Took the kick boards off - how am I going to seal this up?

[Sparrowhawk]

It's draughty at foot level in the kitchen so I took the kick boards off.

 

There were a couple of bits of wood piled up in the corner which I hooked out with a hammer.

 

 

On the outside there is an air brick at this point (single clay brick size) so I was expecting something. But perhaps an airbrick with a grille that I could tape over. This is an all-electric kitchen, no gas appliances.

 

The bottom of the hole has plastic sheet on it (damp proof course?).

I tapped the top of the hole with a hammer. The top is thin plaster. It's taller than it looks.

 

 

How am I going to seal this up? It's behind a corner fitted unit. Lying on the floor it takes my outstretched arm plus a 15" hammer to reach the closest edge of the hole.

 

I can't take the bottom out of the kitchen unit as the fixings holding the carcass together are on the outside butting up to the neighbouring units.

Is cutting an access hatch in the bottom/back of the kitchen cupboard the only way? And then the best approach to cut PIR board to fit and tape the edges?

 

 

Bonus question: is this how the sink waste is meant to be secured into the drain?

 

 

[ProDave]

I would empty the contents of an expanding foam gun into that hole.

 

No that's not how you connect a drain but that will be equally awkward to fit properly with the units in place.

[gambo]

26 minutes ago, ProDave said:

I would empty the contents of an expanding foam gun into that hole.

 

No that's not how you connect a drain but that will be equally awkward to fit properly with the units in place.

Any specific expanding foam you would use? I may have a similar issue given how cold it's inside one of the units. When I had similar hole behind skirting I put a piece of xps (leftover) then exp foam around it.

[Sparrowhawk]

32 minutes ago, ProDave said:

I would empty the contents of an expanding foam gun into that hole.

 

No that's not how you connect a drain but that will be equally awkward to fit properly with the units in place.

 

The expanding foam cans I've used (gun-grade & not) have to be held near-vertical to work. Is there one that will work on its side under the units?

[ProDave]

I wonder if you could do it from outside through the holes in the air brick?  At worst case enlarge say 2 of them, one at each end with a drill to get the gun nozzle through

 

Might help to have an observer inside directing the squirting.  (having typed that I could see how that could go wrong......)

[dnb]

16 minutes ago, Sparrowhawk said:

The expanding foam cans I've used (gun-grade & not) have to be held near-vertical to work. Is there one that will work on its side under the units?

A long bit of thin hose used as an extension on the foam gun would work. But have it attached to a long stick so you can manoeuvre it or hold it still as needed.

[crispy_wafer]

get a length of small bore hose from an automotive shop, attach to end of gun, it might want to curl/coil up so would using a bamboo cane as a splint might help...  Just a thought.

Edited January 21, 2023 by crispy_wafer

[Redbeard]

The problem with using a long extension tube is that it slows the flow very significantly, so the tendency (on full pressure) to blow in and 'stick' is lost, and you get a lot of falling back out.
 

Could you not open out more on the outside, weasel a bit of board over the hole on the inside, then fill back towards the outside before finishing with brick or whatever the external skin is?

 

As far as the drain connection goes I wonder (if you could let off the bracket on the horizontal run) whether you could get a 110mm stop-end, drill a hole in it and shorten the 'pipe end' so that you can slot it up onto the 40mm waste, then down into the rubber of the socket end. Then a finger-full of silicone to seal, if you feel the need to seal.

[Sparrowhawk]

3 minutes ago, Redbeard said:

The problem with using a long extension tube is that it slows the flow very significantly, so the tendency (on full pressure) to blow in and 'stick' is lost, and you get a lot of falling back out.

 

That's my experience when using a 30cm extension tube with Soudal Flexible Expanding Foam Gun Grade. It changes the texture of the foam and it doesn't skin over in the same way.

 

3 minutes ago, Redbeard said:

Could you not open out more on the outside, weasel a bit of board over the hole on the inside, then fill back towards the outside before finishing with brick or whatever the external skin is?

 

I think this way which you and @ProDave have suggested is the most practical approach and most likely to succeed. The outside of the house is rendered so the air brick can be rendered over eventually. Though I must take the tape off the air brick tomorrow and check the two line up!

[Sparrowhawk]

The deed is done

 

I had to wait until the weather warmed up to be above the "min 5C" temperature for the foam, and used a disposable Soudal can as the straw it came with was small enough to fit through the air brick holes without drilling them out. It took the whole can to get it to seal this plus back to the airbrick so I imagine the cavity has a bit of fill too.

[Sparrowhawk]

Hard to measure the impact as it's warmer outside this morning than yesterday so is the 2C difference due to that or no hole in the wall, but the lack of air movement in the kitchen is noticeable.

[Radian]

Is that a hard plastered wall that stops short of the floor or dry-lining?

[Sparrowhawk]

2 hours ago, Radian said:

Is that a hard plastered wall that stops short of the floor or dry-lining?

Hard plastered - some form of breeze block and then hard plaster on top. Onto a maybe-insulated concrete floor but judging by the rest of the build, the min BRs needed in 2001.

[Radian]

3 hours ago, Sparrowhawk said:

the min BRs needed in 2001.

There should be some insulation down there, the max U-Value for floors in 2001 was 0.51W/(m²K). Ours was built 1997 when the requirement was 1.2W/(m²K) yet the builder laid 50mm XPS over the block & beam. Wish it was PIR. And 100mm thicker.