Loft floor strength

[Lewism3]

I'm doing a presentation on loft conversions, yippee!!!

I realise the loft floor requires strengthening, but how is that carried out? What are the differences with traditional purlin/rafter roofs and trussed roofs regarding floor strength?

Any help is greatly appreciated.

Martin

 

[masona]

I realise the loft floor requires strengthening, but how is that carried out?

Using a calculation chart of span, length, weight etc a bigger joists from wallplate to wallplate & bearing walls or RSJ method.

What are the differences with traditional purlin/rafter roofs and trussed roofs regarding floor strength?

Traditional roof is stronger and easy to do loft conversion, the gang nail roof trusses is clevely design to use less timber but difficult to do loft conversion but not impossible, the gang nail trusses are a big problem for those who want loft floor storage space even more so the new home build now have 10" insulation!

 

[Lewism3]

Thanks for the info.

Do you remove the ceiling joists and replace them with stronger alternatives, or simply add support to the existing ceiling joists?


Martin

 

[masona]

You just put bigger joists next to the ex-ceiling joists

 

[Lewism3]

Thanks Masona

Much appreciated.

Martin