Joist span in kitchen

[olidiy]

Hi guys

Ive moved into a 1960s semi detached property which has had some work done to it.

Recently i laid a new floor in my bedroom but i had a radiator moved so took up some floorboard at the same time. The kitchen is below my bedroom and it is 5.9m x 4.2m. The joists run the length from front to back at 5.9m. They are 195mm x 47mm and have been doubled up at 450mm centres. it also looks like they have put noggings in two places.

My question is, is this strong enough? Seems like a big span and i was a bit worried after my discovery

thanks in advance

oli

 

[freddiemercurystwin]

Have the joists been there since the 1969s? Are they sagging? Does the floor bounce much when you walk on it etc? If the answer is yes and not much then don't worry about it.

 

[olidiy]

Don't think so. The kitchen is about 3 years old from what the neighbours say it was all done then. The floor doesn't feel bouncy and there aren't any cracks in the ceiling of the kitchen. Thanks

 

[freddiemercurystwin]

Oh OK, didn't read your post correctly, are you sure they're spanning the full 5.9m then? Although do you mean there are double joists and if so are they bolted together or similar. Not ideal.

 

[olidiy]

Yes I stuck my head under and shined a torch and I'm pretty sure they go end to end with noggings. Yea they have been coach bolted together and nailed and nut and bolted in places aswell. Have I got cause for concern? Thanks again

 

[freddiemercurystwin]

I'm no engineer but I'd guess they're probably OK at least they've been bolted together, would have been more a worry if they'd not been.

By the book as singles they would have been something like 250x75's.

Fact is though standard timber span tables do not go up to this span as to get to these spans in standard single timber joists becomes uneconomical.

 

[olidiy]

Ok thanks. That explains why I couldn't find a span table that showed a distance of 6m then. I've not noticed any movement since I've been here. Puts my mind at rest cheers

 

[Static]

Assuming they are all doubled up then stress wise they would be ok, but you would get alot of bounce in the floor. Just avoid large parties in your bedroom!.. (unfortunately)