How do I join bits of wood together?

[The-bodger]

I need to put 4 more battens (up to 7inches deep) across my loft to support the new floor. The battens will be connected to the walls at both ends. But I can't get a 5.5 meter length of wood in my loft. The longest that will fit is 3.6 meter, which will then have to be joined when already in position to another bit of about 2 meters.
I have joists of 4x1.5 inches with 3 cross battens/binders at right angles holding the joists of the same size. I intend to raise the height of these cross battens by 3 inches to get a base for a floor (over the installed loft insulation of 270 mm glass fibre.)

1st idea
Glue two wooden plates to hold the union together like a sandwich? The two wooden plates must be strong enough to support the join. 7inch deep x1" by about 28" ( timber plates that are 4 times longer than that width). Glue all the surfaces together before drilling holes in the construction and either screw or coach?

Have you got any other ideas?

This is not a full loft conversion but I do need the storage space the loft floor will give me.

How would you suggest it should be done if I later want a loft conversion?

Many thanks
Anthony

 

[big-all]

heeelllooo The-bodger and welcome
place 2 side by side and where they overlap
just put 4 of these and some 10 or 12mmbolts through
http://www.screwfix.com/prods/99094/Building/Builders-Metalwork/Timber-Connector-50mm-x-M12

 

[The-bodger]

Hi
OK You say (place 2 side by side and where they overlap
just put 4 of these and some 10 or 12mmbolts through) You mean two 3.6meter lengths and bolt together to make a 5.5m length
yes that would do it. but how much needs to overhang?
I mean would using two 3m lenghts joined be as strong?

Anthony

 

[big-all]

if your trying to add strength then 2x3.3m would be the minimum i would go for then its not going to bend any less than a solid joist
500 puts to much leverage over a long span

or 3.6 +3m