Double (2Ply) EasiJoist joints...?

[WoodpeckerDentMan]

Currently on with installing EasiJoists on the first floor. The plan says the 2 PLy joists need joining together on site.  I'd prefer to glue and screw them together, but they have supplied these wacky little brackets. Anyone used these before on EasiJoist? I've got 2 x 2Ply joists that are supposed to be joined together and they've supplied these brackets. Not entirely happy using them as it will mean the top face is no longer level. Any alternatives anyone? I'm of a mind to glue them and strap them together until dry. Unfortunately, it's Sunday and LincFrame aren't working today!

[SteamyTea]

Can't really comment on your particular details, but structural engineers is much more than just ultimate strength.

While I prefer to use an adhesive, and sometimes the correct type of bolting, they are not always as obvious and intuitive as they seem.

There are so many different adhesives, and they all need the correct preparation, the manufacturer of the joists may have decided that it is safer to use custom designed fittings.

There is also failure mode to consider. A catastrophic failure at a lower energy level is much safer than at a higher level. The brackets may have been designed to fail early, while still leaving 2 joist intact.

Generally, as a rule, follow the manufacturers instructions.

Edited September 28 by SteamyTea

[WoodpeckerDentMan]

36 minutes ago, SteamyTea said:

Can't really comment on your particular details, but structural engineers is much more than just ultimate strength.

While I prefer to use an adhesive, and sometimes the correct type of bolting, they are not always as obvious and intuitive as they seem.

There are so many different adhesives, and they all need the correct preparation, the manufacturer of the joists may have decided that it is safer to use custom designed fittings.

There is also failure mode to consider. A catastrophic failure at a lower energy level is much safer than at a higher level. The brackets may have been designed to fail early, while still leaving 2 joist intact.

Generally, as a rule, follow the manufacturers instructions.

It's a fair point well made. I've gone for the brackets supplied as time is ticking. Not the easiest of things to install mind, but we got there in the end! 

Thanks for your input. 🙂

[WoodpeckerDentMan]

LincFrame got back to me this morning, and that IS how they're supposed to be joined together. Definitely not easy getting them brackets screwed up tight to the corners then inserting the second beam between the two sets of brackets, but using a thin wide bladed scraper to ease the edge of the timber into the brackets a little at a time got us where we needed to be. 

Having use of the steel ridge beam to hang a block and tackle off to lift them up made installation a lot easier. 

[WoodpeckerDentMan]

Thought I'd attached photos of the little brackets to the original post, but can't see them now.😕

 

Here they are in case anyone in future comes across them...

[ProDave]

Can you show a picture of a pair of joists fixed together with these brackets?  I am struggling to understand exactly what they do?

[WoodpeckerDentMan]

Yeah, sure. Basically, the face of the bracket facing the camera on that bottom pic with 2 screw holes goes into the side of the joist, then the two holes on the top get 2 more screws into the same joist. That leaves 4 holes (2 either side of where the bar-code sticker is) to go into the second joist, but as 2 of the screws go into the first joist on the side, you have to put those in, and all the brackets on both top and bottom edges, BEFORE you put the two joists together. They're only small skinny brackets, with 3.5x30 screws in them, but there's about 36 of them on each pair of joists!

The 2-Ply joists are specified for either side of the chimney and stairs that will come through from the existing house. A big chunky trimmer will next be hung between the two 2-Ply joists and then 5 more shorter joists hung off the trimmer. It's a lot of wood for a floor, but it's a huge span, so it is what it is.