Insulated Sectional Garage Door - Better for Bedroom Above?

ThisIsWeird

Sean, you can consider the garage as effectively being an 'outdoor' space; it doesn't have any heating in there, so will closely follow the outside temperature. It'll gain a little heat from the house itself, but should still effectively be considered an outdoor space.

Adding insulation to the garage walls - or door - won't change this to any significant degree; it'll still be an unheated space, so will remain close to the outside temp.

Adding insulation to the garage ceiling might help the bedroom above, but only if the required insulation for that garage ceiling/bedroom floor was inadequately designed (unlikely - they would be following BRegs) or poorly installed (possible). For the latter scenario, I cannot see it helping if you add an additional layer of insulation to the garage ceiling, as the issue - poorly-installed insulation in the ceiling void - would likely remain. Ie, if the cold bedroom is being caused by large gaps in the void insulation, which is allowing cold air to flow through that space, then adding a layer of Celotex to the underside of that draughty void is not going to help.

At the moment, of course, you simply do not know what the cause of this lower temperature is, so I'd certainly not start flinging insulation around yet. It could be:

That room is more North-facing?

The radiator isn't getting as hot?

The room has more than one external wall?

There is a draught coming in from under the skirting boards?

Other stuff I cannot think of?

And have you actually measured the temps of the rooms to see how they truly compare?

Since you - very understandably - don't want to wreck the floor by prising up the glued-and-screwed boards, then you won't know if poorly-installed insulation in that void is actually the cause. The only other way to find out is to rip down the garage ceilings. I suspect that isn't much better?

Of course, you could try screwing a 2" thick layer of rigid insulation to the garage ceiling and seeing if that helps, but the comparison would need to be done on equal terms - ie similar outdoor temps, wind speeds, etc. And there will remain a good chance that it'll have no effect at all.

Although not as effective - as the layer will be much thinner - adding a layer of insulation to the top of the bedroom floor before relaying the carpet underlay will have a benefit, if the floor is cold. That would have a guaranteed benefit - if the floor is currently not up to standard. Whereas adding a layer to the garage ceiling might help, or it might not. The simplest stuff to use would be fibre-board underlay as used for many laminate floorings. This comes in 'rigid' panels around 8mm thick, and should help. Good chance your bedroom door will require trimming, of ocourse. If doing this, sleal between each board, and - more importantly - around the room perimeter to make sure the skirting boards are airtight.

I'd have a look at the other possible causes first. If you get a breezy day, then go around the skirting-floor join with a smoking taper, and see if there are any signs of a breeze coming through. Or, make sure the windows are fully shut, close the bedroom door, and try the same at the keyhole and around the door-frame gap.

Mutton_Geoff

You can confirm it just by looking at them. How thick are they? Are they external? Are they plain brick or proper plasterboard walls like the rest of the house?

naf123

It's not worth spending 2k just to make one room a few degrees warmer . 

Why don't you convert the garage into a office or something and put central heating in there . Then the bedroom will be warmer ! 

seanfos

Thanks again all, lots to think about. The garage is block interior with brick exterior, but I don’t know if they put insulation in the cavity. We don’t want to convert the garage to an interior space as it is a workspace for me when DIYing. We have spotted an issue with the bedroom window where one side is leaving a gap when closed, so first port of call is waiting for the developer's window company to sort that and see what difference that makes to temperature.  Then, if needed, a thermal imaging camera or survey to reveal any potential cold spots which I will follow up with the developer also. I'll bear in mind the potential solutions suggested here if I need to go back to them

Sean

ThisIsWeird

A thermal imaging camera is a good call. Haven't used one myself yet, but it does sound like the ideal tool for such a task.

Keep the thread updated, please, with what you find

EmmyLou30

Very similar situation in our 1990's house, one bedroom above a garage so it has 3 external walls, a block of cold air underneath it in the garage via a draughty up and over door and whatever passed for adequate insulation when the house was built between the ceiling/floor. That bedroom was always harder to heat and we generally left the door open so it could get heat off the landing to balance it out.

Recently got a sectional garage door, thick and insulated (though obviously not 'sealed' round the frame it's a lot better than the old door with minimal gaps). It's made a big difference. The garage is a much more static temp so stayed cool in summer (used to get really hot being south facing) which helped keep the bedroom cooler and now come winter it's noticeably not freezing cold out there at all which has meant the bedroom is easier to heat. It wasn't the reason we did it, the old door was rotting and falling off the runners and not very secure, but the improvement gained by having a modern insulated door have been way more than I expected. 

seanfos

I will keep updating. I'm hoping the window will make a good difference

I forgot to answer some of the questions earlier.  We have little digital thermometers in most bedrooms, so are able to directly compare temperatures with those, but just walking into the room above the garage you can instantly feel the difference. The bedroom has one window which is north facing and three external walls so I do expect some difference. There is one radiator and it is under the window. We have the TRV set to max and all other upstairs rooms are set halfway. The radiator does feel very warm but we have to leave it on all night at the moment to stop the temperature falling too far

Sean

seanfos

EmmyLou30 said:

…but the improvement gained by having a modern insulated door have been way more than I expected. 

Thank you, good to hear other people’s experiences

Sean

Nearlyold

EmmyLou30 said:

Very similar situation in our 1990's house, one bedroom above a garage so it has 3 external walls, a block of cold air underneath it in the garage via a draughty up and over door and whatever passed for adequate insulation when the house was built between the ceiling/floor. That bedroom was always harder to heat and we generally left the door open so it could get heat off the landing to balance it out.

Recently got a sectional garage door, thick and insulated (though obviously not 'sealed' round the frame it's a lot better than the old door with minimal gaps). It's made a big difference. The garage is a much more static temp so stayed cool in summer (used to get really hot being south facing) which helped keep the bedroom cooler and now come winter it's noticeably not freezing cold out there at all which has meant the bedroom is easier to heat. It wasn't the reason we did it, the old door was rotting and falling off the runners and not very secure, but the improvement gained by having a modern insulated door have been way more than I expected. 

We fitted Hormann LPU67 Thermo sectional doors to the garages under two of the upstairs bedrooms, and have definitely noticed a difference as above, in our case we've found the sealing round the doors to be very effective with no discernible draughts. We had previously insulated the up and over doors which worked to an extent but nowhere near as well as the new doors. 

seanfos

Thank you, great to hear of another experience. The window company should be here tomorrow to fix the gap issue, so we will see what difference that makes for step one

Sean