Floor lateral restraints at intervals <= 2m. Am I interpretting this correctly?

[Digmixfill]

It's time for floor joists in one room of my conversion. I've still to decide if i'm going with webbed joists or solid timber and whilst looking through information for webbed joists I started to confuse myself.

 

Webbed joists for spans that we have will require a strongback across the room. This will have a restraint strap holding it to the blockwork.

Timber joists will just have strutting across the room with no requirement for straps at the strutting point.

 

For the purpose of my puzzlement assume a room 3.7m square. This is over the 3m requirement for lateral restraint straps.

Part A 2C35 says "Walls should be strapped to floors above ground level, at intervals not exceeding 2m and as shown in Diagram 15."

 

 

With the timber joists I had thought that I needed to put 2 straps at 1.23m spacings.

With webbed joists having a restraint strap at the centre of the span the distance between the strap and each end of the room is 1.85m. Does this mean that no further straps are required for the webbed joists?

 

 

[markc]

Hi, can you clarify what you are wanting? Strongbacks assist the floor`s stability and rigidity while strapping is there to restrain the walls, not the floors.

You can never have enough or too much strapping, always err on the side of caution - nothing worse than someone pushing a heavy sofa against a wall and the wall bowing out and staying there.

[Digmixfill]

From a webbed joist installation document

 

 

This would give a restraint strap at the centre of the span.

[Mr Punter]

Yes, if the wall is only 3.7 just one strap in the middle.

 

Did you tie the blockwork into the stone outer wall?

 

Can you post some more pictures of progress?

[Digmixfill]

Yes, the internal blockwork is tied to the outer 9 inch brickwork with resin bonded ties.

 

5 minutes ago, Mr Punter said:

Can you post some more pictures of progress?

 

You just want to see my naff blockwork don't you

 

I'll go try grab a couple of decent pictures.

[Mr Punter]

1 minute ago, Digmixfill said:

You just want to see my naff blockwork don't you

 

I was interested to see how it worked with the wonky walls.  Are you doing polybead insulation or did you insulate as you built?

[Digmixfill]

Just now, Mr Punter said:

 

I was interested to see how it worked with the wonky walls.  Are you doing polybead insulation or did you insulate as you built?

The straight internal wall accentuates the wonk when looking at a doorway or window reveal, but that won't be as obvious when plaster boarded. Other than needing lots of different sized ties it's turning out ok so far.

 

I'm fitting 90mm PUR as I go and might fill the remainder with beads or something else later.

[Digmixfill]

Pictures ?

 

Row where hangers will go.

 

Other side where i'm going to bolt ledger plates either side of the 9 inch internal wall.

 

I've tried two ways of closing the cavity. Cutting the PUR boards flush with the edge and filling the remainder like this.

 

And cutting boards to make a fitted piece face on. This is the better method I think.

 

 

 

Hopefully you can see that the cavity gets wider toward the top of the reveals in these pictures.

 

 

[Mr Punter]

It is looking really good!  Have you worked out where the windows are going - front- to back in the reveals?  I looks tricky with the outside walls leaning a bit.

 

Doing the blockwork off a small scaffold tower is quite a feat.  Maybe and extra change of underwear will be needed when it goes higher.  Will it bond at the corner after the next course or so?

[Digmixfill]

Thank you

I'm getting neater at blockwork but I'm still sloth like. I'm quite used to the scaffold boards over the wobbly towers - I've not fallen off or spilt any tea yet. Three towers in that room means I can walk the full wall. My plan is to drop the hangers on and bolt up the ledgers and fit the joists. Add the 3 courses of block over the hangers, and then move the towers up over the joists.

 

The corner is going to be a bit like tetris for two courses. The last corner block on the hanger row is bonded over the corner block. I have been trying to avoid coursing both walls and buggering up matching courses with the PUR board. Not sure if I've saved myself any hassle by doing this or not.

 

Our plans specify to fit the windows and doors a particular distance back from the face of the outer brickwork. I *think* it is 50mm, but I've not looked at that part of the plans for a while.