Packing above RSJ?

[higgster]

Hi guys,

I have just installed a 3.5m RSJ to part of the frontbof my house. I am getting different opinions on packing it out. Some say use slate then pack with a dry mix cement. Others say don't use slate as it can give pressure points. Others say use a non during grout. Please advise the best way. There is about a 30-40mm gap to pack out.
Is it ok to use a 3:1 sharp sand cement mix??

Your help as always is appreciated.

Non of my local diy merchants stock non shrink grout!!!

 

[Alastairreid]

Assuming you have used appropriate padstones slates would be the preferred option.

 

[jeds]

Pack with 3:1 semi dry mix using sharp gritty sand. If some of the spaces get a bit large you could also hammer slate into the semi dry mix. Semi dry means it should hold in a ball when you squeeze a handful in your fist. If water squeezes out it's too wet. Pack it in well with a piece of 35x100mm square ended timber.

Make sure the beam is fully loaded before you pack. Best way to do that is drive home folding wedges at 500c/c along the beam and pack between. When cured take out the wedges and pack the gaps.

 

[higgster]

Thanks for the reply,

when you say fully loaded, do you mean, put in wedges, remove the acro's/needles, and then pack? The RSJ is 203x203x46, I didn't think it would move when loaded as it seems huge!

 

[jeds]

Yes. The beam should be loaded onto wedges and the acrows released before you pack. If you pack and then release the beam (and packing) will deflect - maybe only slightly but any deflection might cause cracking.

 

[noseall]

The best way (if possible) is to offer the beam up to the masonry with a bed of mortar on the lintel so that it squeezes up to the bricks.

Wetting the bricks helps too.

 

[^woody^]

Yes. The beam should be loaded onto wedges and the acrows released before you pack. If you pack and then release the beam (and packing) will deflect - maybe only slightly but any deflection might cause cracking.

I don't understand that

You can't release the props before packing or the wall will drop!

 

[geraint]

Yes. The beam should be loaded onto wedges and the acrows released before you pack. If you pack and then release the beam (and packing) will deflect - maybe only slightly but any deflection might cause cracking.

think somebody is slightely mistaken there... But... as a genuine member of the forum...

Believe him and start your own website...

HOW DID MY HOUSE MOVE DOWNWARDS...

 

[higgster]

Thanks for the advice guys, I got it all packed out yesterday using slate and a semi dry 3:1 mortar mix. Will remove the props / needles tomorrow and fingers crossed any movement will be minimal. The internal Wall above is old thermalites so kind of expecting some cracking as they Always seem to crack elsewhere!

Now I need to make the call to the building inspector!

Thanks again

Matt

 

[jeds]

The best way (if possible) is to offer the beam up to the masonry with a bed of mortar on the lintel so that it squeezes up to the bricks.

Wetting the bricks helps too.

Agree with that. Of course it's not always possible. A good idea to make the bed slightly thicker in the middle to take up the deflection.

 

[geraint]

The best way (if possible) is to offer the beam up to the masonry with a bed of mortar on the lintel so that it squeezes up to the bricks.

Wetting the bricks helps too.

Agree with that. Of course it's not always possible. A good idea to make the bed slightly thicker in the middle to take up the deflection.

What absolute and utter rubbish...

 

[geraint]

The best way (if possible) is to offer the beam up to the masonry with a bed of mortar on the lintel so that it squeezes up to the bricks.

Wetting the bricks helps too.

Agree with that. Of course it's not always possible. A good idea to make the bed slightly thicker in the middle to take up the deflection.

So what do you recommend when the beam deflects....

maybe a cream tea