Ceiling / floor joists no noggins

[skhudy]

Double story extention, Ground floor room being refurbished, built 45 years ago. Pulled down ceiling and there are no noggins on the 8x2 joists (10 ft span)

Is it worth putting them in now?

The ceilings in the extension do have cracks, so I assume there has been some movement since it was built

Thanks!

 

[Deleted member 174758]

Noggins are in stud walls, strutting is in floors - the difference is that there are "rules" about what you need to do to get strutting to work. There are also different types if strutting - herringbone strutting is the most effective whilst solid strutting (what you incorrectly referred to as "noggins") are a cheaper, less effective solution. But more to the point, do you need them? Strutting is generally used on floors where the width of the floor exceeds 16 or so feet or the joist span exceeds about 16 feet. Your floor doesn't exceed those dimensions, so quite rightly it would never have been installed when the house was built. Does your floor have problems? If it's out of level you may want to sister the joists with something like 4 x 2 CLS to level the floor through. TBH on 10 ft joists I can't see you needing to strut because your floor shouldn't be so bouncy that it needs it (the main reason to install strutting is to make floors on long joists/in wide rooms more rigid). If you do insist on installing them the rule is that the strutting ideally needs to be the same depth as the existing joists (or at least 80% of the depth) and the same thickness, the rows of strutting need to be set at 1/3rds across the floor, and they must run in line, never staggered which will require angle nailing with something like 4in rounds at one end (nailing is preferable to using screws). TBH though 8 x 2s are more than man enough for the task - your cracks are probably just the result of natural settlement or possibly overactive teenagers

 

[skhudy]

Thanks, useful info! No real reason to put them in then. rooms being refurb'ed, just thought if they were needed now was the time to put them in whilst the ceiling was down