upcoming extension advice

[mattu27]

Thanks woody, same scenario as always. I can't get hold of the structural engineer despite emailing him yesterday and leaving him voicemails on his phone.

Another question, as the footings are filling up with water when we have rain, if we get a dry day and they are a little damp could the builders add some accelerator or waterproofer into the first few courses of blocks to get them past the dpc? It's literally one and a half blocks a course. The weather still looks rubbish and if they can get a window of good weather to get the blocks laid and set before the rains come again I'd like to go for it. Thoughts?

 

[^woody^]

You should not need and accelerator. The mortar will be going off within hours and there will only ever be relatively low amount of water in the trench for a short time, before it either drains or the soil is thrown back in, and this water wont harm the mortar or wall.

The 3:1 mix will be enough as this goes off faster anyway.

 

[mattu27]

Thanks again, hopefully the weather will ease off and we can get on with things. The footings seem to fill up very fast when it starts raining, think it's something to do with the tarp roof being draped down that side of the garage.

 

[mattu27]

We managed a dry day and got the start of the piers built up in 7n blocks, toothing in as they went up.

We plan to have the joists within the steelwork on a wall plate with joist hangers similar to https://www.diynot.com/diy/threads/joists-into-rsj-web-or-bolt-on-wooden-bearer.487660/

As the beam is a 203 X 133, if they fit a 47mm wide wallplate within the steel wouldn't the joist hanger clash with the steelwork unless the steel height is near to ideal floor height. Or should we go for a thicker wall plate to be clear of the steelwork?

Alternatively, I've seen another option where a timber plate is placed on top of the steel and the hangers are secured to this with the joist sitting in them.

Then there's the method that utilises both of these, timber between the web of the steel and on top.

Which one results in the least creaky floors?

As the piers aren't complete yet should the mid of the steel be at the same level as the middle of the joists?

Thanks, Matt

 

[mattu27]

Morning all, can anyone shed some light on my previous post? Getting the steels delivered today.

Thanks

 

[^woody^]

The timber in the web needs to be as deep as the flange or at least packed out to the edge of the beam. Normaly you would use speedy hangers which go up and over a timber plate and down the other side. But normally, the designer or engineer would specify this as part of the design.

Creaky floors is not related to any method, but relies on how good the job is done.

 

[mattu27]

Thanks again woody, sounds like a good plan.

I think the channel of the steel is 63mm so a length of 7" X 2" at 47mm with some 18mm cladding screwed to the back would get us somewhere near to ideal. And speedy hanger twist nailed on and over.

Just to clarify, would the timber plate atop the steel be needed then? There will be fibolite blocks on top of the steel so we could fit it in beforehand.

I've gave up with the structural engineer, doesn't answer calls and doesn't respond back.

Agreed about the floor.

Much appreciated.

 

[^woody^]

If you are blocking on top, you would use masonry hangers, and no timber plate on top

 

[mattu27]

Thanks again your advice has been invaluable.

Just got back to find the steels have been dropped off and are in the garage. The builders sorted them out as they had a mate at the supplier.....

There's no primer whatsoever on the steelwork, eventually it will be enclosed with plasterboard and within the floor but not in the immediate future. I was sure that this was standard practice nowadays to apply two coats of primer on steelwork. It will be resting on the exposed piers so some will always be on show in an unheated garage below a heated room.

Thoughts? Just Seems that whatever we don't define 10 times gets ignored.

Thanks

 

[mattu27]

If you are blocking on top, you would use masonry hangers, and no timber plate on top

Just had a look at these woody, they don't seem to have any face fix holes for the timber between the web of the steel. The only holes are on the top where they apparently bolt into the steel beam. Would these require drilled holes to secure into the steel?
Or could a traditional jiffy hanger nailed on the vertical and horizontal be better?

Guessing I'm missing something.

 

[^woody^]

Just had a look at these woody, they don't seem to have any face fix holes for the timber between the web of the steel. The only holes are on the top where they apparently bolt into the steel beam. Would these require drilled holes to secure into the steel?
Or could a traditional jiffy hanger nailed on the vertical and horizontal be better?

Guessing I'm missing something.

I dont understand any of that!

As you have a wall above the beam then masonry hangers can be used, and these just sit on the beam or above it in to the wall. These would need a timber in the web to allow the hangers to sit against it. The timber does not perform a structural function in this case, but would still need a few bolts through in to the web just to secure it.

Alternatively, you can use heavy duty timber hangers (not speedy straps) and these will screw and coach screw into a timber in the web, and in this case the timber does perform a a structural function so would need more bolts to secure it.

As for painting/priming, its good practice for have this done and good suppliers will do it, but it’s not strictly essential for an internal beam.

 

[Notch7]

Just had a look at these woody, they don't seem to have any face fix holes for the timber between the web of the steel. The only holes are on the top where they apparently bolt into the steel beam. Would these require drilled holes to secure into the steel?
Or could a traditional jiffy hanger nailed on the vertical and horizontal be better?

Guessing I'm missing something.

Get yourself a can of red oxide and paint it.......it could rust through in 100 years

 

[mattu27]

Get yourself a can of red oxide and paint it.......it could rust through in 100 years

It's more the point that both the structural calcs and building control have requested two coats of red oxide primer on all steelwork, but thanks for your input.

 

[Notch7]

It's more the point that both the structural calcs and building control have requested two coats of red oxide primer on all steelwork, but thanks for your input.

Yes I was only joking, it is best for steels to be painted in red oxide, it is certainly best practice........ the structural engineer and building control will put that on their drawing by defaut.

Internally there is a chance of condensation and damp causing a bit surface rust.

 

[mattu27]

Thanks Woody,

I've included a photo to show what I saw.

Hopefully it clears it up. I believe that the builders are planning to install the joists and floor immediately after the steels are in place so that they can start the first floor brickwork.

I noticed that the masonry hangers say to either top fix by using a hilti nail gun or to have a minimum of 670mm of fully cured masonry above them before they will accept any loading. That was the main reason for the worrying about securing them down. Is this the case?

Thanks