# Forum Home Renovation Sub Flooring  Floor load width?

## pete74

Hi there,
I have been checking span tables for replacing parts of a rotten deck. Can I confirm that the "floor load width" is half the distance between bearers (bearer spacing/2)?  
Also if someone can confirm that 2 x 240x45 F27 kiln dried hardwood for a single span of 3800mm is suitable? No roof load. 
Thanks

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## 2x4

To calculate your bearer size accurately FLW needs to be taken into account as well as the live load of thr floor. 
But a single span of 3800 with a FLW of 2400 and joist spacings at 450, no roof loads, you could get away with 1 x 240x45 F27 kiln dried hardwood. Depending on the floor live load you will need 2 x 240x45  
.

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## cherub65

> Also if someone can confirm that 2 x 240x45 F27 kiln dried hardwood for a single span of 3800mm is suitable? No roof load.
>  Thanks

   Could use 2 x 240 x 35 F27 with a FLW up to 3.3m

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## bpj1968

FLW is half the distance between the bearers on EACH side, i.e each bearer supports half the weight
FLW = Bearer spacing/2 * 2.......... or.... bearer spacing on common applications 
Dividing by 2 comes into play where the bearer spacing is different on either side, or on the end bearer 
Have a look at the Timber Solutions Program You can plug in all your different variables and it will wolrk it out for you. 
It came up that at 3600 span 
2 x 240 x 35 F27 with a FLW up to 3.6m
2 x 240 x 45 F27 with a FLW up to 4.9m 
Although the load would be at 100% which is not a good idea 
I found this pic which shows it a bit better, except the green FLW is a bit long and the 3rd Across bearer B, should in fact be bearer c = (Y+Z)/2

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