Cavity closers

[eandg]

Total novice question this I'm sure but I've just came across the requirement for cavity closers. Who's responsible for fitting these, window fitters and leaving in situ for brickies or brickies pre/post laying?

[Mr Punter]

Normally with bricklaying, but they are simple to fit.  Have a look at the reveal before the closers go in to make sure the insulation have been properly fitted.

[eandg]

43 minutes ago, Mr Punter said:

Normally with bricklaying, but they are simple to fit.  Have a look at the reveal before the closers go in to make sure the insulation have been properly fitted.

 

Thanks. Planning on some timber cladding which I'll be DIYing, just the same practice there? 

[Mr Punter]

33 minutes ago, eandg said:

Thanks. Planning on some timber cladding which I'll be DIYing, just the same practice there? 

 

If this is the cavity between the cladding and the structure this is often closed off with timber or rockwool fixed to the structure.  The idea is that if a fire takes hold in the cavity it will not find its way into the building via the window or vice versa, which is, I understand, what happened in Grenfell.

[eandg]

2 minutes ago, Mr Punter said:

 

If this is the cavity between the cladding and the structure this is often closed off with timber or rockwool fixed to the structure.  The idea is that if a fire takes hold in the cavity it will not find its way into the building via the window or vice versa, which is, I understand, what happened in Grenfell.

Thanks, so effectively just a treated timber baton round the window could act as a cavity closer? 

[Dudda]

30 minutes ago, eandg said:

Thanks, so effectively just a treated timber baton round the window could act as a cavity closer? 

Yes but you'd be better going with a rockwool batt or similar that would help with the thermal performance.

[Dave Jones]

buy them ready made, the brickies will thank you as they wont have to level up the sides of the windows. They are dirt cheap and are held in with straps built into the brick courses.

[Brickie]

3 hours ago, Dave Jones said:

buy them ready made, the brickies will thank you as they wont have to level up the sides of the windows. They are dirt cheap and are held in with straps built into the brick courses.

Not in a million years would I trust one of those formers to stay true & plumb as the wall goes up. 

[Adsibob]

So my builder somehow forgot to put cavity closers into the brick piers either side of a large gap where we are fitting sliding doors. The plan is to use an angle grinder to cut into the bricks to fit them. The scars from this operation will be concealed by the frame of the sliding door, which is almost 30cm thick, but I’m still wondering whether there is some less dramatic way of retrofitting the cavity closers. Any ideas?

[Russell griffiths]

10 hours ago, Adsibob said:

So my builder somehow forgot to put cavity closers into the brick piers either side of a large gap where we are fitting sliding doors. The plan is to use an angle grinder to cut into the bricks to fit them. The scars from this operation will be concealed by the frame of the sliding door, which is almost 30cm thick, but I’m still wondering whether there is some less dramatic way of retrofitting the cavity closers. Any ideas?

 

Not sure what you mean, the cavity should be open and the closer will just slot in, do you just have bits of face brick in the way from the face, or has he fully bricked it up. 

[Adsibob]

2 hours ago, Russell griffiths said:

 

Not sure what you mean, the cavity should be open and the closer will just slot in, do you just have bits of face brick in the way from the face, or has he fully bricked it up. 

He’s fully bricked it up. BCO said “where is the cavity closer” builder said “whoops”. But architect says thatwe are putting a double glazed thermally broken sliding door unit there, there is no need for a cavity closer. Not sure whether BCO is being OTT.

Edited April 18, 2021 by Adsibob

[Russell griffiths]

8 minutes ago, Adsibob said:

He’s fully bricked it up. BCO said “where is the cavity closer” builder said “whoops”.

Ok so hire a reciprocating saw for brickwork, it looks like a curved blade not a spinning disc, it moves up and down instead of spinning so doesn’t make the dust so you can see where you are cutting. 

[Dave Jones]

On 17/04/2021 at 19:37, Brickie said:

Not in a million years would I trust one of those formers to stay true & plumb as the wall goes up. 

 

obviously not used the  factory braced ones.

[Brickie]

Used them many times pal. 

[Johnny Jekyll]

Reading this thread. Can anyone recommend good quality cavity closers to use? Links would be great thanks.

Our new build is made up of 100mm medium block to 100mm full fill PIR insulation to 100mm medium block to render.

Many thanks.

[craig]

Bigblok by Cavalok 

[Oz07]

I see stepped ones on a new development near me which keeps the blockwork opening around 25mm wider each side. Windows fitted up to back of face brickwork which is unusual for volume developer. 

[Johnny Jekyll]

2 hours ago, craig said:

Bigblok by Cavalok 

 

These look great but it looks like they are only available for 125mm + cavities. My cavities are 100mm. Any other recommendations thanks? 

[eandg]

On 16/04/2021 at 12:28, Mr Punter said:

 

If this is the cavity between the cladding and the structure this is often closed off with timber or rockwool fixed to the structure.  The idea is that if a fire takes hold in the cavity it will not find its way into the building via the window or vice versa, which is, I understand, what happened in Grenfell.

https://www.ebay.co.uk/itm/203747003411?hash=item2f70448c13:g:poAAAOSwubths3dB&amdata=enc%3AAQAHAAAAoDWCqOGvn%2BWTQGIv9G0pi4S2vQXm23hLxU1R%2FTwrezqanSzKXaXx52VYDB4%2Bea7N0Ww5KpPoPVtL9EjhM%2BfbUDR0DaK8gy%2BvE%2FpT6uuB8B7HLBgW0S7c24hzL9C%2BjCMN7K3HAuhIZyu1vQ91tlTDRmaArAfdeL9USWggoy0N18w4cOXGyl9TEdiinfoU8ympHhqTVZ5VQwjP0STxLrp3vXM%3D|tkp%3ABk9SR7TZvI3DYQ

 

These are advertised as 65mm but for 50-60mm cavities. I have a 50mm cavity - would these be sound?

 

 

[Mr Punter]

8 hours ago, eandg said:

These are advertised as 65mm but for 50-60mm cavities. I have a 50mm cavity - would these be sound?

 

Yes, they should squeeze in and be nice and snug.

[eandg]

Is there any benefit in using the insulated cavity barriers at corners, floor levels etc compared to 2*2s wrapped in DPC? I can see the benefit fit windows but unclear if they add anything elsewhere. 

[Dave Jones]

On 19/04/2021 at 07:38, Brickie said:

Used them many times pal. 

probably the type of brikkie who thinks gauging buckets take too much time as well..

[Brickie]

1 hour ago, Dave Jones said:

probably the type of brikkie who thinks gauging buckets take too much time as well..

Less time than a spell check. 

[eandg]

I can't find any detail of cavity barriers at lintels, and I had a quick play about with a rockwool batt and a lintel and it doesn't look like there's the room to fit it in. Any thoughts?