Bolting joists together

[paulwf]

I am replacing the roof on my garage, as the current construction is inadequate.

The current joists are 38x220 at 600mm centres for a 6m span.

I need 75x220 joists at 400mm centres.

Therefore I'd like to reuse the 10 joists I have by bolting them together to give 5 of the correct size.

How often should I bolt them for this use?

Thanks
Paul

 

[freddiemercurystwin]

http://www.nhbc.co.uk/NHBCPublications/LiteratureLibrary/Technical/filedownload,21418,en.pdf page 5 probably

 

[paulwf]

Perfect thanks! That is a useful document.

Cheers
Paul

 

[garyo]

Removed - wrong section I think!