Suspended/stud ceiling

[TryAgain1]

I'm looking to add a stud ceiling to lower ceiling height from 2.7m to 2.4m.

3 of the edges are standard brick walls: for these edges I will use 150mm masonry screws to fix horizontal 3"x2" CLS timber (B) to the wall
1 of the edges is a steel RSJ: for this edge I will instead fix a 3"x2" timber to the ceiling very close by (to the RSJ) then have 3"x2" vertical drop down (from ceiling timber).

See diagram I have attached.

Any thoughts as to if this is right?
Advice please

 

[DAZB]

The usual way to do it would be to chock 3 x 2 or 4 x 2 timbers vertically into the web of the RSJ so they are a tight fit and sit flush with the face of the steel. That way you don't need to hang timbers from the ceiling as your 3 x 2 ceiling frame can fix to the chocks in the RSJ.

 

[TryAgain1]

The usuall way to do it would be to chock vertical 3 x 2 or 4 x 2 timbers vertically into the web of the RSJ so they are a tight fit and sit flush with the face of the steel. That way you don't need to hang timbers from the ceiling as your 3 x 2 ceiling frame can fix to the chocks in the RSJ.

True but I don't want to drill into the RSJ. Is my method ok?

 

[DAZB]

You don't drill into the RSJ, you wedge chocks into the web stood upright and then fix to those. Bit like this post here....

Noggings in RSJ

Can I just wedge some noggins into the flange of an rsj which is to be clad in timber? I understand to gripfill the bottom timber to the steel.

www.diynot.com

 

[TryAgain1]

You don't drill into the RSJ, you wedge chocks into the web stood upright and then fix to those. Bit like this post here....

Noggings in RSJ

Can I just wedge some noggins into the flange of an rsj which is to be clad in timber? I understand to gripfill the bottom timber to the steel.

www.diynot.com

Is wedged 3x2" CLS timber strong enough to hold a piece of a subtimber frame? Ceiling drop downs use more wood but are mechanically fixed. I did use this wedge chock method in steel RSJs but only to hold plasterboard around the RSJ.

 

[DAZB]

Yes because it cannot physically drop downwards as it is in the web of the RSJ, nor can it pull out as the studwork frame of the ceiling fills from wall to wall. You could drill, countersink and screw through the RSJ below each upright if you wish but really not needed.

 

[TryAgain1]

Yes because it cannot physically drop downwards as it is in the web of the RSJ, nor can it pull out as the studwork frame of the ceiling fills from wall to wall. You could drill, countersink and screw through the RSJ below each upright if you wish but really not needed.

So to double up I could screw the ceiling drop down to RSJ chokes (wood wedge) and screw the ceiling drop down to horizontal pieces of wood? This way it strengthens the frame

 

[DAZB]

Yes that would be strong enough. Make sure you have supports in the centre areas of the ceiling depending on the span you are covering.

 

[TryAgain1]

Yes that would be strong enough. Make sure you have supports in the centre areas of the ceiling depending on the span you are covering.

Good point. For a 3x2" spanning across, for a stud ceiling, what's the maximum unsupported length? I would need a ceiling drop down at set points

 

[DAZB]

For 3 x 2 timbers you are looking at a support somewhere between every 1.23m to 1.14m apart dependant on spacing and load so if you went with a fixed support every 900mm you would be well within the tolerances.

 

[stevie888]

Did you post the same question on the Screwfix forum convinced that the world would end if you drilled even a small hole in a steel?

 

[noseall]

I'm looking to add a stud ceiling to lower ceiling height from 2.7m to 2.4m.

3 of the edges are standard brick walls: for these edges I will use 150mm masonry screws to fix horizontal 3"x2" CLS timber (B) to the wall
1 of the edges is a steel RSJ: for this edge I will instead fix a 3"x2" timber to the ceiling very close by (to the RSJ) then have 3"x2" vertical drop down (from ceiling timber).

See diagram I have attached.

Any thoughts as to if this is right?
Advice please

150mm screws will be 50mm too long.
Use 100mm 6's with brown plugs and 7mm masonry bit.

 

[TryAgain1]

150mm screws will be 50mm too long.
Use 100mm 6's with brown plugs and 7mm masonry bit.

100mm 6s aren't structural screws. I thought only masonry or structural (coach) screws were acceptable for screwing 3x2 timber to brick?

 

[noseall]

100mm 6s aren't structural screws. I thought only masonry or structural (coach) screws were acceptable for screwing 3x2 timber to brick?

100mm 6's will hold half your house up.

 

[TryAgain1]

100mm 6's will hold half your house up.

100mm timberlock screws (like this https://www.screwfix.com/p/fastenma...ral-timber-screws-6-3mm-x-100mm-50-pack/56926) or 100mm wood screws (like this https://www.screwfix.com/p/turbo-tx...tipurpose-screws-6mm-x-100mm-100-pack/586vv)?