

[foxhole]

Does it have its own roof or is it integral garage ?

 

[JustinScot]

Does it have its own roof or is it integral garage ?

It has its own pitched tile roof.

 

[foxhole]

It has its own pitched tile roof.

If you have access then you need to make sure you have around 300mm of insulation, though the more then better .
What type , size of wall insulation was used ?

 

[paulrockliffe]

The more you put in the colder the roof space will be, the more likely you are to get condensation. 300mm is in the territory for needing proper consideration of cross ventilation and given the history of the room in most cases there won't be any ventilation of the roof space at all.

If you have condensation dripping into wool insulation, it will sink to the bottom and never dry out.

 

[JustinScot]

If you have access then you need to make sure you have around 300mm of insulation, though the more then better .
What type , size of wall insulation was used ?

I don't have access to that part of the roof, the only way is I could see the wool is through the downlight holes. Is this normal to have the gap?

 

[JustinScot]

The more you put in the colder the roof space will be, the more likely you are to get condensation. 300mm is in the territory for needing proper consideration of cross ventilation and given the history of the room in most cases there won't be any ventilation of the roof space at all.

If you have condensation dripping into wool insulation, it will sink to the bottom and never dry out.

Are you saying this gap is for ventilation?

 

[paulrockliffe]

No, I've no idea what the gap is, though that sounds unlikely.

I was just pointing out the potential consequences of just stuffing as much insulation as possible into an unventilated cold roof space.

 

[paulrockliffe]

Just reread your post, you need ventilation above the insulation, so unlikely that your gap is for ventilation. Probably it's because GU10 bulbs get very hot, the non-LED ones anyway.

 

[foxhole]

Your power cables should not be insulated, you would need to cut a hatch to loft area to insulate.

 

[IT Minion]

As Paul says most down lights shouldn't be covered directly with insulation. They can overheat. I believe it's less of an issue with LEDs but the air gap is probably there on purpose. Effectively a dropped ceiling.

Which means you've got ventilation below your insulation for the lights, and you may need it above the insulation as well for the roof void. One stops your roof bursting into flames, the other stops it going soggy.