Insulation under kitchen cupboards?

[Mercenary Keyboard Warrior]

Been working on some drafts etc on the kitchen and attached diner (no rad in kitchen) only heat convected from diner and I have now narrowed the main source of cold as coming from outside walls under the cabinets.

The cabinets are in an kind of long thin U arrangement and this corresponds with the outside walls, apart from one short section thats against internal wall.

Feeling round the bottom of the cabinets there is a noticeable cold draft, and also the tiled floor is really cold here and warms as you get further from the cabinets.

So I was thinking of adding some insulation, probably just some rockwool, and maybe then sealing along the bottoms of the under cabinet trims.

There will be some ventilation, eg up behind the cooker and out over the top of the cooker under the worksurface. Also where the mains water rises though the cabinet bottom etc. So limited, but there should it be needed.

Anyone know of any reason this wouldnt work. I know its still going to have some cold work its way through but my thought was to keep the direct cold draft from being able to leak directly, which should reduce convection pulling the cold out.

 

[SPG]

I did the same, never been or caused a problem in 2 years after having a new kitchen fitted.

 

[Glaucus]

what wall construction is it, the only thing you need to worry about is where the dew point is and can be mitigated with a vapour control barrier

https://www.homebuilding.co.uk/internal-wall-insulation/

 

[Mercenary Keyboard Warrior]

thanks guys

I wasn't going to insulate the wall directly, more like trying to fill the gap under the cupboards. I think I am going to get a roll of loft insulation, I need to top up a few areas up in the loft so needed some anyway.
If I get the 200mm deep it will just need fractionally compressing to sit in the gap under the cabinets, if I put it with just a minor gap at the front there will still be quite a gap at the back anyway (assuming I put it 30cm or so deep) so there will a decent air reservoir sitting behind the insulation, and as I said this will still have some limited access to gaps in a few places so it wont be isolated, just highly restricted.

 

[Buffman]

I recall reading someone on here doing similar. Surely there will be little draft unless you have holes in your walls?/floor?

And if it's plastered to a similar level as the rest of the walls in the room it won't make much (any?) difference?

 

[kinobestew123]

For there to be a draught, there must be holes in the wall where wind from outside is blowing in. Maybe check around all waste pipe exits near the sink, washing machine and dishwasher and also tumble dryer vent if you have one?

 

[Mercenary Keyboard Warrior]

I cant remember how the wall looks under the cabinets to be honest, but it was mentioned elsewhere that the plasterboard should not go to ground level, and that the skirting should cover this gap, but that most house builders upto a certain date around 2008 or so didnt as they didnt need to for the then current legislation
So what people say is that you get a draft from behind the plasterboard.

There arent any holes but there is certainly a draft, although it could just be cold air being pulled through due to heat rising

 

[kinobestew123]

Oh I see, I thought we were talking brick wall. Makes more sense then.

I don't see any harm in putting a tight fitting chunk of insulation just behind the plinth. I'd leave a large gap behind that though up to the wall.

 

[Mercenary Keyboard Warrior]

So i had a look in detail underneath last night as i was having to remove the in built dishwasher which has given up.
Its indeed as described, plasterboard down to about 1-1.5 inches above the ground, then nothing in effect sealing that to the floor.

So I am going to get the loft insulation, and fill the front of the void with that, pretty sure it should eliminate the draft and reduce the cold convection dramatically.

 

[Business Man]

I'm guessing you have a suspended timber floor? You will get a draft from between the wall and floor because plasterboard isn't supposed to be in contact with the floor and you don't usually have skirting behind units. You could use expanding foam to fill the void instead if you can reach to the back. While roll insulation would work my worry with it would be it would soak up any leak and you wouldn't know anything about it until it was too late.

 

[fastwunz]

If it is a timber suspended floor then our source of cold drafts is cold air through the air bricks surely? Dont, what ever you do, block then up