Finishing window reveal around brackets?

[BadgerBadger]

Rational windows are in, and have been fitted to internal block work with brackets.  But I seem to be a bit stuck on how to finish the internal reveals?

 

All my drawings just show insulation material around the brackets with plasterboard on top.   But any ideas how I actually achieve that?! Rest of the walls are wet plastered.

[Russell griffiths]

There’s a product called JACKOBOARD it’s an insulation board that can be plastered onto using the right primer. 
you can get it in multiple thicknesses, if you bought say 20 mm thick you cut it to size and put it in the reveal, give it a thump with your hand and the brackets will leave an imprint in the back side, cut out the imprint and the board will sit over the brackets. 
you need to talk to the plasterers about correct positioning, to line up with there finished skim. 
the board can be fixed on with rapid set tile adhesive or a good quality no nails type stuff. 
 

just one way to do it. 

[crispy_wafer]

Would an Alternative be, J profile fixed to the frame, and dabs to blockwork to clear the fixings.  Currently looking at methods myself as I don't have rigid closers, the cavity is covered and sealed with 200mm window tape and soudal paint.

 

Side note, I'd have a go at sealing up and taping them closers as best you can.

[Oz07]

Youve only got a certain thickness to work with its not like you can fit 50mm insulation between brackets and plasterboard. Is the thermal performance of such a small amount of insulation really going to make much of a difference in this situation? Id be inclined to just fit plasterboard up that reveal with a full backing / bed of that fm330 air tight foam stuff hopefully then seal up those cavity closers

[Oz07]

How far are your frames overhanging the cavity out of interest? Im always looking how people do this detail and finish it. Can door frames be fixed just on brackets too or do you need side fixings into substrate?

[Chanmenie]

14 minutes ago, Oz07 said:

How far are your frames overhanging the cavity out of interest? Im always looking how people do this detail and finish it. Can door frames be fixed just on brackets too or do you need side fixings into substrate?

You can fit door frames with brackets same as those window pictures 

[Oz07]

The weight of the leafs ok on brackets like that? Do the jambs not bend?

[Russell griffiths]

4 minutes ago, Oz07 said:

The weight of the leafs ok on brackets like that? Do the jambs not bend?

I have a couple of heavy doors

i fitted a rip of 12mm ply the same thickness of the frame directly to the frame, as a packer, I then cut a rip of 18mm ply the same width of the frame and the internal reveal. 
I used the 18mm ply as a full length bracket, you can fix anywhere you need, lots of fixings at hinge areas. 
the 12mm packing ply is the exact thickness of plasterboard, so you can plasterboard straight on to the 18mm covering the fixings and it will sit perfectly gapped all around the frame. 

[Oz07]

So you had your frames made 18mm smaller all around or made internal openings 18mm bigger? Or am i misunderstanding 

[Chanmenie]

1 minute ago, Oz07 said:

The weight of the leafs ok on brackets like that? Do the jambs not bend?

The weight is on the floor.

My build is ICF so I inserted 4 x2 timber into the EPS bolted to the concrete core then used brackets to fix the doors 

 

[ProDave]

I used offcuts of 20mm thick wood fibre board notched round the fixing brackets, then my air tight membrane taped to the window, then plasterboard.

 

Cut the ends of the wedges off close to the window so they are not an additional obstacle.

[Russell griffiths]

9 minutes ago, Oz07 said:

So you had your frames made 18mm smaller all around or made internal openings 18mm bigger? Or am i misunderstanding 

I don’t have any brickwork to marry up with windows or doors, just icf. So the rough opening was 30mm larger than the door in the first place. 
 

[Super_Paulie]

just had the same situation this week. I was too impatient to wait for a delivery of insulated tile backer and my car cant carry sheet material (2 seater) so i just did what Oz suggested above. Foamed and taped the cavity closer then a full bed of foam and 12.5mm board to give me the clearance over the brackets. My thoughts that the full bed of foam will provide some thermal break or insulation may or may not be correct.

I left the reveals long and then used insulation board on the walls to bang up to them then cut them down to flush.

For what its worth i think the cavity closers are sh*te, or at least the way my builder installed them maybe is. Always "gappy" like your image, which requires me to foam and tape them all down and brace them until they go somewhere near straight.

Edited September 12 by Super_Paulie

[Oz07]

The ones you build in as you go are a lot better. More rigid plastic. Only thing is they aren't always as well insulated as they should be

[Super_Paulie]

2 minutes ago, Oz07 said:

The ones you build in as you go are a lot better. More rigid plastic. Only thing is they aren't always as well insulated as they should be

yeah, bent flimsy plastic and an inch of polystyrene doesnt instill confidence.

[BadgerBadger]

Thanks all - so general consensus is there's no set solution and I need to work something out 👍

 

Variation in the brickwork reveals mean the gap to build-up is different on every window, need to get airtightness sorted, and aiming for bullnose plaster corners too 🫣

[BadgerBadger]

On 12/09/2024 at 08:31, Oz07 said:

How far are your frames overhanging the cavity out of interest? Im always looking how people do this detail and finish it. Can door frames be fixed just on brackets too or do you need side fixings into substrate?

 

Quite a bit, there's about 30-40mm of frame over the outer leaf and the rest is in the cavity supported by the brackets fixed to inner leaf.

[Dave Jones]

cut all the foam off flush, air tightness tape frame to the INSIDE block. Then 25mm insulated plasterboard (not really needed but cheap) over the top and skim. Remember to fit window boards first.