Unvented in a loft

[townfanjon]

Guys , anybody know where I would get the following info ( no luck with building control asked them a while ago )
customer wants a unvented in a loft , I will not just put marine ply down and plonk it on that , from a job years ago I am pretty sure you cross the roof trusses with new joists covering at least 4 trusses and then cover in ply, but I am struggling to find the right info.

Thank you in advance

 

[ShaunCorbs]

Guys , anybody know where I would get the following info ( no luck with building control asked them a while ago )
customer wants a unvented in a loft , I will not just put marine ply down and plonk it on that , from a job years ago I am pretty sure you cross the roof trusses with new joists covering at least 4 trusses and then cover in ply, but I am struggling to find the right info.

Thank you in advance

yea upto 300 litres 4 trusses like below pic

 

[townfanjon]

Cheers Shaun, perhaps my memory is not as bad as i thought lol.
This one will go into the middle of the loft and theres probably a total span of 9/10 meters maybe longer I couldnt get all the way over, could go back monday and measure the building width from outside !!
So not sure if thats any bearing on the calcs on the stresses placed on the truss .

 

[ShaunCorbs]

Cheers Shaun, perhaps my memory is not as bad as i thought lol.
This one will go into the middle of the loft and theres probably a total span of 9/10 meters maybe longer I couldnt get all the way over, could go back monday and measure the building width from outside !!
So not sure if thats any bearing on the calcs on the stresses placed on the truss .

even better if there a supporting wall in the middle if it

 

[joni os]

The bottom cord of a truss is not designed to take tank loadings. To overcome this lower bearers should be positioned close to node points, spanning 4 trusses. This is then counter battened by two joists positioned so as to sit on bearers midpoint between outer trusses, thus ensuring load is distributed to all 4 trusses. With trusses at 600 c/c this means joists would be at 1200 c/c. (300 + 600+300). Platform for tank is then constructed off these joists.
REF: Trussed Rafter Association Technical Handbook.

 

[buckley plumb]

I though it was bearers one way then more pn top the other way.

 

[Worcester]

So we go to all the trouble of working out the support because we are a plumber and not a structural engineer, and then...

I though G3 regs required maximum of 600mm from the temperature relief valve to the tundish... (3.54)

 

[ShaunCorbs]

So we go to all the trouble of working out the support because we are a plumber and not a structural engineer, and then...

I though G3 regs required maximum of 600mm from the temperature relief valve to the tundish... (3.54)

for the 3rd time not my pic and it was just to show the support but theres a few problems as you have stated one

 

[Worcester]

Hi Shaun, sorry didn't realise

In which case.... no, I won't list them

 

[ShaunCorbs]

Hi Shaun, sorry didn't realise

In which case.... no, I won't list them

np least he can use a bender and not all fittings