On a timber frame house, should the window be attached to the frame, span the cavity, or hang off the brickwork?
Also, I need at least a "100mm reveal" for conservation purposes, but I'm getting different stories on what this means.
If the window is on the timber frame, should the bricks overlap the box holding the weights and should they therefore bridge the cavity?
Any help would be greatly appreciated.
In article , snipped-for-privacy@gmail.com writes
Traditionally mounted on the stonework with the outer face of the frame fixed to the inside face of the stone, the construction of the windows makes this just about the only way that it works. Normally the stone cill will be inset on the inside of the wall so that the weight of the window sits on that before fixing. In t'olden days there would be a 1/2" gap between window & stone filled with mortar & finished in mastic mortar but I fitted mine with the minimum gap I knew I could get a good wodge of frame sealant into, about 3mm.
At a guess I'd say the distance from the front face of the stone to the front face of the window frame but that is a guess.
Nah, but I expect the BCO will be expecting a firestop in the cavity. If you've not seen a made up sash & case window before it is a bit of a disappointment, when they say 'sash boxes' they don't actually come boxed it, you have front plate, back plate & the frame between and that's it. Things get a bit more obvious when you see them delivered.
There are actually people here that make these things for a living so I'm sure they will correct any misinformation, my info is based on local practice (Scotland) on big windows ~ 2.4x1.2m.
"reveal" means that part of the insides of a wall revealed when an opening is constructed. So a hole in a 9" brick wall has a 9" reveal etc. Your "100mm reveal" means that about a 100mm depth of masonry should show infront of the window i.e. a brick thickness if it's a brick wall. This is obviously impossible with a single brick wall such as you might have in a timber framed building, so the front lining of the window has to be flush with the external face of the wall - no reveals at all. In a 9" wall a sash would normally be put in an
100/150mm rebate on the inside so that only the edge of the front lining will show to the outside and the inside linings will be flush wth the inside wall - the join covered by an architrave. In a thicker wall there will also be reveals on the inside, often splayed. Sash windows are later than timber frame buildings so don't always fit easily not least because timber frame is often a composite of timber and other masonry, nd often not straight.You could have one side against timber and the other against the infill (brick etc) or other variations. Have a look at whats already there. Sashes are always fitted by sitting on a cill with spacers under each corner such as bits of slate or glass and folding wedges at the top. Old ones often really easy to remove - you just loosen the wedges at the top corners and the whole thing falls into the room. cheers JacobYou could go by the amount of space left over between the last rain drip groove in the cill. Wooden ones have to hang over the brickwork by a fair bit. Look to get some 30 mm give or take quarter of an inch on the reveal between the uprights of the window and the outer edge of the wall.
With a timber frame they may have supplied enough bits of mdf or whatever to form the cavity closers. These may be 1/2 or less. Get some decent stuff, 3/4 of an inch thick or so, as any draught in the cavity will cool the areas around your windows.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.