Joist Notching for Sliding Door Assembly

[JabeccaT33]

Hi All, hoping someone can help with some advice.
I’m in the process of building a deck off the dining room of a 2-storey house.
I have all the engineering for the build, but one detail is not as I would like it.
There is a triple sliding door assemble being fitted to the wall of the dining room which will exit onto the new deck and the issue I have is that the design sets the timber reveal of the sliding doors directly on top of the floor joists. I’m not happy with this because of the 50mm trip hazard it creates. To bring the aluminium door frame level with the floorboards, so there is no trip hazard, requires a 165mm L x 50mm D cutout into the top of the floor joist. I’m concerned that this will weaken the joist to much considering there is already a 75mm x 25mm cutout on the underside of the joists where it sits on the top plate of the wall below. The joists are Queensland Hardwood and measure 145mm x 50mm.
I have included attachments to hopefully clarify the situation.
Any suggestions how to address this issue would be greatly appreciated.

 

[phamENG]

Bad idea for two reasons - one, you're weakening the joist too much. I'm not in Australia, but here in the US that cut would violate the building code. Two: in my neck of the woods, the sills of doors like that are almost always proud of the floor. Because we don't want water in the house. Perhaps you live in an arid or desert climate and that's not an issue, but it is here.

You say you have engineering done - then go back to the engineer and share your concerns. The engineer should be able to explain to you why you can't do it, or make the changes you want.

 

[jayrod12]

Agreed with Pham. That notch looks nasty.

That being said, there may be some options there depending on a few things.

One option, install it flush with the top of joists but set down into the sheathing. That may only get it 13mm below top of floor. Then you could look at having a slight ramp/slope the remainder of the way.

A second option, provide a new bearing detail fastened to the face of the wall below that supports the joists beyond the notch. The potential issue here is making that look like something normal when viewed from below.

How wide is the wall framing below the joists?

 

[JabeccaT33]

Hi phamENG, that cutout would also be an unacceptable in Australia without some form of corrective measures to address the problem. That is the reason for my post, to get different ideas from the wider engineering community. The water issue is not a concern as the doorway is on the second floor and opens onto the deck which is 25mm below the existing floor. Unfortunately the engineering service that I used has closed their business and retired.

Hi jayrod12, your second option was an idea I had already considered. I have attached images from a 3d model showing the concept. The intention is to fabricate a steel bracket using 150 x 90 x 8 Unequal Angle and 65 x 6 Flat Bar. The bracket would be bolted to the top plate of the wall with two M10 bolts, grade 8.8 and secured to the joist using six Hex Head Type 17 wood screw.

If anyone has any concerns with this corrective measure, please let me know.