Bay window wall question



Is it normal to have no bricks under the bay window; just plasterboard? Under the bay window, the wall is extremely cold ( like every wall in the house), and I was just looking for gaps under the sill and pulled at a lumpy bit of silicone, the whole lump came away creating a big hole. I can see into the cavity and there are no bricks except of course for the outer leaf. I can see under the upvc window.
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So how do you think your bay window is being supported with all its weight? sure it must have bricks of some sort, what does it look like from the outside, is it bricks or rendered over bricks or blocks, it may be that it is made of solid bricks with an additional internal dry wall made of battens fixed to the solid wall and dry liner (plaster board) fitted over to stop cold coming in, the gap between the bricks and the dry liner should have been filled with glass wool insulation or similar, and a this may not have been constructed properly so possible you are seeing a damp wall with rising damp or condensation problem.

I have a same situation except my bay window does not have a dryliner and I am now getting very cold wall and it feels like it is wet, when I had that house empty for 10 years there was not a problem, now people live inside and the problem is man made, it is their habits like drying clothes on radiators and not ventilating the room to allow moisture to escape, and moisture will settle on the coldest spot and condense into droplets that makes the wall go wet and promote mould growth.
it is not unusual for bays, especially on the upper floors, to be a timber frame with tiles or boarding on the outside, and a plaster face on the inside. However you say that yours has a brick outer leaf.

Luckily, this not a difficult building job. Insulation can be put between the two skins, and a vapour barrier incorporated on the inner wall to prevent warm, damp air from the room getting into the gap and causing condensation.

It may be useful to pack mineral wool between the joists where they go into this cold space, to prevent cold air blowing under the floor.

I think you said on another thread that yours is a Victorian house, so most likely the walls are 9" brickwork with no cavity, so they are bound to be cold. It is possible to dryline the internal surfaces of the external walls to reduce heatloss, this will add several inches thickness. Rigid foam slabs of insulation are usual as they insulate better than the same thickness of mineral wool.
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Before I bought this house people kept telling me old houses are built properly, built to last, solid structures etc. etc. I have seen no evidence of this so far. All I have experienced is a cold draughty badly built dump. No bloody bricks in the wall! And that's normal?!
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Bricks missing? That's one rough neighbourhood.

Look at it this way, Shakespeare had a similar house. It's still standing too.
Before I bought this house people kept telling me old houses are built properly, built to last, solid structures etc. etc. I have seen no evidence of this so far. All I have experienced is a cold draughty badly built dump. No bloody bricks in the wall! And that's normal?!
LOL! did you purchase it in an Auction without conducting a proper survey?
My mate lives in a very big and posh Edwardian house. One room was always very cold, so he had the whole floor replaces with engineered oak faced boards ($$$) and the room was just as cold. He then hired in some chap who travelled 100 a day to take apart the wooden panelling under the bay window only to discover that the top layer of inner skin bricks was missing under the window frame!!. So a few dozen bricks and then the panelling was rebuilt. The only good thing about the job was the panelling engineer, you just can't tell its all be taken apart and rebuilt. That part of the job was brilliant. As a side note , the first Opo, removed an original bronze finished multi ribbed radiator and replaced it with a much smaller modern single panel one, sheer sacrilege.
It could be "typical" for the original carpenters to remove the top layer to get the window frame to fit, especially if they quickly panelled underneath it.
Frankly speaking I am a bit confused here, as you said the house was Edwardian build, so it most likely did not have a cavity wall, but a 9" solid wall. So if just a few bricks were missing from the inner layer at the top row, just under the window plinth, how would that cause the room to get so cold? May be the second guy also fitted some insulation behind the panelling so that the room became warmer.

Floor boards also compromise heat loss and feel cold compared to carpeted floors. It pays to install thicker insulation layer even under a solid wooden floor.
What age is the house? is the bay upstairs or downstairs? if it's a 60's house the bay could be just a hollow timber frame. People say that old houses are built well...........I've only ever lived in old houses (Edwardian and 30's) THEY ARE FLIPPIN COLD!!!!!!!! they are also built as fast as possible using any shortcut the builder could get away with. But, yes they are solid (the outside walls anyway) and the internal walls are normally solid brick or block which reduces noise and instills confidence that it's 'quality'. Usually they have bigger gardens than modern houses (which is why we buy them). But the foundations are shallow and the walls have to be built with a weak mix so that it can flex due to soil movement.

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